ABSTRACTS - euchems2014.org...molecules that could further streamline syntheses. The first step is...

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European Chemistry Congress - 5th EuCheMS August 31 - September 4, 2014 / Turkey

PL-01-01

The Elongation Cycle of Translation

V. RamakrishnanMRC Laboratory of Molecular Biology

Cambridge, United Kingdom

Following the determination of the atomic structures of ribosomal subunits in 2000, work has focussed on determination of the structures of ribosomes in different functional states along the translational pathway. Of particular interest is the elongation cycle, during which amino acids are added to a growing polypeptide chain as directed by the code on mRNA. This process involves two GTPase elongation factors, EF-Tu and EF-G, and involves three major steps: 1. Decoding, which is the accurate selection of tRNA that is cognate to the codon on mRNA. 2. Peptidyl transfer during which a peptide bond is formed between the new amino acid and the growing polypeptide chain, and 3. Translocation, in which the mRNAs and tRNAs move with respect to the ribosome. There are also exceptions which allow the ribosome to deal with starvation or stress. I shall summarize some of the work done in my laboratory during the past decade on this aspect of translation.

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PL-02-01

The Role of Ligands and Additives in Metal Nanocrystal Growth

Luis M. Liz-Marzán

Bionanoplasmonics Laboratory, CIC biomaGUNE, Paseo de Miramón 182, 20009 Donostia – San Sebastián, Spain Ikerbasque, Basque Foundation for Science, 48011 Bilbao, Spain

Email: [email protected]

Seed-mediated growth is the most popular methodology to control the size and shape of colloidal metal nanoparticles. The final nanocrystal shape will be defined by the crystalline structure of the initial seed as well as by the presence of ligands and capping agents that would help to stabilize certain crystallographic facets. This talk will focus on recent progress on the understanding of the role of surfactants, counter-ions and other additives during the seeded growth of gold nanorods [1-3], as well as the morphological changes derived from using such nanorods as seeds for overgrowth, either with additional gold [4,5] or with silver [6] (see Figure 1). Under different growth conditions, the morphological changes and corresponding optical effects can be drastically different, which may provide important hints related to the growth mechanism of the nanoparticles.

Figure 1. Examples of morphologies obtained by seeded growth on gold nanorods.

Acknowledgements. Funding from the European Research Council is acknowledged (ERC Advanced Grant # 267867, PLASMAQUO)

[1] L. Scarabelli, M. Grzelczak, L.M. Liz-Marzán Liz-Marzán, Chem. Mater. 2013, 25, 4232 [2] S.E. Lohse, N.D. Burrows, L. Scarabelli, L.M. Liz-Marzán, C.J. Murphy, Chem. Mater. 2014, 26, 34 [3] N. Almora-Barrios, G. Novell-Leruth, P. Whiting, L.M. Liz-Marzán, N. López, Nano Lett., in press [4] E. Carbó-Argibay, B. Rodríguez-González, J. Pacifico, I. Pastoriza-Santos, J. Pérez-Juste, L.M. Liz-

Marzán, Angew. Chem. Int. Ed. 2007, 46, 8983 [5] M. Grzelczak, A, Sánchez-Iglesias, B. Rodríguez-González, R. Álvarez-Puebla, J. Pérez-Juste,

L.M. Liz-Marzán, Adv. Funct. Mater. 2008, 18, 3780 [6] S. Gómez-Graña et al., J. Phys. Chem. Lett. 2013, 4, 2209-2216

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PL-04-01

Synergies between chemistry and nanotechnology

Maurizio Prato

Dipartimento di Scienze Chimiche e Farmaceutiche. Università degli Studi di Trieste. Piazzale Europa 1, 34127 Trieste, Italy

Nanometer-scale structures represent a novel and intriguing field, where scientists and engineers manipulate materials at the atomic and molecular level to produce innovative materials for making composites and for electronic, sensing, and biomedical applications. Carbon nanomaterials, such as carbon nanotubes and graphene, constitute a relatively young class of materials exhibiting exceptional mechanical and electronic properties, and are also promising candidates for gas storage and drug delivery.

Processing of these novel building blocks is severely limited by a number of inherent problems: purification from a variety of impurities, difficult manipulation and low solubility in standard solvents are only some of these problems. For these reasons, several strategies have been devised to make carbon nanostructures “easier” materials. In particular, chemistry plays a fundamental role, since it leads to functionalized carbon nanostructures, which are much more easily processible and offer the possibility of introducing the desired functions, useful for practical applications.

During this talk, we will show the role that Chemistry can play in nanotechnological applications. In particular, we will discuss how glassy surfaces, covered with carbon nanotubes are ideal substrates for neuronal growth. Nanotubes are compatible with neurons, but especially they play a very interesting role in interneuron communication, opening possibilities towards applications in spinal cord repair therapy.

In addition, in combination with catalysts of different nature, carbon nanotube modified surfaces can serve for many scopes. Experiments aiming at the splitting of water to give oxygen, and therefore, molecular hydrogen, ideal for clean energy generation, will be described.

References

(1) G. Cellot, M. Prato, L. Ballerini, et al. Nature Nanotechnology, 2009, 4, 126.

(2) Toma, F. M.; Paolucci, F.; Prato, M.; Bonchio, M. et al. Nature Chemistry 2010, 2, 826.

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PL-05-01

Water-Food-Energy Nexus: Impact on Water Quantity and Quality

Alexander J.B. Zehnder

Alberta Innovates – Energy and Environment Solutions, Alberta Canada, Nanyang Technological University, Singapore, and TripleZ Ltd. Switzerland.

One percent or less of the Earth’s water is usable for humans, the rest is in the oceans, locked up in polar ice caps, glaciers or in deep groundwater. Large parts of the usable water is annually recycled through the global water cycle, leaving the earth surface as vapor and returning as rain, though rarely at the same place. Seasonally and spatially variable precipitation patterns and river transporting the run-offs govern the local and regional availability of water. Water ending up in its liquid form in rivers, lakes and aquifers is called blue water. Water responsible for soil humidity has been termed green water. The literature also talks about grey and black water. Grey is polluted water and black is water contaminated by human excreta. They can both be converted into blue water again by wastewater treatment technologies. Green water is stationary, cannot be transported and is exclusively used by plants for their growth. Plant material and crops in terms of water is named virtual water which means the amount of water needed to grow the crop or plant. That water is locally lost as evapo-transpiration to the atmosphere.

About 1,500 cubic meter of water is what each person needs annually for a decent life, roughly 2 cubic meter of highest quality for drinking, 20 cubic meter for hygiene and cooking, and 250 for services and industrial needs, all of it, blue water The rest is for growing food, mainly green water. A shortage of water is compensated by food import. Food contains all the nutrients which will be excreted after consumption. Together with the fertilizers applied at the production site, these nutrients are the major polluters of rivers, lakes groundwater and coastal oceans. Water treatment to remove these pollutants requires energy. In larger cities the major part of the communities’ electricity bills is for handling water. Electricity typically originates from hydropower, coal, oil and gas firing. For hydropower rivers have to be dammed, altering flow regimes. Oil and gas are produced increasingly unconventionally and water intensive (oil sand, fracking, etc.). Two to three cubic meters of water are needed for one barrel of oil from oil sands, leaving behind highly contaminated and difficult to treat water. In semi-arid areas where currently much shale oil and gas deposits are mined, fracking activities increasingly compete for water with irrigation agriculture and larger communities. Innovations in water management focusing on pollution prevention or multiple uses of the same water through recycling and treating complex chemistries will be in demand.

These challenges will be presented based on specific cases, the vulnerabilities and weaknesses of certain links exemplified, and the needs for specific process and technology related innovative solutions identified.

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PL-06-01

A CHALLENGE FOR TOTAL SYNTHESIS: ATOM ECONOMY

Barry M. Trost

Job & Gertrud Tamaki Professor

Department of Chemistry, Stanford University, Stanford, CA 94305-5080

A major challenge for synthesis is the enhancement of efficiency. While most attention has focused on selectivity, the question of how much of what goes into the pot actually ends up as product, which I refer to as atom economy, is equally significant. This goal addresses the twin issues of better use of raw materials in order to conserve valuable resources and minimization of the generation of waste to reduce disposal issues. There are two strategic aspects. In one, efforts are made to improve existing processes. A second and, even more challenging one, is to invent new processes. This latter alternative also has the advantage of providing for new strategic concepts for constructing complex molecules that could further streamline syntheses.

The first step is to invent reactions that theoretically are capable of having maximal atom economy or nearly so. The ideal reaction is an addition. A description of a research program that asks the question of whether new addition reactions can be rationally invented is explored. A key element is the utilization of catalysis involving alkynes as key building blocks. The chemistry largely involves simple additions wherein anything else is needed only catalytically. Using a mechanism based approach, a number of new catalytic reactions is under development. The applications of some of these to interesting biomolecular targets is prominently considered and highlighted.

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PL-07-01

Designer enzymes

Donald Hilvert

Laboratory of Organic Chemistry, ETH Zürich, Zurich, Switzerland.

Protein design is a challenging problem. We do not fully understand the rules of protein folding, and our knowledge of structure-function relationships in these macromolecules is at best incomplete. Nature has solved the problem of protein design through the mechanism of Darwinian evolution. From primitive precursors, recursive cycles of mutation, selection and amplification of molecules with favorable traits have given rise to all of the many thousands of gene products in every one of our cells. An analogous process of natural selection can be profitably exploited in silico and in the laboratory on a human time scale to create, characterize and optimize artificial catalysts for tasks unimagined by Nature. Recent progress in combining computational and evolutionary approaches for enzyme design will be discussed, together with insights into enzyme function gained from studies of the engineered catalysts.

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PL-08-01

Light at the end of the Tunnel for Macromolecular Syntheses

Yusuf Yagci

Istanbul Technical University, Department of Chemistry, Maslak, Istanbul 34469, Turkey

e-mail: [email protected]

Many important processes in nature such as photosynthesis and ozone production in atmosphere are driven by light. Light induced reactions also play a central role in abroad range of macromolecular processes. Initiation of various modes of polymerization processes by photochemical methods has been widely used1 in conventional applications in coatings, adhesives, inks, printing plates, optical waveguides, and microelectronics. In this presentation, the development of new photoinitiating systems for radical2, 3, cationic4 and step-growth polymerization5, 6 will be described. Besides film forming applications, these methods can also be used in polymer syntheses. What type of polymerization mode is applicable depends on the chemical structure of the monomers used. Whilst free radicals initiates the polymerization of unsaturated polyesters and (meth)acrylic monomers, epoxy and vinyl ether based formulations are activated by a cationic mechanism. Recent relevant studies2 were devoted to make free radical and cationic photoinitiators responsive to light with wavelengths in the near UV and visible region of the spectrum With recent advances in the use of nanomaterials like metals, metal oxides and silicates in UV curing applications, it is now possible to prepare nanocomposites films with enhanced physical, chemical and biological properties. In the presentation, several synthetic methodologies for the preparation of epoxy and (meth)acrylate based formulations containing clay or metal nanoparticles7,8 will also be described. The nanoparticles are homogenously distributed in the network without macroscopic agglomeration. Applicability to both free radical and cationic systems is demonstrated. Photoinduced “Click” reactions which may potentially be used in macromolecular synthesis9, 10 will also be discussed.

References

1) Y. Yagci, S. Jockusch, N. J. Turro, Macromolecules, 2010, 43, 624

2) M.A. Tasdelen, M. Ciftci, Y. Yagci, Macromol. Chem. Phys., 2012, 213, 1391

3) M.A. Tasdelen, M. Uygun, Y. Yagci, Macromol. Chem. Phys., 2011, 212, 2036

4) G. Yilmaz, B. Iskin, F. Yilmaz, Y.Yagci, ACS Macro Letters, 2012, 1, 1212

5) B. Aydogan, Y .Yagci, L. Toppare, S. Jockusch, N.J. Turro, Macromolecules, 2012, 45, 7829

6) B. Aydogan, A.S. Gundogan, T. Ozturk, Y. Yagci, Chem.Commun., 2009, 41, 6300

7) Y. Yagci, M. Sangermano, G. Rizza, Macromolecules 2008, 41,7268

8) Y. Yagci, M. Sangermano, G. Rizza, Chem. Commun. 2008, 24, 2771

9) M.A. Tasdelen, G. Yilmaz, B. Iskin, Y. Yagci, Macromolecules, 2012, 45, 56

10) M.A. Tasdelen, Yagci Y, Angew. Chem. Int. Ed., 2013, 52, 5930

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PL-09-01

Dynamic and hybrid assemblies. Properties and applications

Luisa De Cola

Institute de Science et d’Ingénierie Supramoléculaires (I.S.I.S.), Université de Strasbourg

and KIT, Germany ([email protected])

Dynamic systems that can undergo reversible processes are of great interest for the development of new materials, sensors, biolabels…. The talk will illustrate some of the recent results on soft structures based on metal complexes able to aggregate in fibers, gels and soft mechanochromic materials [1]. The use of platinum complexes as building block for luminescent reversible piezochromic and mechanochromic materials will be illustrated. The emission of the compounds can be tuned by an appropriate choice of the coordinated ligands as well as of their aggregation in different structures. The formation of soft assemblies allows the tuning of the emission color, by pressure and temperature leading to a new class of materials possessing reversible properties.

Functional systems can also be created using inert or active nanocontainers such as microporous and mesoporous silica based nanoparticles. In particular examples using the crystalline allumino silicates, zeolite L, and mesoporous organosilicates will be discussed since these materials can act as nanocontainers and due to their biocompatibility used for biomedical applications. The different functionalization of their surface will be discussed, in particular with the aim to show that the particles can be decorated with different functional groups including biocompatible molecules and are able to perfom drug and DNA or RNA delivery inside the cell [2]. The delivery can be probed by a kinetic analyses after the nanoparticles internalization. In particular using confocal fluorescent microscopy it is possible to follow the release of each single component as well as the positioning of the nanocontainers in real time and space. Such achievement allows us to study the fate of the different units and their release time. Also it will be shown how the molecules entrapped in the ordered channels can become active components. The alignment of electroactive molecules inside the narrow channels of a zeolite L, resulted in the formation of molecular wires. The molecular wire length is tunable between 30 and 100 nm and electrical measurements on the 1D assemblies were performed. Finally an ultra-high (> 2000%) room-temperature magnetoresistance was observed applying only a few mT [3].

References

[1] C. A. Strassert, L. De Cola et al. Angew. Chem. Int. Ed., 2011, 50, 946; M. Mauro, L. De Cola et al. submitted.

[2] Z. Li, L. De Cola, C. Krampe, J. Hüve, J. Klingauf, G. Luppi, M. Tsotsalas, K. Riehemann Small, 2013, 9, 1809-1820; R. Corradini, L. De Cola et al submitted

[3] L. De Cola, W.G. van der Wiel et al. Science, 2013, 341, 257.

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O-A1-01-01

OCCURRENCE OF DRUGS OF ABUSE IN THE AQUATIC AND ATMOSPHERIC COMPARTMENTS AND ITS SIGNIFICANCE FOR THE

ENVIRONMENT AND THE SOCIETY

N. Mastroianni1, C. Postigo1, M. López de Alda1, D. Barceló1,2

1Water and Soil Quality Research Group, Department of Environmental Chemistry, Institute of Environmental Assessment and Water Research, IDAEA-CSIC, Jordi Girona 18-26, 08034,

Barcelona, Spain2 Catalan Institute for Water Research (ICRA), Parc Científic i Tecnològic de la Universitat de

Girona, Edifici H2O, Emili Grahit 101, 17003, Girona, SpainPresenting author: [email protected]

Drugs of abuse have been recently recognized as emerging environmental pollutants. These substances, either as the parent compounds or as the corresponding human metabolites, have been detected in both the aquatic and the atmospheric compartments. This presentation outlines the analytical methodologies developed by our group for their determination in water [1], sludge [2] and air [3], the results of their application in various different studies performed in Spain [1-9], and the significance of these results from the ecotoxicological point of view [6] and for the society, since their environmental occurrence can be used to evaluate consumption patterns [10,11] and/or to point out potential manufacture, traffic and/or consumption hot sites. Substances tracked in these studies include parent compounds and metabolites belonging to the classes of cocainics, amphetamine-like stimulants, opioids/opiates, LSD, cannabinoids, benzodiazepines, and alcohol. Investigated matrices include raw and treated wastewater [1,4,8], surface water [4,5,6], ground water [7], drinking water [6], sludge [2], and air particles [3,9].

Acknowledgements - This work has been financially supported by the EU (FP7 project SOLUTIONS), the Spanish Ministry of Economy and Competitiveness (SCARCE project) and the Generalitat de Catalunya (2014 SGR 418 and 2014 SGR 291). Nicola Mastroianni acknowledges the JAE Program (CSIC-European Social Funds).

References

1. C. Postigo, M. J. López de Alda, D. Barceló, Anal. Chem. 80, 3123-3134 (2008).2. N. Mastroianni, C. Postigo, M. Lopez de Alda, D. Barceló, J. Chromatogr. A 1322, 29– 37 (2013).3. C. Postigo, M. J. Lopez de Alda, M. Viana, X. Querol. A. Alastuey, B. Artiñano, D. Barceló, Anal.

Chem. 81, 4382-4388 (2009).4. C. Postigo, M. López de Alda, D. Barceló, Environ. Int. 36, 75-84 (2010). 5. A. Mendoza, S. González-Alonso, N. Mastroianni, M. López de Alda, D. Barceló, Y. Valcárcel,

Chemosphere 95, 247-255 (2014).6. A. Mendoza, J.L. Rodriguez-Gil, S. González-Alonso, N. Mastroianni, M. López de Alda, D.

Barceló, Y. Valcárcel, Environ. Int. (submitted)7. A. Jurado, N. Mastroianni, E. Vazquez-Suñe, J. Carrera, I. Tubau, E. Pujades, C. Postigo, M. Lopez

de Alda, D. Barceló, Sci. Total Environ. 424, 280–288 (2012).8. C. Postigo, M.J. Lopez de Alda, D. Barceló, Environ. Int. 37, 49–55 (2011).

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O-A1-02-01

MONITORING OF HUMAN EXPOSURE TO CONTAMINANTS OF EMERGING CONCERN

Adrian CovaciToxicological Center, University of Antwerp, Universiteitsplein 1, 2610 Wilrijk, Belgium

Presenting author: [email protected]

Contaminants of emerging concern are a broad category of chemicals, previously unknown or unrecognized as being of concern, but which, because of their potential toxic effects associated with human exposure, are under increasing scrutiny. We present the most relevant contaminants of emerging concern, together with an overview of the available analytical methods, toxicity data and biomonitoring studies in humans (1). Such contaminants include various brominated and phosphorous/chlorinated flame retardants, phthalate substitutes (e.g. diiso-nonyl cyclohexane-1,2-dicarboxylate-DINCH or O-acetyl tributyl citrate-ATBC, and tri-2-ethylhexyl trimellitate-TETM), bisphenols (e.g. bisphenol-S, -F, -B and others), personal care products or polysiloxanes.Current understanding of these emerging contaminants often contains significant gaps, including their toxicity, occurrence, human exposure, bioaccumulation, and biotransformation mechanisms. Critical issues and challenges are discussed, together with recommendations for further improvement in particular cases (e.g. metabolites of phthalate substitutes, bisphenol-S). The rather limited availability of analytical standards, of labeled internal standards, and of certified reference materials constitutes a major impediment in the widespread biomonitoring of these contaminants. For the discussed contaminants, chromatography and mass spectrometry are the analytical techniques of choice, because of their selectivity and sensitivity for measurements at (sub) ng/g levels. There is also an immediate need for interlaboratory comparison exercises which should include newer contaminants. An important issue during the setup of a biomonitoring study is the selection of appropriate biomarkers of exposure for each contaminant of interest. In the absence of knowledge regarding the biotransformation pathways in humans, various in vitro and in vivo models can be used to determine the relevant metabolites to be monitored as key aspects of further development of this field of research. There is also missing information regarding the relative importance of various exposure pathways and the multiple factors which influence the magnitude of these exposures. By far, there is a lack of standardized testing of endpoint toxicity for different groups of chemicals which makes the comparison of toxic effects and health issues for various chemicals very difficult, if not impossible.

References1. A.C. Dirtu, N. Van den Eede, G. Malarvannan, A.C. Ionas, A. Covaci A (2012) Analytical methods for emerging organic contaminants in human matrices. Anal Bioanal Chem 404, 2555-2581 (2012).

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O-A1-03-01

Strategies To Characterize Polar Organic Contamination in the Aquatic Environment– Exploring the Capability of High-Resolution Mass Spectrometry

Juliane Hollender

Eawag, Swiss Federal Institute of Aquatic Science and Technology, 8600 Dübendorf, Switzerland

[email protected]

Polar organic micropollutants such as pharmaceuticals have moved increasingly into the focus of environmental scientists, regulatory agencies, and politicians. To meet the analytical challenges of a mixture of many known and unknown compounds at low concentrations in complex matrices such as wastewater or sediment, the coupling of LC to high resolution mass spectrometry (HRMS) with high mass accuracy following appropriate ionization (ESI, APCI, APPI) is becoming a powerful method. In this presentation, the features, advantages, and limitations of LC coupled to HRMS for three conceptually different approaches are illustrated using selected studies in the field of the natural as well as engineered aquatic environment. These approaches include: (i) quantitative target analysis with reference standards; (ii) suspects screening without reference standards; and (iii) non target screening for unknowns using tailor-made software and workflows [1].

References

1. M. Krauss, H. Singer, and J. Hollender. LC-high resoluton MS in environmental analysis: from target screening to the identification of unknowns. Anal. Bioanal. Chem. 397: 943-951 (2010).

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O-A1-04-01

Bioaccumulation of Selected Halogenated Organic Flame Retardants in the Lake Ontario Food Web

B. de Jourdan1, D.C.G. Muir2, C. Teixeira2, X. Wang2, M. Keir3, S. Backus3

1University of Guelph, School of Environmental Sciences, Guelph, Canada2Environment Canada, Aquatic Contaminants Research Div., Burlington ON L7R 4A6

3Environment Canada, Water Quality Monitoring and Surveillance, Burlington ON Presenting author: [email protected]

Studies of persistent and bioaccumulative commercial chemicals and byproducts in aquatic food webs of remote lakes and in open waters of large lakes, such as the North American Great Lakes, have the potential to distinguish truly “bad actors”. These chemicals must have phys-chemical properties and characteristics which make them persistent and bioaccumulative in top predators. In this study the bioaccumulation and concentrations in surface waters of a wide range of non-legacy halogenated organic compounds (HOCs) was determined in the Lake Ontario food web. The same HOCs were also determined in lake waters and zooplankton from Lake Erie and a large, remote, inland lake (Lake Opeongo in Algonquin Park, ON). Large volume samples of surface waters (100 L; 4 m depth) were collected over the period 2006-2010 at mid-lake sites in each lake by direct pumping through a glass fiber cartridge followed by primary and secondary XAD-2 resin columns. Zooplankton (>100 um) and mysids were obtained by vertical hauls at the same sites as water while forage fish and lake trout from Lake Ontario were obtained in fall collections. Extracts were screened for 27 individual BDEs (Br3-Br10) and 30 other HOCs (Br3-Br6 compounds/ PBDE replacements and chlorinated flame retardants) using GC-electron capture negative ion mass spectrometry (GC-EC NIMS) with a HP-5MS and RTX-1614 capillary columns. DecaBDE was the predominant HOC present in Lake Ontario water with concentrations in the “dissolved” phase (i.e. passed through a 1.2 µm filter cartridge and extracted by XAD resin) averaging 109 pg/L. Particulate phase concentrations of DecaBDE averaged 650 pg/L, indicating that about 85% was on filtered particles. The predicted water solubility of decaBDE is 0.03 pg/L using the WSKOW QSPR in EPISuite [1]; therefore it is likely that decaBDE is associated with nano-particles (< ~ 1 µm) that pass through the filter rather than being truly dissolved. Other HOCs detectable in Lakes Ontario and Erie included Dechlorane Plus, 1,3,5-tribromo-2-methoxy-4-methylbenzene (Br3MeBz), pentabromo-ethylbenzene (PBEB), and 2,3-dibromopropyl- 2,4,6-tribromophenyl ether (DPTE), although concentrations were in the low or sub-pg/L range and near or at MDLs. A wide range of Br3-Br6 compounds were detected in zooplankton and mysis from Lake Ontario including Br3MeBz, 1,3,5-tribromobenzene (TBB), tetrabromoxylene (TBX), bis(tribromophenoxy)-ethane (BTBPE), PBEB, DPTE, pentabromocyclododecene (PBCDD), undecachloro-pentacyclooctadecadiene (aCl11DP). BDE47, BDE153, Br3MeBz and PBCDD had the highest trophic magnification factors in the Lake Ontario food web based on the slope of the log (lipid wt) concentrations versus trophic level. TBX, 1,3,5-TBB and BTBPE showed trophic dilution while other compounds e.g. BDE202 (and other hepta- and octaBDEs) were detectable in most samples but showed limited increases with trophic level.

[1] US EPA. Exposure Assessment Tools and Models, Estimation Program Interface (EPI) Suite Ver 4.1. (US Environmental Protection Agency, Office of Pollution Prevention and Toxics. Washington, DC, 2011).

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O-A1-05-01

UNDERSTANDING RISKS OF FISH ON PROZAC AND OTHER HARBINGERS OF AN URBANIZING WATER CYCLE

Bryan W. Brooks

Baylor University, Waco, Texas , USA


Footprints of expanding metropolitan areas extend throughout watersheds and ultimately encompass smaller order tributaries. Such population densities dictate new water reclamation plants, which discharge effluents to headwater streams, dramatically modifying instream hydrology, particularly where ephemeral streams are normative. An urbanizing water cycle is often realized in these regions. Our research has focused on effluent-dominated and dependent systems, which may result in worst case environmental risks to pharmaceuticals and other industrial chemicals. A decade ago, we reported observations of common antidepressants accumulating in fish from an effluent-dominated stream. This study was termed “Fish on Prozac”. Here I present some scientific lessons learned from our studies of urban aquatic ecosystems, and pharmaceuticals in the environment, including opportunities for research, management, environmental education and public outreach. Using probabilistic hazard assessment and fish plasma modeling analyses, I further predict selective serotonin reuptake inhibitors and tricyclic antidepressants to result in therapeutic hazard to fish (e.g., internal fish plasma levels of a drug equaling a mammalian therapeutic dose) when exposed to surface water concentrations well below 1 ug/L, a common trigger value for regulatory environmental assessments.

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O-A2-01-01

Emerging Contaminants in Water Resources: Fate Studies and Assessment for Drinking Water Supply

H.-J. Brauch, F. Sacher

DVGW Water Technology Center, 76139 Karlsruhe, Germany


The occurrence of emerging contaminants in water resources used for drinking water production and the respective handling of information and assessment of analytical data are of major concern for environmental and health institutions as well as for water suppliers. Reasons for their presence in the water cycle are the increasing production and usage of man-made chemicals within the past 50 years as well as the inadequate waste disposal and removal in waste water treatment plants and inefficient mea-sures to prevent their inputs in the aquatic environment. Moreover, the enormous progress of analytical equipment and methods led to findings of a huge number of emerging contaminants in low concentra-tions (ng/l) in wastewater, surface water, groundwater and even drinking water.

A management approach will be presented that combines the results of monitoring activities and lab-scale experiments with general information on physical, chemical and biological properties of individ-ual chemicals under investigation. Toxicity data are also needed which are provided by WHO as well as by national health organizations. The main objective of this approach is to provide water suppliers with reliable information to predict the fate of emerging contaminants during natural and technical steps of drinking water treatment. Within the past years, fate studies have been performed for various pharma-ceuticals, pesticides, perfluoro compounds, artificial sweeteners etc. [1-4].

As for most of this compounds no individual threshold values or maximum contaminant levels exist, the Federal Environmental Agency (UBA) in Germany supports water supplier on request. It gives recommendations by setting health-related indication values (HRIV) for emerging contaminants in drinking water. These HRIV are often in the range between 0.1 - 3 µg/l. The UBA recommendations fit well with the well-known TTC (threshold of toxicological concern) concept which is applied in many countries worldwide. Furthermore water suppliers and their international associations advocate for comprehensive monitoring programs, precautionary measures for the protection of the aquatic environ-ment as well as for up-grade of wastewater treatment plants.

References

1. M. Scheurer, A. Michel, H.-J. Brauch, and W. Ruck, Water Res. 46, 4790 (2012)

2. F. Th. Lange, M. Scheurer, and H.-J. Brauch, Anal Bioanal Chem 40, 2503 (2012)

3. H.-J. Brauch, and F. Sacher, Water Res. 1, 17 (2011)

4. F. R. Storck, C. K. Schmidt, F. Th. Lange, J. Henson, and K. Hahn, Journ. AWWA 104, 35 (2012)

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O-A2-02-01

SOURCES AND TRANSFER OF EMERGING HALOGENATED CONTAMINANTS ACROSS THE FOOD CHAIN

J. Hajslova, J. Pulkrabova, D. Lankova

Institute of Chemical Technology, 16628 Prague, Czech Republic


Continuous industrial development has resulted in an increasing production of various types of chemicals and their subsequent release into the environment. While most of the earlier monitoring studies focused on various chlorinated persistent organic pollutants (POPs), in the recent decades, toxicological concerns emerged on the ubiquitous occurrence of fluorine and bromine containing com pounds that may also accumulate in food chains. The high volume production of perfluoro alkylsubstances (PFASs) and brominated flame retardants (BFRs), the latter represented mainly by polybrominated diphenylethers (PBDEs), hexabromo cyclododecanes (HBCDs) and tetrabromobisphenol A (TBBPA), have led to their widespread distribution in the environment. As regards to PFASs, due to their unique characteristics such as chemical inertness, stability, hydrophobicity and lipophobicity, they are used in a variety of industrial and consumer applications while BFRs are used to reduce the flammability of treated materials. Non-occupational human exposure to PFASs and BFRs, that may occur through a variety of pathways including inhalation of contaminated dust particles or food drinking water ingestion, has been clearly documented by findings of these chemicals and their (bio)transformation products in human tissues and fluids including plasma and breast milk. The latter matrix is a widely used bioindicator that can be used to assess the body burden of these environmental pollutants especially with regard to its importance as the first food for the new born. To enable assessment of the health risks for humans, European Food Safety Authority (EFSA) launched at the end of last decade the call for providing more information on these ´emerging´ contaminants.

In the first part of this presentation, the overview of advanced analytical strategies (mainly based on hybride high resolution mass spectrometry, HRMS/MS) applicable for multi-analyte/ multi-matrix analyses will be provided. In the next phase, a number of case studies focused on the transport of a wide range of PFASs, BFRs and their metabolites across food chain will be presented. Worth to notice that dietary intake has been documented to be the major source of humans´ exposure to these hazardous chemicals; regarding the contamination level in the analyzed food commodities following order decreasing was observed within EU PERFOOD project (http://www.perfood.eu): seafood > pig/bovine liver >> freshwater/marine fish > hen egg > meat >> butter.

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O-A3-01-05

SUSTAINABLE AND SAFE RESOURCE MANAGEMENT: SINKS AS LIMITED RESOURCES?

P. H. Brunner1, D. Vyzinkarova1

1Vienna University of Technology, A-1040 Vienna, Austria

[email protected]

During the so called Anthropocene, the per capita as well as the global material turnover provided to satisfy human demand have risen to previously inconceivable amounts. While the supply of materials has been studied, optimized, and managed by different disciplines such as mining, engineering, and economics for centuries, little attention has been paid to the safe disposal of these materials in a comprehensive way.

Materials are “lost” from the anthroposphere by several pathways: As off-products such as off-gas from vehicles or industrial processes, as products of wear, corrosion and erosion from surfaces, and as wastes from households, industry, and agriculture. After treatment, a certain fraction of these material flows inevitably ends up in water, air, or soil. There are several examples that show that these flows may exceed the capacity of regional as well as global sinks. Most prominent - but not the only - cases are greenhouse gases and the resulting climate change, and CFCs and the decrease of the ozone layer.

In this paper, we advocate to investigate comprehensively into the back end of the anthropogenic metabolism, and to link resources to sinks in an all-embracing manner. Such an assessment is necessary for early recognition of overloading of sinks, for setting priorities in waste and environmental management, and for giving guidance for resource extraction and the material design of human activities. Without comprehensively linking resource extraction, stock of materials in the anthroposphere, and losses/disposal of materials into sinks, it may well be that sinks will become a limiting resource for the long-term development of the anthroposphere.

There are many challenges in this new field of research. From a methodological point of view, the following questions arise: How can “sinks” and “final sinks” - as antonyms to “sources” - be defined? What are appropriate sinks for the various classes of substances, and how can the carrying capacities of sinks be determined? What kind of metric allows measuring the flows to appropriate/inappropriate sinks, are “sink indicators” feasible?

For materials management in view of sink constraints, key questions are: Which sink capacities are necessary for accommodating all off-flows from human activities? What are todays sink requirements on a regional and global scale, and how will they change in the future when today’s large stock of hazardous substances has to be disposed of? Is general sink overloading to be expected, or will this be an individual phenomenon for a few single substances? How can potential sink constraints be overcome (prevention, design for final sinks, new waste disposal technologies)?

Answers to these questions will be crucial for sustainable resource management and environmental management. They are an essential base for planning and operating cities and regions. Particularly waste management, which is a key filter between human activities and the environment, will benefit from this research. The paper will address these questions on a general level as well as by specific case studies.

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O-A3-02-03

CARBON SEQUESTRATION IN THE UNITED STATES:

USING BIOGEOCHEMISTRY TO IMPROVE OUR

UNDERSTANDING OF THE ENVIRONMENTAL RISKS

G. Lowry*, A. Karamalidis, K. Gregory, A. Burant, D. Gulliver.

Civil & Environmental Engineering, Carnegie Mellon University, Pittsburgh, PA, USA

*[email protected]

Carbon capture, utilization, and sequestration (CCUS) technology is proposed as a means to help mit-igate climate change and impacts from increasing rates of CO2 release from emission point sources. CCUS has been studied in the United States and globally for several decades, but only recently plau-sible paths for CCUS have emerged. This includes the capture of CO2 from stationary point sources, compression, transport, and storage in deep underground saline formations, un-minable coal seams, basalt formations, organic-rich shale basins, and oil and gas reservoirs. Eight demonstration projects in the United States are ongoing or scheduled to sequester at least 1MM tones CO2 each. In addition, a large oxy-fired coal plant with CO2capture and sequestration has been proposed.

The risks associated with long-term subsurface storage of CO2are currently poorly understood. In particular, the biogeochemical processes controlling risks, such as CO2 or CO2-saturated brine leakage, CO2 impacts on deep subsurface microbiology or induced release of contaminants, are not fully eluci-dated. In the US, the National Risk Assessment Partnership (NRAP) has been formed to determine and to quantify these risks. This includes the formation of national network of models to predict risks at all steps of the sequestration process and into the next 1000 years, including leakage from abandoned wells, through proposed seal rocks, and the risks of migration of inorganic and organic contaminants to overlying water bodies and groundwater wells. The effects of CO2 injection on the native microbial communities and the associated effects on water quality are also currently being explored. Finally, methods to offset the costs associated with carbon capture and storage through storage in depleted oil reservoirs coupled with tertiary oil recovery are being considered. The most significant remaining challenges include ensuring the long-term storage capacity and security under the influence of dynamic (bio)geochemistry, stimulated biotic and abiotic mineralization to maximize storage volumes and se-curity, robust monitoring technology, and repair and mitigation strategies for various leakage scenarios

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O-A4-01-01

Interplay between oxidant stability and efficiency of micropollutant abatement in conventional and advanced oxidation processes

Yunho Lee1, Urs von Gunten2

1School of Environment Science and Engineering, GIST-Gwangju Institute of Science and Technology, 500-712, Gwangju, Republic of Korea

2School of Architecture, Civil and Environmental Engineering (ENAC), Ecole Polytechnique Fédérale de Lausanne (EPFL), CH-1015, Lausanne, Switzerland


Oxidation processes are widely applied in water treatment for disinfection and oxidation purposes. Possible chemical oxidants in water treatment are chlorine, chlorine dioxide, ferrate, ozone, and permanganate as selective oxidants and hydroxyl radical as a less selective oxidant. In recent years, oxidation processes have received increasing attention as potential tools to eliminate various organic micropollutants in enhanced wastewater or drinking water treatment. The efficiency of micropollutant elimination depends on the following aspects: 1) reactivity of an oxidant with a target micropollutant and water matrices-kinetics, 2) removal of undesirable effects of a micropollutant after structural transformation, and 3) possible formation of undesirable byproducts from the reaction of an oxidant with water matrix components. In this talk, the kinetic aspects of micropollutant transformation efficiency will be mainly discussed. The transformation efficiency of micropollutants can be assessed or predicted by the integrated form of the second-order kinetic equation for the reaction of an oxidant (Ox) with a micropollutant (P), i.e., [P]/[P]0 = exp(-kò[Ox]dt) in which k is the second-order rate constant and ò[Ox]dt is the time-integrated oxidant concentration (oxidant exposure that represents the oxidant stability). Many second-order rate constants are available in literature for the reaction of the aforementioned oxidants with various organic compounds including micropollutants. The kinetic information indicates that the selective oxidants react only with some electron-rich organic moieties (ERMs), such as phenols, anilines, olefins, organic sulfur, and deprotonated-amines. Hydroxyl radicals (·OH), in contrast, show a nearly diffusion-controlled reactivity with almost all organic moieties (k ³ 109 M-1 s-1). Quantitative structure-activity relationships (QSARs) based on Hammett or Taft Sigma constants were developed for the selective oxidants and could be used to predict the second-order rate constants for various micropollutants containing ERMs. For ·OH, the group contribution method has been developed for the prediction of second-order rate constants. Due to a competition for oxidants between a target micropollutant and water matrix (i.e. dissolved organic matter-DOM), a higher reaction rate constant with a micropollutant does not necessarily mean a more efficient transformation. In addition, the competition disappears rapidly for the selective oxidants after the ERMs present in DOM are consumed. In contrast, for ·OH, the competition is practically the same during the entire oxidation. This explains why selective oxidants can be more efficient than ·OH for transforming micropollutants with ERMs, while ·OH are effective for transforming micropollutants even without ERMs. The chemical kinetics approach described above was applied to predict the transformation efficiency of various micropollutants during ozonation of municipal wastewater effluents (10 municipal wastewater effluents + one hospital wastewater effluent). Consistent eliminations as a function of the DOC-normalized specific ozone dose (gO3/gDOC) were observed for micropollutants with similar ozone and ·OH rate constants. Micropollutants could be classified into five groups having characteristic elimination patterns accordingly to their ozone and hydroxyl radical rate constants. The transformation efficiencies of the selected micropollutants could be predicted based on their ozone and ·OH rate constants (predicted or taken from literature) and the determined ozone and ·OH exposures. Consistent molar ·OH yields were observed for the same gO3/gDOC (e.g., 21±3% for gO3/gDOC = 1.0). In addition, the rate constant for the reaction of ·OH with effluent organic matter were found to be quite constant ((2.1±0.6)´104 (mgC/L)-1 s-1). Reasonable agreements between the measured and predicted transformation levels of micropollutants were found. These data clearly demonstrate that the proposed chemical kinetics method can be used for a generalized prediction of micropollutant transformation during wastewater ozonation.

Keywords: oxidation, ozone, chlorine, hydroxyl radicals, ferrate, kinetics, micropollutant ReferencesLee, Y., von Gunten, U. (2010) Oxidative transformation of micropollutants during municipal wastewater treatment: comparison of kinetic aspects of selective (chlorine, chlorine dioxide, ferrateVI, and ozone) and non-selective oxidants (hydroxyl radicals). Water Research, 44, 555-566.Lee, Y., von Gunten, U. (2012) Quantitative Structure-Activity Relationships (QSARs) for the Transformation of organic micropollutants during oxidative water treatment. Water Research, 46, 6177-6195.Lee, Y., Gerrity, D., Lee, M., Bogeat, A.E., Salhi, E., Gamage, S., Trenholm, R.A., Wert, E.C., Snyder, S.A., von Gunten, U. (2013) Prediction of micropollutant elimination during ozonation of municipal wastewater effluents: Use of kinetic and water specific information. Environmental Science & Technology, 47, 5872-5881.Lee, Y., Koalova, L., McArdell, C.S., von Gunten, U. Prediction of micropollutant elimination during ozonation of a hospital wastewater effluent. Water Research, submitted

AcknowledgementsThe Basic Science Research Program through the National Research Foundation of Korea (NRF-2012R1A1A1010985) is acknowledged for supporting this presentation.

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O-A4-02-01

Combined Ozone Based Catalytic Processes for the Degradation of Organic Micropollutants

F.J. Beltrán

Departamento de Ingeniería Química y Química Física. Universidad de Extremadura. 06006 Badajoz. Spain


In this work a review of, possibly, the last ozone involving advanced oxidation processes (O3AOP), combination of ozone and catalysts and radiation to remove contaminants from water, is presented. Research on ozone processes increased after the 1990s with the application of catalysts which constituted other new O3AOP that took the name of catalytic ozonation. Heterogeneous catalytic ozonation can be classified according to the presence or absence of another important agent: UV radiation. Thus, the process is then called photocatalytic ozonation. Figure 1 is a bar graph with the variation of the number of research articles on catalytic and photocatalytic ozone processes between 2000 and 2013.

Figure 1: Number of research articles on ozone catalytic processes published between 2000 and 2013

Non-photolytic processes can also be classified according to the nature of catalysts: those with metals in any form and those using activated carbons [1]. Photocatalytic ozonation is a synergistic process involving photocatalytic oxidation [2] and ozonation. Fundamentals and examples of these O3AOP are presented.

Acknowledgement

The author thanks the Spanish CICYT and Feder funds for the economic support through project CTQ2012-35789-C02-01.

References

1. F.J. Beltrán, Ozone and solid catalysts for the treatment of water pollutants in Recent research developments in Environmental Technology (A. Gil y S.A. Korill: editors), Transworld Research Network, (Kerala, India, pp1-30, 2008).

2. D.S. Bhatkhande, V.G. Pagarkar, A.C.M. Beenackers, J. Chem. Technol. Biotechnol., 77, 102-116, 2001.

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O-A4-03-01

Identification of transformation products formed during electrolysis and ozonation

T.A. Ternes, C. Prasse, C. Lütke EverslohFederal Institute of Hydrology, Department Aquatic Chemistry, 56068, Koblenz, Germany


Oxidative processes such as ozonation and electrolysis have been shown to eliminate a wide spectrum of micropollutants from wastewater. Even though a complete mineralization is often not feasible due to the high energy consumption, oxidation of bio-recalcitrant moieties might lead to further degradation in subsequent biodegradation.In the current studies the transformation of selected contrast media and tramadol was investigated during oxidative processes such as ozonation and electrolysis. The transformation products (TPs) formed were elucidated by high-resolution mass spectrometry and NMR. In the past the elucidation of TP formation was extremely time consuming or even impossible for chemical processes due to the limited analytical capabilities. This situation changed in the last 15 years. Modern hybrid mass spectrometry systems (e.g. FT-MS, ion trap MS, SF-MS, Q-MS, TOF-MS) provide the accurate masses of TPs and deliver information of mass fragments which can be used to identify the chemical structure. One possibility to confirm the chemical structure of a TP is the nuclear magnetic resonance spectroscopy (NMR). However, a drawback of NMR today is still the elevated quantity needed of a relative pure isolated standard.Electrochemical treatment using boron-doped diamond electrodes provides a way to generate highly reactive hydroxyl radicals and therefore facilitate degradation of various micropollutants such as iopromide. Although cathodic reduction of the latter easily leads to dehalogenated derivatives, it was found that mineralization takes place almost exclusively via anodic reactions without formation of significant amounts of oxidation products.[1] In contrast to that, electrolysis of tramadol furnished a series of anodically formed TPs. Besides typical oxidation and hydroxylation reactions, chlorination of tramadol was observed due to in-situ generation of active chlorine. Other transformations, such as demethylations were found to occur in analogy to previous studies using ferrate(VI) or ozone as oxidants.[2]The German BMBF project TransRisk (www.transrisk-projekt.de) investigates the suitability of ozonation and subsequent biofiltration and activated carbon filtration for the elimination of organic micropollutants from conventional treated wastewater. Special emphasis is placed on the elucidation of TPs formed during an ozonation step and their removal during subsequent treatment. Tramadol-N-oxide, the main TP being formed during ozonation of tramadol has also been observed in the effluent of the ozonation pilot plant with concentrations in the low ng/L range. In contrast to activated carbon filtration, tramadol-N-oxide was not completely eliminated in subsequent treatment by biofiltration indicating its biological stability. In addition, the increased polarities of oxidative TPs might also result in a lower sorption affinity to activated carbon. One example is COFA, a TP formed during ozonation of carboxy-acyclovir, a biological TP of the antiviral drug acyclovir [3], which was detected in ozonated waters as well as biofilter and activated carbon filter effluents in concentrations up to 5 µg L-1.

References1. C. Lütke Eversloh, N. Henning, M. Schulz, T.A. Ternes, Water Res. 48, 237 (2014).2. S.G. Zimmermann, A. Schmukat, M. Schulz, J. Benner, U. von Gunten, T.A. Ternes, Environ. Sci. Technol. 46, 876 (2012).3. C. Prasse, M. Wagner, R. Schulz, T.A. Ternes, Environ. Sci. Technol. 46, 2169 (2012).

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O-A4-04-01

VIRUS DISINFECTION BY ADVANCED OXIDATION – CAN WE KILL THEM ALL?

Tamar Kohn

Ecole Polytechnique Fédérale de Lausanne, School of Architecture, Civil and Environmental Engineering, Laboratory of Environmental Chemistry, Lausanne 1015, Switzerland


Despite the remarkable progress accomplished in water and wastewater treatment over the past decades, pathogens in drinking and recreational water continue to pose a threat to public health in both industrialized and developing nations. Pathogenic viruses present a particular challenge for microbial water quality because they are excreted in very high numbers from infected patients, while their infectious dose can be very low. Both conventional disinfection processes as well as advanced oxidation technologies (AOTs) have proven useful in reducing the number of infectious viruses, though the disinfection success varies greatly between disinfectants. For example, human adenovirus is relatively resistant to UV, but is readily inactivated by oxidants, including those encountered in AOTs. This indicates that UV and oxidants inactivate viruses by different modes of action, though the details of these processes are not understood.

In this presentation, new insights into the mechanism of action of UV and oxidants on enteric viruses are discussed. Enteric viruses consist of a single or double strand of RNA or DNA encapsulated in a protein capsid, and each of these components can serve as a disinfectant’s main target. Protein mass spectrometry and quantitative PCR were employed to monitor the effect of disinfection on these viral components. The observed damage was then linked to losses in vital virus functions, such as host cell entry or genome replication.

Results show that for UV, the viral genome is the main target, while most oxidants target both viral genome and proteins. Genome damage readily led to inactivation by inhibiting the virus’ ability to replicate inside the host. In contrast, protein damage was often found to be inconsequential, unless it occurred in regions directly involved in host attachment. This detailed insight into disinfection mechanisms allows us to understand instances of disinfection failure: partial resistance to disinfection by oxidants can be achieved by either forming large viral aggregates, or by deposition of shielding disinfection products onto the virus surface, thus preventing access of the oxidants to crucial protein sites. Viral aggregation also offers some protection against UV, by facilitating recombination of damaged genome segments. Finally, repeated exposure to UV or oxidants leads to resistant virus populations. This could be related to few mutations, which had important consequences on the stability of vitally important regions in the viral genome or proteins.

Ultimately, the outcomes of this work allow us to assess potential pitfalls associated with virus disinfection by AOTs, and enables us to design optimal treatment strategies to achieve the best possible virus disinfection.

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O-A4-05-01

Title: Effects of Salts on the Destruction of Contaminants in Saline Waters by Advanced Oxidation Processes and Sunlight Photolysis

William A. Mitch

Associate Professor, Department of Civil and Environmental Engineering, Stanford University

Saline wastewaters include produced waters from oil and gas operations, and brines produced from reverse osmosis treatment of municipal wastewaters during potable wastewater recycling operations. In some cases, the organic contaminants in these brines are a higher concern than the salts for limiting discharges to surface waters or beneficial reuse options. Hydroxyl radical or sulfate radical-based Advanced Oxidation Processes (AOPs) may enable broad-screen removal of organic contaminants in these brines, but the effects of radical scavenging by salts on contaminant degradation efficiency must be evaluated. The talk will discuss the effects of salts on these processes, with a particular focus on the implications of the transformation of hydroxyl or sulfate radicals to more selective halogen or carbonate radicals produced in the presence of high halide or carbonate concentrations. As most fresh surface waters eventually discharge their contaminants to estuaries, the natural photochemical fate of contaminants in estuarines is also a concern. The talk will also discuss the importance of ionic strength and seawater-relevant concentrations of halides on the indirect photochemical degradation of contaminants.

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O-A5-01-01

PERSISTENT ORGANICS IN THE ENVIRONMENT:ANALYSES METHODOLOGIES AND

CONCENTRATION LEVELS IN TURKEY

Semra G. TUNCEL,

Middle East Technical University, Chemistry Department , 06531 Ankara-Turkey

Persistent organic pollutants (POPs) including PAHs (Poly Aromatic Hydrocarbons),PCBs( Poly Chlorinated bi Phenyls) and pesticides had became a threat for enviroment in turn to human health in recent two decades.It is important to understand the chemistry of these pollutants in order to develop control strategies and policy framework.

Our group in the Middle East Technical University has been studying POPs composition in various environmental matricies in Turkey since 1994.

The extraction procedures for the determination of moderate level polycyclic aromatic hydrocarbons

(PAH) and pesticides in soil, water , plant and sediment samples had been optimized and validated .

The methods optimized were soxhlet extraction, ultrasonic bath extraction, solid phase extraction and solid phase micro extraction (SPME). In order to search out the main factors affecting extraction efficiencies of the methods, factorial design was used. The best extraction method was chosen and optimum values for main factors were selected for the development of the extraction methods used for PAH and pesticides determination in different sample matrix. As an analytical tool GC_MASS or GC_flame ionization detectors.

Optimized and validated methodologies are used to determine POPs in the air of capital city Ankara, sediments of Mediterranean , well water, soil and lastly in the exported agricultural products.

Concentration levels in the above cases will be presented, compared with other countries and discussed considering their sources and effects on the natural environment and human health.

Various conclusions we derived from 20 years of our research in the major parts of the country will be presented in this talk.

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O-A5-02-01

Physical and Chemical Properties of Aerosols in the Mediterranean and Their Impact on Regional Climate

G. Kallos, J. Kushta, C. Spyrou, C. Kalogeri, N. Bartsotas

University of Athens, School of Physics, Atmospheric Modeling and Weather Forecasting Group – AM&WFG. [email protected]

Airborne particles of anthropogenic and/or natural origin have certain direct and indirect effects in the atmosphere. Aerosols interact strongly with solar and terrestrial radiation in several ways. By absorbing and scattering the solar radiation aerosols reduce the amount of energy reaching the surface. Aerosols enhance the greenhouse effect by absorbing and emitting outgoing long wave radiation. Forcing by dust and other natural aerosols exhibit large spatial and temporal variability due to their lifetime and diverse optical properties.

In this presentation we discuss the complex direct, semi-direct and indirect links and feedbacks between natural aerosols, radiation budget and the meteorological and chemical state of the atmosphere. The results of a fully coupled atmospheric modeling system (RAMS/ICLAMS) are discussed. The capabilities of this modeling system include the online coupling between chemical and meteorological processes, as well as the explicit treatment of cloud condensation, giant and ice nuclei (CCN, GCCN, IN), and size and humidity dependent optical properties for aerosols. The results from this work show that the presence of mineral dust leads to a linear reduction in solar radiation and nonlinear increase in net downward longwave radiation that is larger during daytime than nighttime. The magnitude of change in the radiation budget is determined by the vertical structure of the dust cloud and mainly its height. The perturbations in the radiation budget affect the air temperature and moisture vertical profile, leading to a cloud base lifting and redistribution of condensates. The explicit activation of aerosols as CCN and IN causes changes in the spatiotemporal patterns of the precipitation field during and after the event. These influences are caused more by the indirect rather than the direct and semi-direct effects. The changes in the diffuse and direct components of the radiation budget lead to a net negative effect on the photolysis rates that, in turn, alter the pollutants distribution. Ozone concentration, in particular, is affected by dust in a non-monotonous way determined by the availability of ozone precursors.

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O-B1-01-01

WHAT ABOUT CHEMISTRY AND CULTURAL HERITAGE: THE ANALYTICAL CHALLENGE

Vieillescazes Catherine

UMR IMBE, Avignon University/ CNRS/IRD/ AMU33 rue Louis Pasteur, 84000 Avignon France

[email protected]

Analytical chemistry is central to resolve topics of interest in the cultural heritage field, offering precious elements about the nature and composition of the original materials, their degradation processes that have occurred since many years. The chemical characterization of the constituting materials allows to unravel the rich information enclosed in a work of art, providing a better knowledge.

Chemistry was first applied to the conservation field in the 18th century, gradually assuming a fundamental role, due to the increased number of collections exhibited in the museums of Europe. Currently, chemistry for Cultural Heritage is employed to determine the nature of ancient materials, reveal production techniques and usage, support archaeometric studies (provenance, datation, attribution), detect causes and mechanisms of degradation, as well as develop and evaluate methods of restoration

The author will report on few applications of analytical chemistry (especially chromatographic techniques and spectroscopic methods) to materials of interest in the field of Cultural Heritage.

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O-B1-01-02

CHEMISTRY IN CULTURAL HERITAGE – FROM CHEMICAL ANALYSIS TO NANOTECHNOLOGY

Manfred Schreiner 1, 2 1 Institute of Science and Technology in Art, Academy of Fine Arts, Schillerplatz 3,

A-1010 Vienna, Austria 2 Institute of Chemical Technology and Analytics, Vienna University of Technology, Getreidemarkt 9,

A-1060 Vienna, Austria Presenting author: [email protected]

Since the very beginning of investigation, preservation, and conservation-restoration of our cultural heritage chemistry has been playing an important role in both, studying the material composition, an-cient production and art technology as well as in understanding degradation processes and developing and evaluating new materials for interventions. Already in the 18th century Martin H. Klaproth pre-sented papers concerning the material composition of Roman coins, ancient alloys, and glass [1]. The development of micro-chemical techniques and spot tests [2], which has reduced the amount of sample material required for analysis, resulted in the installation of the first museum’s laboratories at the begin-ning of the 20th cent. The booming development of instrumental techniques and electronics in the past decades has brought new analytical instruments of great perfection, which enables new horizons not only in material identification but also in origin or authenticity, technical construction and preservation of works of art. Parallel to the instrumental development also the requirements for material analysis has completely changed as nowadays so-called non-destructive or non-invasive methods are preferred, which means that no original sample material can be gained from an object. In many cases the analyt-ical procedure has to be carried out even in-situ in order to avoid climatic changes and high insurance costs due to transportation of the object to a laboratory.

Among the great variety of instrumental techniques, which have been applied for studying the elemen-tal composition of objects of art and archaeology, x-ray fluorescence analysis (XRF) has gained grow-ing interest. The high advantage is that in principle all elements (except H and He) of the periodic table can be detected and handheld instruments are available on the market nowadays, which can be brought into collections or to an archaeological site. For compound specific analysis, which is indispensable for the identification of the organic constituents in objects of our cultural heritage, infrared and Raman spectrometry have been used widely and are in principle also applicable in a non-destructive way.

In the presentation a short description of the principles of these analytical techniques is given and case studies will be discussed: analysis of pigments, quantitative analysis of Roman coins and archaeologi-cal glass as well as weathering stability and degradation phenomena of glasses with medieval composi-tion. Furthermore, the effect of the sol-gel coatings on medieval stained glass is discussed. The coating protects the glass from further weathering due to the ambient atmosphere, which would cause serious damages on the uncoated glass.

References:

1. M.H. Klaproth, Abhandlung der königlichen Akademie der Wissenschaften und schönen Künste zu Berlin, Teil Experimentalphilosophie 1792 – 1797, pp. 3-14 and 71-78.

2. F. Feigl, Spot tests in inorganic analysis. and: Spot tests in organic analysis. Elsevier Publishing Comp., Amsterdam-Houston-London-New York, 1954.

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O-B1-02-01

A BRIEF HISTORY OF CHEMICAL EDUCATION IN TURKEY

Emre DÖ[email protected]

Chemical education in Turkey can be divided into two periods. In the first period before 1917, chemistry lessons were only given to teach necessary information about chemistry. The year 1917 was a turning point and chemistry began to be taught as a profession at technical schools. The development of chemical education in Turkey can be divided in nine detailed periods below.

1795 – 1839 (The period in which various subjects related to chemistry were taught at technical schools): The curriculum of the Imperial Military Engineering School which was established in 1795 did not include any lectures related to chemistry. Some practical information about chemistry and metallurgy were given at that school.

1839 – 1900 (The period in which chemistry was taught as an auxiliary lecture at various schools): The medical and pharmacy students took comprehensive chemistry lectures at the Imperial Medical School which was founded in 1839 and Civil Medical School which was established in 1867. At those years, chemical education was also given at other technical schools.

1900 – 1917 (The period in which chemical education was included in science education at Darülfünun [Imperial University]): Chemistry lectures continued to be given at other schools. Chemistry education began to be given at Darülfünun (Imperial University) which was founded in 1900; but it was included in the scope of general science education. Towards the end of this period, a chemistry laboratory was established at the Faculty of Science.

1917 – 1933 (The period of Chemical Education at Darülfünun [Imperial University] Faculty of Science): As a result of the efforts of the faculty members Dr. Fritz Arndt, Dr. Gustav Fester and Dr. Kurt Hoesch who were invited from Germany in 1915, an independent chemistry department was established at Darülfünun (Imperial University) Faculty of Science in 1917. It was the first time that the diploma in science of chemistry was given.

1933 – 1943 (The period in which chemistry was only taught at Istanbul University Faculty of Science): In this period, chemical education was transformed into education of chemical engineering.

1943 – 1958 (The period in which chemistry was taught at Ankara Faculty of Science besides Istanbul University): Professional chemistry education began to be given at Ankara Faculty of Science which was opened in 1943. This education was transformed into chemical engineering in 1948.

1958 – 1982 (Pluralist Period): In universities, academies, colleges and private colleges which were opened in this period, undergraduate education in chemistry, training of chemistry teachers and chemical engineering was taught with different approaches.

1982 – 1988 (Monotype Education Period): In this period, monotype education system was adopted at universities by the instructions of the Council of Higher Education.

After 1988 (Back to Pluralist Education again): As a result of change in the regulation of the Council of Higher Education in 1988, universities began to establish their own different programs again.

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O-B1-02-02

HISTORIC SITES OF CHEMISTRY

C. NawaMuseum der Universität Tübingen MUT, 72070, Tübingen, Germany

Ever since the German Chemical Society, the Gesellschaft Deutscher Chemiker (GDCh), kicked off the programme “Historic Chemical Sites” in 1999, it became a huge success. Originally inspired by the “National Historic Chemical Landmark”-series of the American Chemical Society (ACS), the German Historic Sites of Chemistry Programme quickly developed a distinct and characteristic profile. Meanwhile 14 places of particular historical interest testify to the cultural heritage and to the historic roots of chemistry, fostering public appreciation for the contributions of chemistry to our daily lives [1]. In my talk, I am going to present this programme and the requirements for becoming a designated historical site. Moreover, I will introduce one edifice of particular historical interest more closely: the laboratory of Robert Wilhelm Bunsen (1811–1899) in Heidelberg. This laboratory represents Bunsen’s outstanding achievements in the realms of inorganic and early physical chemistry. At the same time, the building itself deserves attention. Built in 1854/55, Bunsen’s laboratory immediately became iconic as the most modern and best equipped laboratory in Europe. Though comparatively modest in size, the laboratory’s progressive equipment made it a model for new construction projects in Germany and beyond [2] – and it is still worth a visit today.

Figure 1: Bunsen’s laboratory. Detail from the frontispiece of H[einrich] Lang (ed.), Das chemische Laboratorium an der Universität in Heidelberg (Karlsruhe: Chr. Fr. Müller 1858).

References[1] Christoph Meinel, “15 Jahre ‚Historische Stätten der Chemie‘,” Nachrichten aus der Chemie. Zeitschrift der Gesellschaft Deutscher Chemiker 6 (to be published in June 2014). [2] Christine Nawa, “A Refuge for Inorganic Chemistry: Bunsen’s Heidelberg Laboratory,” Ambix 61:2 (2014), 115-140.

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O-B2-01-01

Building knowledge alliances: some examples from analytical sciences

Philip Taylor

Joint Research Centre IRMM, European Commission

The recent Erasmus+ programme has a key action on cooperation for innovation and the exchange of good practices. This Key Action supports Transnational Strategic Partnerships, Knowledge Alliances between higher education institutions and enterprises, Sector Skills Alliances (supporting the design and delivery of joint vocational training curricula) and Capacity Building projects to support organisations/institutions and systems in their modernisation and internationalisation process.

Such kind of activities often by nature involve different kinds of organisations and people and are hence not easy to set up as often links to other actors are missing. An example is brought from the area of Analytical Sciences. In fact, it cannot be an example of such an Erasmus+ project, but instead it is an illustration how people from research institutes, government organisations and industry can interact to set up such networks.

Knowledge and skills to perform proper analytical measurements are essential in many different areas of science and society. Better healthcare, food safety and environmental protection are just some of the ways in which accurate and reliable measurements influence our quality of life. Moreover, the competitiveness of the European economy and the smooth functioning of international trade depend on reliable measurements, which eliminate the need to duplicate or dispute testing data. Accurate measurements and standardisation are also prerequisites for technological development and innovation.

Today, there is a surging need for more accurate measurements, particularly in emerging fields such as nanotechnology, biotechnology and personalised medicine. In advanced economies, legislation puts also an ever-increasing demand on measurement capabilities, by moving towards lower detection thresholds or wishing to measure novel substances or properties that are not yet sufficiently known.

The JRC has set up knowledge-transfer schemes to ensure best practice in analytical laboratories. These activities in analytical sciences have been set up together with experts and organisations from the member states and will be explained in some detail. They include the life long learning programme TrainMiC® (www.trainmic.org) which provides assistance on how to interpret and fulfil the technical requirements of ISO/IEC-17025 in analytical laboratories as well as the educational initiative called Euromaster Measurement Science in Chemistry (www.msc-euromaster.eu).

Such activities are an interesting platform to bring together those working in industry and private laboratories, research, government institutions and academia. From such interactions there are opportunities to build strategic alliances from which all can prosper and which are very enriching.

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O-B2-02-01

Lamguages for Specific Purposes in Chemistry

Walter Zeller1, Beatrice Marinelli2

1University of Perugia 2Astyle, Linguistic Competence

The workshop is based on material developed in the context of several European Projects such as “European Chemistry and Chemical Engineering Education Workshop I, Languages for specific Purposes - Language Centres for Cultural Heritage Preservation, etc. A web portal on key competences for scientists has been implemented encompassing sections on Languages for Specific Purposes in Chemistry. Together with a fully interactive detailed learning and self-assessment section for English as a foreign language, the web Portal includes a relevant online Manual on chermistry applied to cultural heritage preservation. The Manual contains six Units with 24 lessons and is designed along the structure of writing, reading, speaking and listening. Languages supported are English, French Greek Italian Spanish and Slovene. During the workshop, attendees - students and scientists will become acquainted with learning and self-assessment sessions at level B2 in the above mentioned European languages. The eduicational methodology applied and the didactic Contents offered will be discussed with the intention to enhance communication and mobility opportunities in the multilingual European Environment.“

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O-B2-03-01

Education in Materials Science from the Chemistry perspective: overview of needs and limitations

L. A. Angurel, G. F. de la Fuente

ICMA (CSIC-University of Zaragoza) E50018, Zaragoza, Spain Presenting author: [email protected]

Materials Science is a multidisciplinary subject of great importance, because it is transversal to basically all scientific and engineering disciplines. The applications of materials are overwhelmingly diverse, covering Biomedicine, Organic and Inorganic devices, as well as engineering structures, to name just a few. These make Materials Science both, very attractive from the practical point of view, and very complex from a fundamental educational perspective.

Although Physical property studies are an intimate, well-developed and essential aspect of Materials Science, Chemistry lies at the fundamental basis of most advances in this transversal discipline. The reasons for such importance are related to the fact that reactivity between solids, thus synthesis and processing, as well as structure and microstructure, all play a key role in materials development, characterization and improvement. In fact, the relationship between Chemistry, Physics and Engineering is an identity that should be present in the design of all the new degree or master studies related with Material Science.

Chemistry must provide the tools to understand the necessary concepts that will allow future specialists to design, synthesize, process and characterize new materials. For all of that, new structural chemistry concepts which approximate reality, molecular and extended solid synthesis know-how, as well as a basic understanding of characterization methods, are all essential requirements.

An overview of the above topics will be followed by appropriate examples related to three types of processes encountered in a multidisciplinary materials environment. These will be used to stress the essential role of Chemistry in Materials Science, emphasizing present limitations and needs.

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O-B2-04-01

Education Workshop: Distributing Virtual Learning Objects In Chemistry

I. A. Kozaris1, S. Tasso2

1Aristotle University of Thessaloniki, GR 54124, Thessaloniki, Greece 2University of Perugia, IT 06123, Perugia, Italy

Presenting authors: [email protected]; [email protected]

The workshop is based on the repository of distributed learning objects established in the context of project: European Chemistry and Chemical Engineering Education Network II.

Learning objects are reusable digital resources supporting active and innovative learning. In chemistry, learning objects are self-contained presentations of teaching units explaining concepts or processes. They can be a PowerPoint presentation, an interactive application, a video, a concept map etc. The overall procedure is consistent with the European Union policy to harness information and communications technologies for developing innovative education and training practices, and improving access to all levels of education and training.

During the workshop, attendees – teachers, learners, course developers – will have the opportunity to be acquainted with the development of learning object structure and tools, and with their usability through dedicated indexing systems, such as the innovative management system G-LOREP®. In this frame, the implementation of a community dealing with distributed learning objects in chemical sciences will be harnessed, to the benefit of chemical education.

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O-B3-01-01

Writing Scientific Articles

V. Köster1ChemistryViews.org, Wiley-VCH, 69469 Weinheim, Germany


To be successful as a scientist, you are expected to share your research work with others. But how do you get from your lab book full of exciting results to a successful scientific article?This presentation will guide you step-by-step through the most important attributes of a well-written scientific paper. This includes, for example, tips on how to compose a good title and how to write a concise abstract.Additionally, you will get some insight into how a journal editor assesses your paper and what is expected from an editorial point of view.

Figure 1: How to write a successful article. Further reading, e.g., [1].

Reference1. R. Threlfall, ChemistryViews.org (2013). DOI: 10.1002/chemv.201200115

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O-B3-02-01

Sustainable chemistry – a role for a successful Europe?

Gernot Klotz 1

1CEFIC, B-1160, Brussels, Belgium Presenting author: [email protected]

Chemistry and the chemical industry are the roots of society´s path to Sustainable Development. Key Enabling Technologies like advanced materials, nano- and biotechnologies, advanced manufacturing and processing are indispensable to modern solutions for mobility, health, food, energy and the like. Chemical companies supply both essential materials for different value chains and consumer products like coatings, hygiene, cosmetics etc.

Innovation is not only about new molecules but combining chemical building blocks into products with new properties and improved sustainability along the pillars of economic, environment, social development. Sustainable Chemistry has to focus not only on feedstock, but on the sustainable production and consumption throughout the product’s life cycle.

In society and especially in public funding there is a shift from technologies support to demonstration of societal value. Open innovation, cooperation between chemists and multi-disciplinarity are essential, and require new skills. Chemistry is still seen as the hidden solution but in today´s society we have to demonstrate the value of chemistry and lead our own initiatives addressing societal challenges. Under global competition, technology leadership is key to keep and supply high quality jobs in Europe, especially because the region is short on raw materials and has high manufacturing costs. Knowledge creation through research is important, but Europe must find more efficient ways to harvest on this investment by creating jobs and growth.

References

1. Cefic Sustainability Report “The chemical industry in Europe: Towards Sustainability”, http://www.cefic.org/Cefic_Sutainability_Report2011-2012.pdf

2. Cefic Long-range Research Initiative (LRI) - http://cefic-lri.org/

3. European Technology Platform for Sustainable Chemistry (SusChem) http://www.suschem.org

4. Sustainable Process Industry through Resource and Energy Efficiency (SPIRE) http://www.spire2030.eu/

5. F3Factory - http://www.f3factory.com

6. Smart Cities - http://eu-smartcities.eu/

7. Water - http://ec.europa.eu/environment/water/innovationpartnership/

8. Skills needed for innovation http://www.cefic.org/Skills-Needed-for-Innovation

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O-B3-05-02

The Chemistry of Chocolate

Luisa De Cola

Institut de Science et d’Ingénierie Supramoléculaires (I.S.I.S.), Université de Strasbourg 8, allée Gaspard Monge, 67000 Strasbourg France ([email protected])

Chocolate is a unique food. It is solid at normal room temperature yet melts easily in the mouth leaving a pleasant and distinct taste. In this talk I will shortly present the history of chocolate from his early discovery to its introduction in Europe, in Spain in 1520. The processing of the cocoa beans from their harvesting, to their fermentation, drying, storage, roasting, cracking and grinding will be illustrated to show how complex some of the processes and analysis are. Then we will have a look at the science of chocolate, and find out about the latest research into the possible health effects of its consumption. Lastly, we’ll explore the somewhat controversial question of why chocolate make us feel so good. Chocolate contains more than 300 known compounds. Scientists have been working on isolating specific chemicals and chemical combinations which may explain some of the pleasurable effects of consuming chocolate.

Caffeine is the most well known of these ingredients, and while it’s present in chocolate, it can only be found in small quantities. Theobromine, a weak stimulant, is also present, in slightly higher amounts. The combination of these two chemicals (and possibly others) may provide the “lift” that chocolate eaters experience. The role played by stimulants as well as the effect of chocolate on health and in particular as antidepressant, and as medicine for cardiovascular diseases will be described. Finally some of the physical properties related to the crystallization and micro-assemblies of the components will be shortly discussed.

And I am sure that by the end of my talk everybody will be convinced that chocolate is indeed the food of the Gods !

[1] Coe, Sophie D. and Michael D. Coe. The True History of Chocolate. New York: Thames and Hudson, 1996.[2] Tomaso, E.d., M. Beltramo, and D. Piomelli. Brain Cannabinoids in Chocolate. Nature, 1996[3] Teubner, Christian. The Chocolate Bible. New York: Penguin Studio, 1997.[4] Beckett Stephen T. The science of chocolate. The Royal Society of Chemistry 2000

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O-C1-01-01

Orbital molecules in electronic oxides

J. Paul Attfield

Centre for Science at Extreme Conditions and School of Chemistry, University of Edinburgh, Mayfield Road, Edinburgh EH9 3JZ, UK.


‘Orbital molecules’ are weakly-bonded clusters of transition metal ions formed in orbitally-(and often charge-) ordered phases of transition metal oxides and related materials. They have become prominent following the discovery of an orbital molecule order in the low temperature structure of magnetite, Fe3O4. The electronic nature of magnetite below the 125 K Verwey transition has been an enduring mystery since it was first reported in 1939. Various charge ordered and other ground states were postulated over many decades. Our recent determination of the complex low temperature superstructure shows that it is charge and orbitally ordered to a good approximation, but with an additional orbital molecule order of three-site ’trimeron’ units [1,2,3].

Figure 1: Trimeron order in the 90 K magnetite structure. (a, left) Minority spin electron distribution and associated atomic displacements (purple arrows) within a trimeron. Orbital order at the central Fe2+ site (blue) localises the minority spin electron in one of the t2g orbitals and elongates the four Fe-O bonds perpendicular to the local Jahn-Teller axis. Weak bonding interactions transfer minority spin density into coplanar t2g orbitals at two neighbouring B sites and shorten the Fe-Fe distances. The minority spin electron density is approximated by the ellipsoid shown. (b, right) Trimeron distribution in the low temperature magnetite structure, following the experimentally observed distortions, with first approximation Fe2+/Fe3+ states shown as blue/yellow spheres and trimeron ellipsoids as in (a).

References

1. Senn, M.S.; Wright, J.P. & Attfield , J.P. Nature 481, 173 (2012).

2. Senn, M.S., Loa, I., Wright, J.P. & Attfield J.P. Phys. Rev. B 85, 125119 (2012).

3. Senn, M.S.; Wright, J.P. & Attfield , J.P. J. Kor. Phys. Soc. 62, 1372, (2013).

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O-C1-02-01

Interplay of Spins, Orbitals, Charges and Lattice Instabilities in Complex Oxides

Martin JansenMPI for Solid State Research, Stuttgart

Multinary oxides constitute a remarkably versatile and prolific class of materials. They have continued to play a major role in the fields of high temperature superconductivity (HTSC) and colossal magneto resistivity (CMR), or, more recently, multiferroics and spintronics. Although a lot of effort has gone into unraveling the phenomena of HTSC in cuprates and of CMR in manganates, no fully consistent and conclusive microscopic explanation has become available yet. In the first place, this unpleasant state is due to the high complexity of the problems resulting among others from strong electron correlation, and coupled charge, spin and orbital ordering in collective systems. Moreover, virtually all oxide materials showing HTSC or CMR include severe structural disorder, even decay into multiphase systems (phase separation, stripe formation), a fact that has impaired theoretical analyses commonly relying upon translational invariance, and has blurred experimental observations. Against this background, it would be highly desirable to employ fully periodic and chemically well defined materials as model systems for studying charge, spin and orbital ordering, either coupled or independent. We have tried to tackle this issue by providing new families of structurally and compositionally well defined oxide based functional materials displaying- Frustrated magnetic exchange interactions and orbital ordering on trigonal lattices in silver

nickelates[1]- Wigner crystallization vs. charge density waves in quasi one dimensional, mixed valent cuprates

and manganates.[2]- Lattice instabilities and competing spin structures in 3d-5d double perovskites[3]Besides full characterisations with respect to structures, physical properties and electronic structure analyses, particular emphasis has been given to aspects of solid state synthesis. In order to achieve well defined valence states and structural perfection, special, in part newly developed, synthesis protocols, e.g. the “azide/nitrate route”[4], needed to be applied.

[1] E. Wawrzynska, R. Coldea. E. M. Wheeler, I. I. Mazin, M. D. Johannes, T. Sörgel, M. Jansen, R. M. Ibberson, P. G. Radealli: Orbital Degeneracy Removed by Charge Order in Triangular Antiferromagnet AgNiO2, PRL 99 157204 (2007); G. L. Pascut, R.Coldea, P. G. Radaelli, A. Bombardi, G. Beutier, I. I. Mazin, M. D. Johannes, M. Jansen: Direct observation of charge order in triangular metallic AgNiO2 by single-crystal resonant x-ray scattering, PRL 106 157206 (2011) [2] N. Z. Ali, J. Sirker, J. Nuss, P. Horsch, M. Jansen: Spin exchange dominated by charge fluctuations of the Wigner lattice in the newly synthesized chain cuprate Na5Cu3O6 Phys. Rev. B84 035113 2011) [3] Avijit Kumar Paul, Manfred Reehuis, Vadim Ksenofontov, Binghai Yan, Andreas Hoser, Daniel M. Többens, Paula M. Abdala, Peter Adler*, Martin Jansen*, and Claudia Felser: Lattice Instability and Competing Spin Structures in the Double Perovskite Insulator Sr2FeOsO6, PRL 111, 167205 (2013); Binghai Yan, Avijit Kumar Paul, Sudipta Kanungo, Manfred Reehuis, Andreas Hoser, Daniel M. Többens, Walter Schnelle, Robert C. Williams, Tom Lancaster, Fan Xiao, Johannes S. Möller, Stephen J. Blundell, William Hayes, Claudia Felser, and Martin Jansen*: Lattice-Site-Specific Spin Dynamics in Double Perovskite Sr2CoOsO6, PRL 112, 147202 (2014)[4] M. Jansen: The Azide/Nitrate Route, a versatile and prolific procedure for the Synthesis of Alkali Oxometalates, Z. Anorg. Allg. Chem. 638 1910 (2012)

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O-C1-04-01

THE STEROCHEMICALLY ACTIVE LONEPAIR; THE JOY IT BRINGS AND THE TROUBLE IT CAUSES

Sven Lidin1

1CAS, Lund University, Getingevägen 60, 22100, Lund, Sweden Presenting author: [email protected]

The heavier p-block elements are known to exhibit stereochemically active, but chemically inert lone pairs in their lower oxidation states; Sn(II), Sb(III), Te(IV), Tl(I), Pb(II), Bi(III) and much has been written about their nature and what stabilizes them. It is an observation that in the solid state, the lone pairs tend to agglomerate into specific subspaces of the structure, often together with other non-bonding species such as halide ions. This compartmentalization of space is reminiscent of the self-organization in amphiphile systems or systems with asymmetric hydrogen bonding interactions. In systems with a small sub-volume of non-bonding entities, the bonded sub-volume normally percolates and the non-bonding sub-volumes form zero- or one-dimensional inclusions, but with increasing non-bonding volume fraction the bonded sub-volume breaks up into discreet units with limited dimensionality; sheets, rods or clusters.

The underlying principle is that units that build such systems are in some sense polar with respect to their interactions. The lone-pair elements are special because they embody this polarity within a single atom, and thus the scale at which they may form polar structures is the smallest possible. Further, the polarity of the individual atoms may be directly transferred to an electrical polarity of the entire structure unless the effect is cancelled by inversion in the structure. Lone pair chemistry is therefore a possible source for materials of interest for applications in optics and in pyro-, piezo- and ferroelectrics.

The interesting properties of lone-pair materials are thus inextricably linked to the features that lead to low dimensionality and this is also one of the challenges in their synthesis, characterization and use. In systems where the bonding sub-volume does not percolate, structural cohesion is poor and solid materials tend to form thin platelets or needles where disorder is rampant.

This lecture will cover some of the challenges that need to be addressed in order to understand the structures of lone-pair materials.

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O-C2-01-01

Novel Strategies for Combining Molecules, Clusters, and Nanocrystals into Functional Inorganic Solids

Maksym V. Kovalenko1,2

ETH Zürich, Department of Chemistry and Applied Biosciences, CH-8093, Zurich, Switzerland and Empa-Swiss Federal Laboratories for Materials Science and Technology, CH-8600, Dübendorf,

Switzerland

Chemically synthesized inorganic nanocrystals are considered to be promising building blocks for a broad spectrum of applications including electronic, thermoelectric, and photovoltaic devices. To achieve high degree of electronic coupling, the nanocrystal packing, surface chemistry and surrounding medium need to be properly designed [1].

This talk will provide an overview of the most recent developments towards functional inorganic materials built from nanocrystal building blocks. Special attention will be paid to rational combinations of inorganic molecules, clusters and nanocrystals – from synthesis strategies and surface chemistry, to self-assembly and device applications. Several examples will include nanocrystal-based materials for Li-ion and Na-ion batteries [2,3,4], infrared-active nanostructures [5], metal halide complexes as inorganic capping ligands [6] and hybrid molecular-nanocrystal superlattices [7].

1. Kovalenko, M. V.; Scheele, M.; Talapin, D. V. Science 2009, 324, 1417.

2. Kravchyk, K.; Protesescu, L.; Bodnarchuk, M. I.; Krumeich, F.; Yarema, M.; Walter, M.; Guntlin, C.; Kovalenko, M. V. J. Am. Chem. Soc. 2013, 135, 4199.

3. He, M.; Kravchyk, K. V.; Walter, M.; Kovalenko, M. V. Nano Letters, 2014, 14, 1255.

4. M. I. Bodnarchuk, K. V. Kravchyk, F. Krumeich, S. Wang, and M. V. Kovalenko. ACS Nano, 2014, 8, 2360.

5. Yarema, M.; Kovalenko, M. V. Chem. Mater. 2013, 25, 1788.

6. D. N. Dirin, S. Dreyfuss, M. I. Bodnarchuk, G. Nedelcu, P. Papagiorgis, G. Itskos, and M. V. Kovalenko. J. Am. Chem. Soc., 2014, 136, 6550.

7. Bodnarchuk, M. I.; Erni, R.; Krumeich, F.; Kovalenko, M. V. Nano Lett. 2013, 13, 1699.

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O-C2-02-01

Molecular Spintronics: The role of chemistry

E. Coronado1

1Instituto de Ciencia Molecular (ICMol). Universidad de Valencia (Spain)

Spin-based electronics is one of the emerging branches in today’s nanotechnology and the most active area within nanomagnetism. So far spintronics has been based on conventional materials like inorganic metals and semiconductors. Still, molecular electronics emerged several decades ago as a promising possibility to complement or even to replace conventional inorganic electronics when it goes nano. On the other hand, molecular magnetism has provided in recent years many examples of new magnetic molecules and multifunctional materials with tunable magnetic properties or combination of properties. In this context, molecular spintronics has recently appeared as a new field at the intersection of these two molecular fields. Its final aim is that of using molecule-based materials, or even single-molecules, as components of new spintronic systems and devices [1].

In this talk I will show the key role played by chemistry in this new area. The first example will deal with the chemical design of single-molecule magnets which can be useful as qubits in quantum computing [2]. The second example will concern the design of switchable nanodevices made on spin-crossover nanoparticles [3]. The third example will focus on the fabrication of multifunctional molecular devices exhibiting magneto-electro-luminescence (i.e., Spin-OLEDs).

References

1. J. Camarero, E. Coronado, J. Mater. Chem. 19, 1678 (2009).

2. J. M. Clemente-Juan, E. Coronado, A. Gaita-Ariño, Chem. Soc. Rev. 41, 7464 (2012).

3. F. Prins, et al. Adv. Mater. 23, 1545 (2011).

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O-C2-02-02

Molecular strategies toward original nanomaterials: bridging the gap between soft chemistry and solid state chemistry

David Portehault,1,2,3 C. Sanchez1,2,3

1 Sorbonne Universités, UPMC Univ Paris 06, UMR 7574, Chimie de la Matière Condensée de Paris, F-75005, Paris, France.

2 CNRS, UMR 7574, Chimie de la Matière Condensée de Paris, F-75005, Paris, France. 3 Collège de France, Chimie de la Matière Condensée de Paris, 11 place Marcelin Berthelot, 75231

Paris Cedex 05, France.

Reactions between molecule-scale species are often the most suitable for the cost effective fabrication of materials with controlled crystal structure, nano-, meso- and micro-structures. While such chemical pathways are intensively studied since three decades for nanostructured metals, chalcogenides and oxides of metals with high oxidation state, many other compounds families were only scarcely, if ever, reported at the nanoscale. These systems show at the bulk scale mechanical, catalytic, optical and elec-tronic properties without equivalent among common compounds. The design of corresponding nano-structures could therefore lead to important changes or enhancement of existing properties, emergence of new behaviours and novel processing possibilities. This presentation will highlight some of the out-comes of research efforts conducted since few years, aiming at the design of functional nanomaterials with innovative elemental compositions, some of them being considered as “exotic” to chemist. Differ-ent cases will be discussed in this presentation, including reduced titanium oxides, so-called Magnéli phases, metal-boron alloys and boron-carbon-nitrogen covalent frameworks.

1. Maneeratana, V., Portehault, D., Chaste, J., Mailly, D., Antonietti, M. & Sanchez, C. Original electrospun core-shell nanostructured Magnéli titanium oxide fibers and their electrical properties. Adv. Mater. 26, 2654-2658 (2014).

2. Carenco, S., Portehault, D., Boissière, C., Mézailles, N., & Sanchez, C. Nanoscaled Metal Borides and Phosphides: Recent Developments and Perspectives. Chem. Rev. 113, 7981–8065 (2013).

3. Lei, W., Portehault, D., Liu, D., Qin, S. & Chen, Y. Porous boron nitride nanosheets for effective water cleaning. Nat. Commun. 4, 1777-1783 (2013).

4. Lei, W., Portehault, D., Dimova, R. & Antonietti, M. Boron carbon nitride nanostructures from salt melts: tunable water-soluble phosphors. J. Am. Chem. Soc. 133, 7121–7127 (2011).

5. Portehault, D., Devi, S., Beaunier, P., Gervais, C., Giordano, C., Sanchez, C. & Antonietti, M. A General Solution Route toward Metal Boride Nanocrystals. Angew. Chem. Int. Ed. 50, 3262–3265 (2011).

6. Portehault, D., Maneeratana, V., Candolfi, C., Oeschler, N., Veremchuk, I., Grin, Y., Sanchez, C. & Antonietti, M. Facile General Route toward Tunable Magnéli Nanostructures and their Use as Thermoelectric Metal Oxide / Carbon Nanocomposites. ACS Nano 5, 9052–9061 (2011).

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O-C2-03-01

Controlled functionalization of surfaces towards well-defined heterogeneous catalysts and beyond

Prof. Christophe Copéret

ETH Zürich, Department of Chemistry and Applied Biosciences Wolfgang Pauli Strasse, 10 CH-8093 Zürich, Switzerland

[email protected]

Homogeneous and heterogeneous catalysts have, each, specific advantages. While homogeneous catalysts are typically associated with efficient chemical transformations at low temperatures (high selectivity), heterogeneous ones are typically preferred in term of processes (easier regeneration and separation processes).

Here, we will show how it is possible to combine the advantages of homogeneous and heterogeneous catalysts by the controlled functionalization of the surfaces of oxide materials and by the characterization of surface species at the molecular level, thus allowing more predictive approaches.

We will illustrate the power of this approach with the development of well-defined “single-sites”, whose performance and stability can be far above those displayed by homogeneous and heterogeneous catalysts, e.g. alkene metathesis. We will also how this approach can be used to understand industrial catalysts, e.g. Re2O7/Al2O7 and CrO3/SiO2.

With our current level of understanding of surfaces, we will also discuss new directions in this field: understanding defect sites of surfaces and metal-support interactions at the molecular level, introducing diversity in oxide chemistry, controlling the growth of nanoparticles, the development of Surface Enhanced NMR spectroscopy and the potential of this approach in imaging technologies.

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O-C3-01-01

The Quantum Design of Photosynthesis

Rienk van Grondelle

VU University, Amsterdam, The Netherlands

Photosynthesis has found an ultrafast and highly efficient way of converting the energy of the sun into electrochemical energy. The solar energy is collected by Light-Harvesting complexes (LHC) and then transferred to the Reaction Center (RC) where the excitation energy is converted into a charge separated state with almost 100% efficiency. That separation of charges creates an electrochemical gradient across the photosynthetic membrane which ultimately powers the photosynthetic organism. The understanding of the molecular mechanisms of light harvesting and charge separation will provide a template for the design of efficient artificial solar energy conversion systems.

Upon excitation of the photosynthetic system the energy is delocalized over several cofactors creating collective excited states (excitons) that provide efficient and ultrafast paths energy transfer using the principles of quantum mechanics. In the reaction center the excitons become mixed with charge transfer (CT) character (exciton-CT states), which provide ultrafast channels for charge transfer. However, both the LHC and the RC have to cope with a counter effect: disorder. The slow protein motions (static disorder) produce slightly different conformations which, in turn, modulate the energy of the exciton-CT states. In this scenario, in some of the LHC/RC complexes within the sample ensemble the energy could be trapped in some unproductive states leading to unacceptable energy losses.

Here I will show that LHCs and RCs have found a unique solution for overcoming this barrier: they use the principles of quantum mechanics to probe many possible pathways at the same time and to select the most efficient one that fits their realization of the disorder. They use electronic coherence for ultrafast energy and electron transfer and have selected specific vibrations to sustain those coherences. In this way photosynthetic energy transfer and charge separation have achieved their amazing efficiency. At the same time these same interactions are used to photoprotect the system against unwanted byproducts of light harvesting and charge separation at high light intensities.

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O-C3-02-01

Mechanical molecule-machines: gears, wheels, motors and nanocars

Christian Joachim

Pico-Lab & Nanoscience Group Centre d’Elaboration des Matériaux et d’Etudes Structurales (CEMES-CNRS)

29, Rue J. Marvig, BP 94347 31055 Toulouse Cedex, France &

International Center for Materials Nano-architectonics (MANA), National Institute for Materials Science (NIMS), 1-1 Namiki, Tsukuba, Ibaraki 305-0044, Japan

Following the bronze Antikythera calculator 200 BC, the B. Pascal wooden calculating clock 1642 AC and the micro-fabricated machineries on a silicon surface at the end of the 1980’s, it is now foreseen to miniaturise mechanical machineries down to the size of a single molecule. Starting from the principle that there is no fundamental physical limitation to miniaturise the size of a mechanical machine down to the size of a molecule (or better that it is possible to enlarge and structure a molecule to be a mol-ecule-machine [1]), we will present our molecular design and experiments starting from the random rotation of a single molecule-wheel [2], the rotation of the molecule-wheel of a double wheel-axle mechanism [3] and the step by step controlled rotation of a single molecule gear 1.2 nm in diameter [4]. More complex molecular machineries will be presented like a rack & pinion mechanism [5] or our first molecule-vehicles [6,7]. To drive molecule-machineries, we are using the mechanical interaction of the tip apex of an STM and more recently inelastic tunnel current effect as exemplify with our step by step control molecule-motor [8]. To interconnect mechanically a molecule-machine to the macroscopic scale, nano-fabrication of solid state nano-gears down to 30 nm in diameter will be presented [9].

References

[1] C. Joachim, J. Phys., Cond. Mat., 18, S1935 (2006).

[2] J.K. Gimsewski, C. Joachim, V. Langlais, H. Tang & J. Johanson, Science, 281, 531 (1998)

[3] L.Grill, G. Rapenne, X. Bouju, C. Joachim & F. Moresco, Nature Nanotech., 2, 95 (2007)

[4] C. Manzano, W.H. Soe, F. Ample, A. Gourdon & C. Joachim, Nature Materials., 8, 576 (2009)

[5] F. Chiaravalloti, A. Gourdon, C. Joachim & F. Moresco, Nature Materials., 6, 30 (2007).

[6] C. Joachim, H. Tang, F. Moresco, G. Rapenne & G. Meyer, Nanotechnology, 13, 330 (2002).

[7] C.Joachim and G. Rapenne, ACS Nano, 7, 11 (2013).

[8] U.G.E. Perera, F. Ample, H. Kersell, Y. Zhang, G. Vives, J. Echeverria, M. Grisolia, G. Rapenne, C. Joachim and S.-W. Hla, Nature Nanotech, 8, 46 (2013).

[9] Deng Jie, C. Troadec, F. Ample & C. Joachim, Nanotechnology, 22, 275307 (2011).

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O-C3-03-01

New Developments in the area of topological insulators

Claudia Felser, B. Yan, L. Müchler, S. Chadov, J. Kübler, HJ Zhang, and SC Zhang Max Planck Institute of Chemical Physics for Solids, Dresden, 01187 and Johannes Gutenberg Uni-

versity, Mainz, 55128, Germany

Topological insulators are a hot topic in condensed matter physics. The excitement in the physics com-munity is comparable with the excitement when a new superconductor is discovered. HgTe and other systems such as Heusler compounds have an s-p-band inversion at the Fermi edge which makes this family suitable for the Quantum Spin Hall effect and topological insulators [1]. A new topological insulators was identified in cerium-filled skutterudite (FS) compounds. We find that two compounds, CeOs4As12 and CeOs4Sb12, are zero gap materials with band inversions between Os-d and Ce-f orbitals. Both compounds are predicted to become topological Kondo insulators at low temperatures, which are Kondo insulators in the bulk but with robust Dirac surface states on the boundary [2]. In the actinide compounds AmN and PuTe a band gap is opened by correlation effects. In a family of semiconductors with the simple NaCl structure band gaps up to 0.4 eV were found [3]. This is not so surprising since the SOC should be large in Actinides. Up to now there are no oxides which were identified to be topo-logical insulators. BaBiO3 is an oxide which shows a band inversion similar to HgTe. The superconduc-tor BaKBiO3 (BKBO) with Tc nearly 30 K emerges as a TI in the electron-doped region, whereas it is a superconductor in the hole-doped region. BBO exhibits a large topological energy gap of 0.7 eV [4]. We will discuss the necessary and sufficient conditions for new TI materials, based in symmetry and bonding arguments [5].

1. S. Chadov, X. Qi, J. Kübler, G. H. Fecher, C. Felser, S.-C. Zhang, Nature Mater. 9, (2010) 541 “Tunable multifunctional topological insulators in ternary Heusler compounds”

2. B. Yan, L. Müchler, X.-L. Qi, S.-C. Zhang, C. Felser, Phys. Rev. B 85 (2012) 165125 “Topological insulators in filled skutterudites”

3. X. Zhang, HJ. Zhang, J. Wang, C. Felser, S.-C. Zhang, Science 335, (2012)1464 “Actinide Topo-logical Insulator Materials with Strong Interaction”

4. Binghai Yan, Martin Jansen, Claudia Felser, A large energy-gap oxide topological insulator based on the superconductor BaBiO3, Nature Phys. (2013) accepted

5. L.Müchler, HJ. Zhang, S. Chadov, B. Yan, F. Casper, J. Kübler, SC. Zhang, C. Felser, Angew. Chem. Int. Ed. 51, (2012) 7221 “Topological Insulators from a Chemist’s Perspective”

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O-C3-04-01

Synergistic delivery of biologically active agents from metal-organic frameworks

Russell E. Morris1School of Chemsitry, University of St Andrews KY16 9ST, United Kingdom


It is quite a paradox that several gases that we normally think of as extremely toxic are in fact vital in mammalian biology (in the right amounts). Nitric oxide (NO) is the most well-known of these gases – the discovery of its activity in the cardiovascular system led to the Nobel Prize for Medicine and an explosion of research in NO biology and chemistry. Recent research has, however, shown that other ‘toxic’ gases also have tremendous potential for use in therapeutic applications. In all cases the toxicity of the gas places great constraints on how the gases can be delivered, especially if any therapies are to be applied outside the clinic. One method of developing suitable therapies is to devise methods by which the gases can be safely stored in porous solids that deliver the gas only when required and only in safe amounts. In this presentation I will explain how we are using both zeolites and metal organic frameworks as adsorbents and storage materials for several gases, including NO, and how we are characterising the materials to understand how the gases adsorb and are released. I will also present some of our applications data, including examples of experiments done on human subjects in a clinical setting, and also how careful control of the chemistry of the material, particularly metal organic frameworks, can lead to very interesting effects that may be utilised to have great control over hoe the gas interacts with the material, and how it can be utilised.

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O-C4-01-01

Power from the Sun: Perovskite Solar Cells

Mohammad Khaja Nazeeruddin*

Laboratory of Photonics and Interfaces, Department of Chemistry and Chemical Engineering, Swiss Federal Institute of Technology, Station 6, CH-1015 Lausanne, Switzerland.

Thin-film photovoltaics, from the original vacuum-based inorganic devices, to the solution-processed techniques have attracted intensive attention for solar energy conversion into electricity. Recently, or-ganic-inorganic hybrid perovskites thin film photovoltaics came to the limelight because of their high efficiency, low cost and the ease to make these materials solution processable.1-2 Using methyl ammo-nium lead iodide (CH3NH3PbI3) perovskite as an absorber layer and spiro-OMeTAD as a hole transport material, power conversion efficiencies (PCE) of over 15% were obtained in both mesoporous and planar heterojunction solar cells.2 Remarkably, however, the cell has an absorbing perovskite layer as thin as only 300 nm; yet it achieves an open circuit voltage as high as 1.1 V. This performance is com-parable to the best single crystal GaAs thin-film solar cell and outperforms all current high-efficiency polycrystalline thin-film solar cells based on chalcogenide absorbers such as Cu(In,Ga)Se2, CdTe, and Cu2ZnSn(Se,S)4. In this talk we present various deposition methods for perovskite absorbing layer, and the synthesis and characterization of a low band gap hole transporting materials (HTM). The low band gap hole transporting materials function as a p-type HTM in CH3NH3PbI3 solar cells, and as well a light harvester in the visible and near IR regions to complement perovskite absorption yielding high power conversion efficiency.

(1). Lee, M. M., Teuscher, J., Miyasaka, T., Murakami, T. N. & Snaith, H. J. Science 338, 643−647 (2012).

(2). Burschka, J., Pellet, N., Moon, S-J., Humphry-Baker, R., Gao, P., Nazeeruddin. &

Grätzel, M, Nature 499, 316−319 (2013).

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O-C4-01-02

MOLECULAR PHOTOSYNTHESIS: SUCH STUFF AS DREAMS ARE MADE ON

M. Bonchio

ITM-CNR section of Padova,and Dept. of Chemical Sciences, University of Padova, 35131, Padova, Italy


Natural Photosynthesis has emerged from the adaptive evolution of light-activated molecular machineries, shaped and optimized by the dynamic assembly of proteins, pigments and metal-cofactors. Man-made photosynthetic systems lie far behind the natural paradigm, being largely based on covalent strategies, plagued by unproductive losses and unable to catch up with the up-hill water oxidation hurdle. The functional core of oxygenic photosynthesis, a unique Mn4O5Ca cluster (PSII-OEC), is in charge of catalytic water oxidation via a multi-redox manifold; evolving through five electronic states within the protein matrix. The synthetic transposition of such catalytic cycle is the expected turning point for artificial photosynthesis. We present herein a bio-inspired approach to photocatalytic water splitting by multi-metal cores, whose coordination sphere is tuned by the ligand set, including polyoxometalates. Our results address the tailored construction of functional interfaces, shaped at the molecular level and evolved to hybrid nano-structures.[1-5].

References

1. F. Paolucci, M. Prato, M. Bonchio et al. Nature Chemistry, 2, 826-831 (2010).

2. A. Sartorel, F. Scandola, S. Campagna, M. Bonchio et al. J. Am. Chem. Soc., 134, 11104-1107 (2012).

3. S. Piccinin, A. Sartorel, G. Aquilanti, A. Goldoni, M. Bonchio, S. Fabris PNAS, 110, 4917-4922 (2013).

4. F. Paolucci, M. Prato, M. Bonchio et al. ACS Nano, 7, 811-817 (2013).

5. G. Modugno, Z. Syrgiannis, A. Bonasera, M. Carraro, G. Giancane, L. Valli, M. Bonchio, M. Prato. Chem. Commun., 50, 4881-4883 (2014).

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O-C4-02-01

HYBRID ENERGY STORAGE. Merging Battery and Supercapacitor Chemistries.

P. Gomez-Romero1,2

1Catalan Institute of Nanoscience and Nanotechnology, ICN2(CSIC-ICN) Campus UAB, ICN2 Building 08193 Bellaterra, Barcelona, Spain

2Consejo Superior de Investigaciones Científicas, SpainPresenting author: [email protected]

We are on the verge of an energy transition that will turn human kind from energy gatherers (i.e. fossil fuels) into energy farmers (i.e. energy vectors. See Fig. 1). Electrochemical energy storage will be key to this transition but is still far from optimal. That is why there is still plenty of room for new and novel types of materials in this trade. Hybrid materials offer opportunities for synergy and improved properties with respect to their components.[1] Among many possible combinations, those formed by electroactive and conducting components are of particular interest for energy storage applications (Figure 2).[2, 3]

Figure 1: Energy Storage Systems and targeted applications. Figure 2: Some possible hybrid material combinations.

In our group we have developed a whole line of work dealing with hybrid electroactive ( from oxides or phosphates[4] to polioxometalate (POM) clusters,[5]) and conductive materials (conducting polymers or carbons) for energy storage applications. As a matter of fact we have prepared hybrids along the three sides of the triangle shown in Figure 2, [4-9] In this conference we will address our own and other groups approaches towards hybridizing energy storage by taking the hybridization concept to a chemical level (rather than circuitry) and will show the possibilities and advantages provided by materials combining the typical capacitive behavior of supercapacitors with the characteristic faradaic activities of batteries.

[1] P. Gomez-Romero Adv.Mater. 2001, 13(3), 163-174.[2] P. Gomez-Romero et al. J. Solid State Electrochem. 2010 14(11), 1939-45[3] Ait Salah, A.; Mauger, A.; Zaghib, K.; Goodenough, J. B.; Ravet, N.; Gauthier, M.; Gendron, F.; Julien, C. M. J. Electrochem. Soc. 2006, 153(9), A1692-A1701.[4] A. Fedorkova et al. Electrochim Acta 2010, 55(3), 943[5] J. Vaillant et al. Progress in Solid State Chemistry, 2006, 34, 147-159.[6] M. Baibarac and P. Gómez-Romero. Journal of Nanoscience and Nanotechnology, 6(2) 2006, 289-302.[7] M. Baibarac, M. Lira-Cantú, J. Oró Solé, N. Casañ-Pastor and P. Gomez-Romero Small 2006, 2(8-9), 1075[8] V. Ruiz, J. Suárez-Guevara, P. Gomez-Romero Electrochemistry Communications 2012, 24, 35-8.[9] J. Suarez-Guevara, V. Ruiz and P. Gomez-Romero J. Mat. Chem A, 2014, 2, 1014-1021.

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O-C4-03-01

Hunting down ecofriendly materials for Li- and Na-ion batteries

Kristina Edström, Daniel Brandell, Fredrik Björefors and Torbjörn Gustafsson Department of Chemistry – Ångström Laboratory, Uppsala University, Box 538, SE-75121 Uppsala, Sweden

Li-ion batteries are a family of different chemistries that can be tuned for the application where it is to be used. Today Li-ion batteries are dominating portable equipment’s such as mobile phones, cameras, and laptops. They are now up-scaled for use in hybrid and electric vehicles (HEVs and EVs). There are even attempts to develop large battery packs for large scale storage to support intermittent renewable electricity production from wind and solar power. If all expectations will be realized there will be a need for many tons of electrode materials to meet the demands with low cost, efficient, safe and environmentally sustainable lithium-based batteries. In this overview we will discuss the possibility to move from cobalt-based cathode materials to iron-based which will be a trade-off between capacity and cost. We will give examples of cycling efficiencies of Li2FeSiO4, LiFeSO4F and LiFePO4 as cathode materials. We will discuss conversion reactions with Fe2O3 as the anode material and how this can compete with graphite used today. One way of handling the need for large amounts of batteries will be to use Na instead of Li. This will decrease the cost, increase the geopolitical security and lead to marginally lower volumetric energy density for the battery. All the above examples are based upon inorganic insertion/intercalation compounds where mining of the starting products is an environmental concern. We will therefore also discuss our most recent project where organic materials from natural products are extracted or synthesized and then electrochemically tested in Li- and Na-ion batteries. Organic-based batteries cannot compete with inorganic-based when it comes to volumetric energy density which means that they are not a realistic option for automotive applications where a small size matters. Instead they can be used for other applications and thus decrease the pressure on the inorganic-based batteries. We will give examples on both anode- and cathode materials built on organic molecules or polymers. All the discussion will include the need and use of in situ and operando methods to study the materials in a situation as realistic as possible. References 1. H.M. Hollmark, et al., PCCP 13 (2011) 20215. 2. K. Lasri, et al., Solid State Ionics 224 (2012) 15. 3. S. Renault, D. Brandell, T. Gustafsson and K. Edström, Chem. Comm., 49 (2013) 1945. 4. M. H. Kjell, et al. J. Power Sources 243 (2013) 290. 5. A. Sobkowiak, et al., Chem. Mater. 25 (2013) 3020. 6. M. Valvo, et al., J. Power Sources 245 (2014) 967. 7. M. Klett, et al., J. Power Sources 257 (2014) 126 8. Stéven Renault, et al., Electrochem. Comm.45 (2014) 52. 9. S. Renault, D. Brandell and K. Edström, Accepted by Chem Sus Chem (2014).

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O-C5-01-01

Molecular association studied by diffusion and electrophoretic NMR methods. Ions, polymers, nanotubes

I. Furó

KTH Royals Institute of Technology, Department of Chemistry, SE-10044, Stolckholm, Sweden Presenting author: [email protected]

Examples are going to be presented for using NMR spectroscopic method for investigating the association of ions and polymers on one hand and polymers and nanotubes on the other hand. In the former case, electrophoretic NMR (see Fig. 1) in combination with diffusion NMR is used to evaluate the charge polymers and other molecules gain by having ions attached to them [1-2]. Some advantages of the method such as sensitivity for weak binding are elucidated. As concerning nanotubes, diffusion NMR can detect both the exchange of the polymers between the nanotube-bound and free states and the dynamics of the bound polymer molecules on the nanotube surface [3-4].

Figure 1: Electrophoretic 1H NMR spectra of bound and free nucleotides and organic counterions in a uranyl solution [2]. The phase shift in the spectra reports about the electrophoretic mobility of the corresponding species in the mixture.

References

1. F. Hallberg, C. F. Weise, P. V. Yushmanov, E. Thyboll Pettersson, P. Stilbs and I. Furó J. Am. Chem. Soc. 130, 7550 (2008).

2.M. Giesecke, Z. Szabó, and I. Furó, Anal. Methods 5 1648 (2013).

3. R. M. F. Fernandes, M. Buzaglo, M. Shtein, I. Pri Bar, O. Regev, E. F. Marques, and I. Furó, J. Phys. Chem. C 118 582 (2014).

4. A. E. Frise, G. Pagès, M. Shtein, I. Pri Bar, O. Regev, and I. Furó, J. Phys. Chem. B 116 2635 (2012).

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O-C5-01-06

Polymer Solar Cells: From Disorder to Stable Nanostructures

Christian Müller

Department of Chemical and Biological Engineering/Polymer Technology, Chalmers University of Technology, 412 96 Göteborg, Sweden

Polymer solar cells attract considerable attention as a potential renewable energy technology. Typical-ly, the light-harvesting active layer is composed of a fine blend of a polymeric electron-donor and an electron-acceptor such as a fullerene derivative. The precise nanostructure of these bulk-heterojunction blends is critical for achieving an optimal photovoltaic performance. However, bulk-heterojunction blends are metastable materials and hence their nanostructure and photovoltaic performance tend to evolve with time. Thus, in particular elevated processing and operating temperatures pose a formidable challenge to the long-term stability of these materials. In the first part of my talk I will discuss the ther-mal stability of bulk-heterojunctions with respect to the glass transition temperature of the blend as well as the nucleation and growth kinetics of fullerene crystals. Then I will introduce two tools based on 1) nucleating agents and 2) fullerene mixtures, which permit to considerably enhance the thermal stability of this promising class of materials.

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O-C5-02-01

BLOCK COPOLYMER MICELLES AS LONG-CIRCULATING VEHICLES FOR HYDROPHOBIC DRUGS

Petar Petrov

Institute of Polymers, Bulgarian Academy of Sciences, Akad. G. Bonchev Str. 103A, 1113 Sofia, Bulgaria


Polymeric micelles are extensively studied for delivery of active compounds that exhibit poor solubility and bioavailability in physiological fluids. The specific core–shell structure of micelles makes possible the incorporation of poorly water-soluble drugs into the inner hydrophobic core, thus improving their stability and bioavailability. The hydrophilic shell plays an important role for the in vivo behavior of the micelles, providing steric stabilization and ability to interact with the cells. Micelles based on the commercially available poly(ethylene oxide)-block-poly(propylene oxide)-block-poly(ethylene oxide) (PEO–PPO–PEO, “Pluronic”) triblock copolymers are among the most extensively studied systems for delivery of hydrophobic anti-cancer drugs. PEO–PPO–PEO micelles are attractive because they combine good resistance of the PEO shell to protein adsorption and cellular adhesion, the ability of the temperature-responsive PPO core to solubilize water-insoluble compounds and the availability of hydroxyl groups to which receptor-specific ligands can be attached. Since PEO–PPO–PEO micelles are in dynamic equilibrium with molecularly dissolved copolymer chains (unimers), they are, however, very sensitive to changes in concentration and temperature, and may dissociate very fast upon injection into the blood stream. This can lead to the undesired release of the loaded drug before the target is reached (e.g. tumor) or the time interval necessary for the specific treatment. The chemical cross-linking of PEO–PPO–PEO micelles is an effective strategy to stabilize them against destructuration and, thus, to prolong their circulation in the body. Alternatively, the so-called frozen polymer micelles are able to maintain their size and morphology upon dilution at very low concentration and from this point of view can be considered as promising long-circulating drug delivery systems.

This presentation will focus on the development of original micellar systems with potential for long-circulating vehicles of hydrophobic anti-cancer drugs. In particular, the evaluation of “Pluronic” micelles, stabilized by UV-induced crosslinking of pentaerythritol tetraacrylatethe within the core, for delivery of paclitaxel via oral or intravenous route will be discussed [1]. Evidence indicating longer circulation of the stabilized Pluronic micelles containing paclitaxel than the commercial “Taxol” in mice will be presented. In addition, physically crosslinked (frozen) micelles, comprising for example hydrophobic poly(n-butyl acrylate) block, of excellent stability upon severe dilution with prolonged drug release profile will be introduced [2].

Acknowledgements

The financial support of the National Science Fund of Bulgaria (B01-25/2012) and European Commission (POLINNOVA) is gratefully acknowledged.

References

1. K. Yoncheva, P. Calleja, M. Agüeros, P. Petrov, I. Miladinova, Ch. Tsvetanov, J. Irache, Int. J. Pharm. 436 (1-2), 258-264 (2012)

2. P. Petrov, K. Yoncheva, P. Mokreva, S. Konstantinov, J. Irache, A.H.E. Müller, Soft Matter 9 (36), 8745-8753 (2013).

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O-C5-03-01

DESIGNING NANOMATERIALS FOR BIOSENSING

Molly M. Stevens1

1Department of Materials, Department of Bioengineering, Institute of Biomedical Engineering, Lon-don, UK

E-mail: [email protected]

This talk will provide an overview of our recent developments in the design of nanomaterials for ul-trasensitive biosensing. Bio-responsive nanomaterials are of growing importance with potential ap-plications including drug delivery, diagnostics and tissue engineering (1). DNA-, protein- or pep-tide-functionalised nanoparticle aggregates are particularly useful systems since triggered changes in their aggregation states may be readily monitored. Our recent simple conceptually novel approaches to real-time monitoring of protease, lipase and kinase enzyme action using modular peptide functionalized gold nanoparticles and quantum dots will be presented (2). Furthermore we have recently developed a new approach to ultrasensitive biosensing through plasmonic nanosensors with inverse sensitivity by means of enzyme-guided crystal growth (3) as well as a “Plasmonic ELISA” for the ultrasensitive de-tection of disease biomarkers with the naked eye (4). We are applying these biosensing approaches and advanced imaging approaches both in high throughput drug screening and to diagnose diseases ranging from cancer to global health applications (5).

References

1. Stevens MM, George JH, Exploring and engineering the cell surface interface., Science, 2005, 310, 1135-1138.

2. Aili D, Mager M, Roche D, Stevens MM, Hybrid Nanoparticle-Liposome Detection of Phospholi-pase Activity., Nano Letters, 2011, 11, 1401-1405

3. Rodriguez-Lorenzo L, de la Rica R, Alvarez-Puebla RA, Liz-Marzan LM, Stevens MM, Plasmonic nanosensors with inverse sensitivity by means of enzyme-guided crystal growth, Nature Materials, 2012, 11, 604-6074. De la Rica R, Stevens MM, Plasmonic ELISA for the ultrasensitive detection of disease biomarkers with the naked eye., Nature Nanotechnology, 2012, 7, 821-824.5. Bertazzo S., Gentleman E., Cloyd K., Chester A., Yacoub M., Stevens M.M, Nano-analytical elec-tron microscopy reveals fundamental insights into human cardiovascular tissue calcification., Nature Materials. 2013. 12: 576-583.

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O-C5-03-04

CONDUCTING POLYMERS AND THEIR APPLICATIONS

Levent TOPPARE

Department of Chemistry, Middle East Technical University, Ankara 06800, Turkey Department of Biotechnology, Middle East Technical University, Ankara 06800, Turkey

Department of Polymer Science and Technology, Middle East Technical University, Ankara 06800, Turkey The Center for Solar Energy Research and Application (GUNAM), Middle East Technical University,

Ankara 06800, Turkey [email protected]

Conducting polymers have attracted considerable attention in many research fields owing to their overwhelming characteristics like ease of processability, ability of conduct electricity, low cost, straight forward preparation techniques. Our research interests are conducting polymer based electrochromic devices, solar cells, organic light emitting diodes and biosensors. The biosensor technology has attracted great interest due to its many important applications. The new developed techniques also have advantages over conventional laboratory based assays. The conventional methods are time consuming, expensive, required well trained personnel and not used for real time measurements. Nevertheless, biosensors are inexpensive, portable with minimized design, easy to handle, selective and sensitive. In our group, a wide variety of biosensors were emerged as conducting polymer based enzyme biosensors. For these purposes, many conducting polymers which have specific groups were designed and synthesized. These polymers were utilized as immobilization matrices for biosensor construction. During immobilization, several modification structures were used in biosensor fabrication to achieve the most effective surface design for target biosensors. By applying constant potential, consumption of oxygen concentration in bulk solution was followed using amperometric technique. Surface features of the biosensors were characterized using several techniques like SEM, XPS, TEM, and Fluorescence Microscopy. Also, kinetic parameters, operational and storage stabilities were determined. Then, the fabricated biosensors were tested for the detection of target analytes. The result of the biosensor agreed very well with reference methods

Scheme 1. Schematic representation of a biosensor.

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O-D1-01-01

DEFECTS AND MODIFICATIONS OF METAL OXIDE CENTERS AS SOURCE OF THEIR CATALYTIC, PHOTOCATALYTIC AND SENSING

FUNCTIONALITIES

F.Morazzoni 1 , M.D’Arienzo 1, B.Di Credico1, R.Scotti1

Department of Material Science, University of Milano- Bicocca, Via Cozzi 53, 20125, Milano Italy presenting author: [email protected]

Metal oxides play a fundamental role as functional materials acting as catalysts, photocatalysts and resistive sensors. The improving of their functionality goes through the identification of the active centers and of their electronic structure. Several investigation have been performed in this direction, by using in situ and ex situ spectroscopies. In this context the EPR spectroscopy allowed either to perform in situ analyses or to understand electronic properties otherwise difficult to be investigated. Our description will refer to the paramagnetic centers active in the catalytic activation of small molecules (CO, O2, H2) at the surface of pure and transition metal doped oxides, to the electron-hole pairs stable in TiO2 under UV irradiation [1], to the centers responsible for the resistivity changes in semiconductor oxides for gas sensors [2]. The paramagnetic centers are indicative of the operando electronic modifications, and were paramagnetic superoxo derivatives, paramagnetic carbonyl derivatives, paramagnetic singly ionized oxygen vacancies, paramagnetic transition metal centers with different electronic configurations relatable to the operando process. A significant example is the sensing behavior of SnO2 nanocrystals of different shape [3] studied in order to evaluate the role of their exposed crystal surfaces in the sensing mechanism. Octahedral (OCT) , elongated dodecahedral (DOD) , and nanobar shaped (NBA) nanocrystals were synthesized and their sensitivity toward carbon monoxide was evaluated. Singly ionized oxygen vacancies (VO

•) were detected by ESR, and their abundance and reactivity were related to the exposed crystal faces and, in turn, to the sensing responses of the nanocrystals.

Figure 1: Correlation among shape, sensing and oxygen defects

References

1. F.Morazzoni et al. J. of the Am.Chem.Soc. 133(44), 17652-17661 (2011)

2. F.Morazzoni et al. Chemistry of Materials 22(13), 4083-4089 (2010)

3. F.Morazzoni et al. Chemistry of Materials , 25(18), 3675-3686 (2013)

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O-D1-02-01

2-C-METHYL-D-ERYTHRITOL. PRODUCED IN PLANTS,FORMS AEROSOLS IN THE ATMOSPHERE,

A NEW PATHWAY TO ISOPRENOIDS

Thorleif Anthonsen and Elisabeth Egholm Jacobsen1

1Department of Chemistry Norwegian University of Science and Technology

7491 Trondheim, Norway Presenting author: [email protected]

2-C-Methyltetritols, which excist as four stereoisomers, (Fig. 1) are found to be present in the atmosphere above the Amazonian rainforest. It is claimed that these compounds are produced from isoprene by radical oxidation. They are claimed to be secondary organic aerosols (SOA) and as such, they influence the climate directly, through the scattering and absorbtion of sunlight, and indirectly, by functioning as seeds for cloud formation.[1] More recently, detailed analysis has shown that the mixture of stereoisomers from forests in both Brazil and Sweden contains unequal amounts of enantiomers. This shows that the oxidation must be due to enzymatic activity in plants and trees.[2]

Figure 1: Fischer formulas for the four stereoisomers of the 2-C-methyltetritols.

A review of the history of these compounds, synthesis and the significance of stereochemistry is given. Moreover, the significance of 2-C-methyl-D-erythritol for the non-mevalonate route to isoprenoids is briefly discussed.

References

1. M. Claeys, B. Graham, G. Vas, W. Wang, R. Vermeylen, V. Pashynska, J. Cafmeyer, P. Guyon, M. O. Andrae, P. Artaxo, W. Maenhaut, Science 2004, 303, 1173-1176.

2. B. Nozière, N. l. J. D. González, A.-K. Borg-Karlson, Y. Pei, J. P. Redeby, R. Krejci, J. Dommen, A. S. H. Prevot, T. Anthonsen, Geophys. Res. Lett. 2011, 38, L11807-L11811.

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O-D1-03-01

THE ROLE OF PALLADIUM COMPLEXES OF THE TYPE [IL]2[PdX4] IN C-C COUPLING REACTIONS

Anna M. Trzeciak, Ewelina Silarska

Faculty of Chemistry, University of Wrocław, 14 F. Joliot-Curie St., 50-383 Wrocław, Poland Presenting author: [email protected]

Complexes of the type [IL]2[PdX4] (IL = imidazolium or pyridinium cation; X = Cl, Br) can be easily prepared in reaction of PdCl2 with any ionic liquid, [IL]X. Practically unlimited availability of [IL]X allows to obtain a large group of new [IL]2[PdX4] complexes possessing different properties, in particular different bulkiness of IL cation. Under catalytic reaction conditions the IL cation can undergo deprotonation forming N-heterocyclic carbene (NHC), a potential ligand for palladium. Thus, application of [IL]2[PdX4] precursors can result in formation of (NHC)2PdX2 complexes, known as very active catalysts of C-C cross-coupling reactions. Alternatively, during catalytic process, [IL]2[PdX4] precursors can be transformed to Pd(0) nanoparticles stabilized by recovered [IL]X.

[IL]2[PdX4] complexes were used as catalysts of methoxycarbonylation of iodobenzene in ionic liquid media. These studies allowed to discover an inhibiting effect of imidazolium halides, such as [bmim]X, on the reaction course.

I

+[IL]2[PdX4]

CO + MeOH

C

O

OMe

Figure 1. Methoxycarbonylation reaction.

In Suzuki-Miyaura reactions [IL]2[PdX4] complexes shown good catalytic activity already at 40oC. Applicability of these catalysts in Suzuki-Miyaura cross-coupling of different substrates was shown under conventional and MW (microwaves) heating. Combination of ESI-MS, TEM and XRD methods enabled to propose the catalytic reaction pathway with participation of soluble palladium species and Pd(0) nanoparticles. Accordingly, soluble palladium forms are catalytically active, while Pd(0) nanoparticles formed during catalytic reaction represent mainly the resting state of the catalyst and a source of soluble palladium species.

CH3

B(OH)2

CH3

Br

+[IL]2[PdX4]

Figure 2. Suzuki-Miyaura reaction.

References

1. W Zawartka, A.M. Trzeciak, J.J. Ziółkowski, T. Lis, Z. Ciunik, J. Pernak, Adv. Synth. Catal. 348, 1689 (2006)2. E. Silarska, A.M. Trzeciak, J. Pernak, A. Skrzypczak, Appl. Catal. A: Gen., 466, 216 (2013)3. W. Zawartka, A. Gniewek, A.M. Trzeciak, J.J. Ziółkowski, J. Pernak, J. Mol. Catal. A: Chem. 304, 8 (2009)

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O-D1-03-04

Chemisorption and catalytic reactivity on nanometer size clusters:what do we learn from DFT ?

P. Sautet

University of Lyon and CNRS, ENS Lyon, 46 Allée d’Italie, 69364 Lyon, France Presenting author: [email protected]

Heterogeneous catalysis is today at the core of sustainable chemistry, since it allows a fine control of chemical bond forming and breaking processes. This opens energy efficient or selective chemical processes. For the optimal design of catalysts, a fundamental atomic scale understanding of the structure and electronic structure of the catalytic particle, in interaction with the support and with the reactant is of utmost importance. A second complementary key aspect concerns the molecular reaction mechanisms at the active site. Computational chemistry is today a key method, among other physical chemistry characterisation tools to reach such an understanding at the molecular level of the structure of the active site and of the elementary processes occurring during the catalytic act.

By using density functional theory (DFT), we investigate the structure, adsorption properties and reactivity of nanometer size clusters, free or deposited on relevant -alumina surfaces exhibiting various hydroxylation states [1]. Different sizes are considered, from 13 to 201 atoms. The smaller size is at the lower limit of the catalytic objects that can be created and characterized experimentally and presents a strong interest for reforming reactions. On the larger clusters, trends in adsorption as a function of the site on the free cluster is followed, with H and O containing adsorbates. A new generalized coordination number is proposed as a leading descriptor for the adsorption strength.

High coverage is considered on the Pt13 particle, submitted to a pressure of hydrogen or CO, and the equilibrium coverage and shape of the cluster is explored from ab initio thermodynamics. Pt13 particle on alumina show a much stronger adsorption of hydrogen compared to extended surface hence leading to high H coverage (up to 3 H/Pt) and to the formation of a surface hydride [2]. Hydrogen uptake is associated with a change of the shape of the cluster and a weakening of the cluster/support interaction. The thermodynamic stability of various CxHy intermediates from reaction of ethane is explored for various pressure ratio J = P(H2)/P(C2H6), corresponding to different H coverage on the particle. A strong impact of operating conditions is shown on the free energy profile and on the relative stabilities of C1 and C2 intermediates [3].

DFT calculations hence allow the understanding of the stability, structure and chemical reactivity of small Pt particles deposited on alumina as a function of reaction conditions. Simple descriptors as generalized coordination show a strong predictive potential.

References

1. C. Mager-Maury, G. Bonnard, C. Chizallet, P. Sautet and P. Raybaud, ACS Catalysis 2, 1346 (2012).

2. C. Mager-Maury, G. Bonnard, C. Chizallet, P. Sautet and P. Raybaud, ChemCatChem 3, 200 (2011).

3. P. Raybaud, C. Chizallet, C. Mager-Maury, M. Digne, H. Toulhoat, P. Sautet, J. Catal. 308, 328 (2013).

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O-D1-04-01

ANSA-AMINOBORANES: METAL-FREE HYDROGEN ACTIVATION AND HYDROGENATION

Kostiantyn Chernichenko, Victor Sumerin, Markus Lindqvist, Martin Nieger and Timo Repo

Department of Chemistry, University of Helsinki, P.O. Box 55, FIN-00014 Helsinki, Finland.


Recently, a new approach to activate small molecules known as the frustrated Lewis pairs (FLPs) concept has been introduced. In general, FLPs are based on a sterically hindered Lewis acid and a Lewis base which cannot interact and form the Lewis adduct. They are, therefore, highly reactive and even capable of heterolysis of dihydrogen and thus generate onium (for example, phosphonium, ammonium) borohydrides.1,2 This property has led to their use in hydrogenation reactions of polarized multiple bonds.

Ansa-aminoboranes are a class of compounds that hold a Lewis acid and a Lewis base functionalities in the same molecule and wherein formation of the Lewis adducts is structurally prevented.3,4 Holding a FLP like reactivity, ansa-aminoboranes are promising catalysts for heterolytic splitting of dihydrogen and for further development of catalytic applications. The amine, borane and bridging moiety of the ansa-aminoboranes can be greatly varied giving rise to structures with reversible hydrogen activation and advanced catalytic properties including high reactivity in hydrogenation of imines and enamines. In the series of ansa-aminoboranes, 2-[bis(pentafluorophenyl)boryl]-N,N-dimethylaniline (BN cat) is unique and catalyzes facile, metal-free hydrogenation of alkynes to cis-alkenes under mild conditions.5 During hydrogenation the catalyst makes use of several elementary steps including hydroboration and heterolytic hydrogen splitting. Mechanistic aspects both in hydrogen activation and hydrogenation with ansa-aminoboranes will be also discussed.

R2

R1

BN cat

2 bar H2

R2

R1

H

H N

BC6F5

C6F5

BN cat

=

Figure 1: A frustrated-Lewis-pair approach to catalytic reduction of alkynes to cis-alkenes.5

References

1. For review, see D. W. Stephan et al., Angew. Chem., Int. Ed., 49, 46, (2010).

2. V. Sumerin et al., Angew. Chem., Int. Ed., 47, 6001 (2008).

3. V. Sumerin et al., J. Am. Chem. Soc., 130, 14117 (2008).

4. K. Chernichenko, et al., Dalton trans., 41, 9029 (2012)

5. K. Chernichenko, et al., Nat. Chem., 5, 718-723 (2013).

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O-D1-05-01

METALLIC NANOCATALYSTS AND GLYCEROL: A SUSTAINABLE ASSOCIATION

Montserrat Gómez

Laboratoire Hétérochimie Fondamentale et Appliquée, Université de Toulouse 3 – Paul Sabatier, UMR CNRS 5069, 31062, Toulouse, France

[email protected]

Metallic nanoparticles (MNP), including metallic oxides, have generated a huge interest due to their size and electronic configuration leading to attractive properties for different applications, in particular in catalysis.[1] MNP have been largely used in heterogeneous catalysis, giving rise to important industrial applications, mainly in oil refining. More recently, a new facet has appeared, “nanocatalysis”, combining colloidal catalysis (catalysis in solution promoted by nanoparticles) and engineering of nano-objects, displaying specific shapes and/or accommodating stabilisers able to modify the pathway and selectivity of organic transformations.[1] The nature of ligands and solvents involved in the catalytic process plays a central role to preserve the nanometric species. Glycerol represents an innovative solvent coming from the biomass and produced as a waste in the biodiesel manufacture. Its low-cost, non-toxicity, high boiling point, negligible vapour pressure, high solubilizing ability and low miscibility with other organic solvents, constitute key properties to be applied in catalysis.[2] Some works have appeared in the last years concerning the synthesis of MNP in glycerol following the polyol approach, where glycerol acts also as reductant.[3] However only our current works concerning the synthesis of MNP in neat glycerol under base-free conditions have been reported.[4] In this contribution, we will present the synthesis of PdNP and Cu2ONP, their full characterisation and catalytic efficiency in different type of processes, mainly those involving one pot multi-step transformations. The worthy catalyst immobilisation allows the glycerol phase recycling and synthesis of metal-free compounds.

References1. a) Nanoparticles. From theory to application (Ed. G. Schmid), Wiley-VCH, Weinheim, 2004; b) Nanomaterials in catalysis (Eds. K. Philippot, P. Serp), Wiley-VCH Verlag GmbH & Co KGaA, Weinheim, 20132. a) Y. Gu, F. Jérôme, Green Chem. 2010, 12, 1127-1138; b) A. E. Díaz-Alvarez, J. Francos, B. Lastra-Barreira, P. Crochet, V. Cadierno, Chem. Commun. 2011, 47, 6208-6227.3. F. Chahdoura, I. Favier, M. Gómez, Chem. Eur. J. 2014 submitted.4. a) F. Chahdoura, C. Pradel, M. Gómez, Adv. Synth. Catal. 2013, 355, 3648-3660; b) F. Chahdoura, C. Pradel, M. Gómez, ChemCatChem 2014 accepted.

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O-D2-01-01

Exploitation of f-block arene binding for C-H and C-C bond chemistry

Polly L. Arnold,*a Stephen M. Mansell,a Jamie McKinven,a Johann Hlina,a Alessandro Prescimone,a Simon Parsons,a Rebecca C. White,a Rami Batrice,b Maurice Eisen,b Nikolas Kaltsoyannisc and

Michael G. Gardiner.d

aEaStCHEM School of Chemistry, University of Edinburgh, The King’s Buildings, EH9 3JJ, UK. bSchulich Faculty of Chemistry, Israel Institute of Technology, Technion, 32000 Haifa, Israel. cDept. of Chemistry, University College London, 20 Gordon Street, London WC1H 0AJ, UK.

dSchool of Chemistry, University of Tasmania, Private Bag 75, Hobart, Australia. Presenting author: [email protected]

Organometallic f-block compounds have shown many interesting small molecule activation reactions, including hydrocarbon C-H bond cleavage, and the study of interactions of f-block cations with soft hydrocarbon and arene ligands provides important contributions to the understanding of covalency in f-element ligand bonding that is needed for nuclear waste handling.

We will present new f-block complexes with simple ligands that bind and reduce arenes spontaneously, even at room temperature, forming inverse arene sandwich complexes. The arenes are sufficiently activated, and the conditions sufficiently mild, that a regioselective C-H bond functionalisation with boranes is possible. This has allowed studies of the catalytic capabilities of these complexes, and the first f-element catalysed catalytic alkyne cyclotrimerisation reactions. Details of the mechanism, requirements for the ancillary ligands, and C-H bonding interactions with the metal centre will be shown.

One of the factors that drives the chemistry is the favourability of δ-symmetry bonding interactions with the π-system. We will show new chemistry of a macrocyclic ligand (meso-octamethyl-trans-calix[2]benzene[2]pyrrolide) that exploits this feature in the formation of new bis(arene)sandwich-like geometries, as well as forming complexes with close metal-metal distances.

C-H borylation

spontaneous arene activation alkyne cyclotrimerisationXU

X

XX

UX

X

X2U UX2

BR2R

X = bulky, monoanionic group

[U]

R

R

R

[U]

UIII2X4(L)

N

N

UX

XU

X

X

M-M interactions

Figure1

References

1. P. L. Arnold, S. M. Mansell, D. McKay, and L. Maron, Nature Chem., 2012 , 4, 668.2. S. M. Mansell, J. H. Farnaby, A. I. Germeroth, P. L. Arnold, Organometallics, 2013 , 32, 4214.3. P. L. Arnold, J. H. Farnaby, R. C. White, N. Kaltsoyannis, M. G. Gardiner, J. B. Love, Chem.

Sci. 2014 , 5, 756; P. L. Arnold, C. J. Stephens, J. H. Farnaby, M. G. Gardiner, J. B. Love, submitted.4. P. L. Arnold, J. McKinven, R. Batrice, M. Eisen, in preparation.

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O-D2-01-05

Hydrogen Evolution: Bioinspired Catalysts and Artificial Hydrogenases

Vincent Artero

Laboratory of Chemistry and Biology of Metals (Univ. Grenoble Alpes, CNRS and CEA-Grenoble)

Hydrogen production, through the reduction of water in electrolysers, is currently one of the most convenient ways to store energy durably, if the electrical energy is initially obtained from renewable resources. However, while electrolysis is a mature and robust technology, the most promising devices, based on proton exchange membranes, relay on the use of platinum as electrocatalyst to accelerate both hydrogen evolution and water oxidation reactions. However, this rare and expensive metal is not itself a renewable resource, so the viability of a hydrogen economy depends on the design of new efficient and robust electrocatalytic materials based on earth-abundant elements [1]. A competitive alternative to platinum could be found in living micro-organisms metabolizing hydrogen thanks to hydrogenases. Catalysis in hydrogenases only requires base-metal centers (nickel and iron) and we will show how their active sites can be used as an inspiration to design new synthetic catalysts. We found that cobalt diimine–dioxime complexes are efficient and stable electro-catalysts for hydrogen evolution form acid-ic non-aqueous solutions with slightly lower overvoltages [2, 3] and much larger stabilities towards hy-drolysis as compared to previously reported cobaloxime catalysts [4, 5]. We will report on our approach for the covalent functionalization of electrode materials with such catalysts and their activity under fully aqueous conditions [6]. Integration of cobalt-based catalysts into protein frameworks to prepare artificial hydrogenases and their combination with photosensitizers to design photocatalytic systems able to achieve the photochemical production of hydrogen will also be discussed [7-9].

References 1. V. Artero, M. Chavarot-Kerlidou and M. Fontecave, Angew. Chem. Int. Ed., 50 (2011) 7238.2. P.-A. Jacques, V. Artero, J. Pécaut and M. Fontecave, Proc. Natl. Acad. Sci. U.S.A., 106 (2009) 20627.3. A. Bhattacharjee, E.S. Andreiadis, M. Chavarot-Kerlidou, M. Fontecave, M.J. Field and V. Artero, Chemistry – A European Journal, 19 (2013) 15166 4. M. Razavet, V. Artero and M. Fontecave, Inorg. Chem., 44 (2005) 4786.5. C. Baffert, V. Artero and M. Fontecave, Inorg. Chem., 46 (2007) 1817.6. E.S. Andreiadis, P.-A. Jacques, P.D. Tran, A. Leyris, M. Chavarot-Kerlidou, B. Jousselme, M. Matheron, J. Pécaut, S. Palacin, M. Fontecave and V. Artero, Nat. Chem., 5 (2013) 48.7. A. Fihri, V. Artero, A. Pereira and M. Fontecave, Dalton Trans., (2008) 5567.8. A. Fihri, V. Artero, M. Razavet, C. Baffert, W. Leibl and M. Fontecave, Angew. Chem. Int. Ed., 47 (2008) 564.9. P. Zhang, P.-A. Jacques, M. Chavarot-Kerlidou, M. Wang, L. Sun, M. Fontecave and V. Artero, In-org. Chem., 51 (2012) 2115.

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O-D2-02-01

New Catalytic Reactions with Carbene-Radicals

Bas de Bruin

Homogeneous and Supramolecular Catalysis Group, van ’t Hoff Institute for Molecular Chemistry (HIMS), University of Amsterdam, Science Park 904, 1098 XH Amsterdam. E-mail: [email protected]

Radicals are intrinsically reactive, and typically difficult to control. However, in the coordination sphere of transition metals highly selective radical-type processes are certainly possible. In fact, radical-type reactions are tremendously important in several bio-synthetic pathways mediated by metallo-enzymes. Nature solves its most difficult and most interesting bio-synthetic problems with radical-reactivity, yet with ultrahigh precision and selectivity. Inspired by such catalytic radical-type transformations mediated by metallo-enzymes, we recently started to investigate new catalytic radical-type transformations with synthetic catalysts.1

We found that discrete ‘carbene radicals’ are readily formed upon reaction of cobalt porphyrins with diazo-compounds.2 They play a crucial role in a variety of catalytic radical-type transformations, and offer ample opportunities for the development of new reactivity.

In this contribution we disclose new catalytic radical-type reactions mediated by cobalt porphyrin complexes using ‘carbene radical’ reactivity.3 Some of these reactions are performed in a supramolecular cage.4

1. a) V. Lyaskovskyy, B. de Bruin, ACS Catalysis, 2012, 2, 270. d) A. I. Olivos Suarez, V. Lyaskovskyy, J. N. H. Reek, J. I. van der Vlugt, B. de Bruin, Angew. Chem. Int. Ed., 2013, 52, 12510–12529.2. a) W.I. Dzik, X. Xu, X.P. Zhang, J.N. Reek, B. de Bruin, J. Am. Chem. Soc., 2010, 132, 10891. b) V. Lyaskovskyy, A.I. Olivos Suárez, H. Lu, H. Jiang, X.P. Zhang, B. de Bruin, J. Am. Chem. Soc. 2011, 133,12264. c) W.I. Dzik, J.N.H. Reek, B. de Bruin, B., Chem. Eur. J., 2008, 14, 7594. d) W.I. Dzik, X. P. Zhang, B. de Bruin, Inorg. Chem., 2011, 50, 9896.3. N.D. Paul, H. Lu, X. P. Zhang, B. de Bruin, Chem. Eur. J., 2013, 19, 12953.4. M. Otte, P. F. Kuijpers, O. Troeppner, I. Ivanović-Burmazović, J.N.H. Reek, B. de Bruin, B.; Chem. Eur. J., 2013, 19, 10170.

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O-D2-03-01

Stable Silylenes for a New Generation of Steering Ligands in Catalysis

Shenglai Yao,# Burgert Blom, # Miriam Stoelzel, # Daniel Gallego, # Andreas Brueck, #§ John F. Hartwig,§ and Matthias Driess#*

Presenting author: [email protected] #Technische Universität Berlin, Department of Chemistry: Metalorganics and Inorganic Materials,

Sekr. C2; Strasse des 17. Juni 135, D-10623 Berlin, Germany §Department of Chemistry, University of California, Berkeley, USA

Recently, we developed two new types of zwitterionic silylenes 1 and 2 which show an unprecedented reactivity pattern with respect to small molecule activation in comparison to other cyclic silylenes. [1,2] The facile oxygenation of 1 with N2O or CO2 in the presence of donor ligands coordinated to the divalent silicon led to isolable silanone complexes 3 which are also capable for facile activation of small molecules including ammonia, water, and hydrogen sulfide. Furthermore, the remarkable rich reactivity pattern of 1, 2 and the first silicon(II)-based pincer arene ligands 4-6 can be employed as a new generation of steering ligands in homogeneous catalysis. [3-6] In my talk I wish to discuss selected features on the reactivity of 1-5 and in particular their use in catalytic transformations.

Si:N

N

R

R

_

Si:N

N

R

R1: LSi

_

R = 2,6 - iPr2C6H3

SiN

N

R

R

3

O

L

Si:

PR3

PR32

X

O

O

SiL

SiL4

FeSiL

SiL

6

N

N

N

SiL

SiL5

R

R

References/1/ Reviews: M. Assay, M. Driess, C. Jones Chem. Rev. 2011, 111, 354; S. Yao, Y. Xiong, M. Driess Organometallic s 2011, 30, 1748./2/ M. Assay, S. Inoue, M. Driess Angew. Chem. Int. Ed. 2011, 50, 9589./3/ W. Wang, S. Inoue, E. Irran, M. Driess Angew. Chem. Int. Ed. 2012, 51, 3691./4/ W. Wang, S. Inoue, S. Enthaler, M. Driess Angew. Chem. Int. Ed. 2012, 51, 6167./5/ D. Gallego, A. Brück, E. Irran, F. Meier, M. Kaupp, M. Driess, J. F. Hartwig J. Am. Chem. Soc., 2013, 135,15617/6/ Review on NHSi complexes in catalysis: B. Blom, D. Gallego, M. Driess Inorg. Chem. Front., 2014,1, 134.

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O-D2-04-01

Peptides as scaffolds for the controlled formation of metal nanoparticles

Helma Wennemers

Laboratory of Organic Chemistry, ETH Zurich, 8093 Zurich, Switzerland [email protected]

Silver nanoparticles offer great opportunities for applications in, for example, molecular electronics, catalysis, imaging and as antimicrobial coatings. Their properties strongly depend on their size and shape that are difficult to control. For the controlled formation of stable AgNPs, additives such as polymers and surfactants are typically used. However, little is known about the correlation between the molecular structure of the additive and the resulting nanoparticle.

Our group explores the use of peptides as additives for the generation of silver and other metal nanoparticles. We envision that the large structural and functional diversity of different peptides might allow for the formation of tailor-made nanoparticles. In addition, we aim at a deeper understanding of how the molecular factors of the additive control nanoparticle formation. Towards these goals we use combinatorial split-and-mix libraries and functionalized oligoprolines as rigid scaffolds.

References

1. K. Belser, T. V. Slenters, C. Pfumbidzai, G. Upert, L. Mirolo, K. M. Fromm, H. Wennemers, Angew. Chem. Int. Ed., 2009, 48, 3661.

2. G. Upert, F. Bouillère, H. Wennemers, Angew. Chem. Int. Ed., 2012, 51, 4231.

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O-D4-01-01

Adventures in Natural Products Chemistry: Methodology, Synthesis, Structure Determination

Jonathan W. Burton*

Department of Chemistry, University of Oxford, Chemistry Research Laboratory, Mansfield Road, Oxford, OX1 3TA, United Kingdom

In the first part of the 20th

century, the structure determination of natural products was a laborious task that involved the degradation and derivatization of gram quantities of material to provide structure information, followed by total synthesis for structure confirmation. Nowadays, the structure determination of complex molecules, including natural products, is routinely achieved on milligram quantities of material using high-field NMR experiments and, where applicable, X-ray crystallographic analysis. Despite these powerful techniques, the structure assignment of complex natural products remains challenging and total synthesis still plays a role in structure confirmation and structure determination. More recently, the use of DFT methods to calculate the spectroscopic properties of organic molecules (particularly NMR chemical shifts) has emerged as a powerful additional tool for structure determination.

Recently, we reported the total synthesis of the originally proposed structure of a small halogenated marine natural product isolated from Laurencia species and proposed that the actual structure was a 2,2’-bifuranyl rather than a pyrano[3,2b]pyran.

1 On the basis of a reasonable biogenesis, coupled with

DFT calculations of 13

C NMR chemical shifts (collaboration with Dr Jonathan Goodman (Cambridge) and Dr Robert Paton (Oxford)),

2 we predicted the stereostructure of elatenyne as one out of 32 possible

diastereomers and confirmed this prediction by two independent total syntheses (collaboration with Prof. Deukjoon Kim (SNU)).

3 The power of this combined biogenetic/computational/synthetic approach for

structure determination will be further exemplified with a number of other, structurally related, natural products.

4

Acknowledgement

We thank the Royal Society, the EPSRC, and GlaxoSmithKline for funding.

References 1. Sheldrake, H. M.; Jamieson, C.; Burton, J. W. The changing faces of halogenated marine natural products: Total

synthesis of the reported structures of elatenyne and an enyne from Laurencia majuscula. Angew. Chem. Int. Ed. 2006, 45, 7199-7202.

2. Smith, S. G.; Paton, R. S.; Burton, J. W.; Goodman, J. M. Stereostructure assignment of flexible five-membered rings by GIAO

13C NMR calculations: Prediction of the stereochemistry of elatenyne. J. Org. Chem. 2008, 73, 4053-4062.

3. Dyson, B. S.; Burton, J. W.; Sohn, T. I.; Kim, B.; Bae, H.; Kim, D. Total synthesis and structure confirmation of elatenyne: success of computational methods for NMR prediction with highly flexible diastereomers. J. Am. Chem. Soc. 2012, 134, 11781-11790.

4. Shepherd, D. J.; Broadwith, P. A.; Dyson, B. S; Paton, R. S; Burton, J. W. Structure Reassignment of Laurefurenynes A and B by Computation and Total Synthesis. Chem. Eur. J., 2013, 19, 12644-12648.

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O-D4-02-01

New Horizons of Gold Catalysis

A. S. K. Hashmi1

1Organisch-Chemisches Institut, Universität Heidelberg, Im Neuenheimer Feld 270, 69120 Heidelberg, Germany


Homogeneous catalysis by gold has emerged to an important sector of catalysis research [1]. In the first years, initiated by two milestone publications from the year 2000 [2,3], the efforts in methodology development clearly dominated, in the more recent past also an increasing number of applications in synthesis has been reported [4,5]. All the time efforts to understand the basic mechanism of these reactions accompanied the field [6].

For twelve years most of the reactions followed simple reaction mechanisms, basing on the interaction of one single gold centre in a gold complex or organogold compound with the substrate molecule. In most of these reactions vinylgold [7] or alkylgold intermediates are involved, sometimes also gold carbenoids.

Now an entirely new family of reactions, basing on the activation of the organic substrates by two gold complexes at the same time (one s-coordinated, the other p-coordinated), has been discovered [8]. These open up entirely new synthetic possibilities and follow quite complex, new mechanisms. The different mechanistic possibilities will be discussed in detail.

Some of these new reactions even allow positional selective C,H activations of alkyl side chains, as exemplified below, allowing to use simple alkyl side-chains for anellation processes.

S

TDAC PF6

2.5 %

DCE65oC

R1

R3

R2S

R1

R3

R2NHCAu

AuNHC

NHC =

N

N

iPr

iPr

iPr

iPr+TDAC =

Figure 1: Anellated thiophenes by C,H activation applying a traceless dual activation catalyst (TDAC)

The presentation will also contain results from computational chemistry.

References1. A. S. K. Hashmi, Chem. Rev. 107, 3180-3211 (2007). 2. A. S. K. Hashmi, L. Schwarz, J.-H. Choi, T. M. Frost, Angew. Chem. Int. Ed. Engl. 39, 2285-2288 (2000).3. A. S. K. Hashmi, T. M. Frost, J. W. Bats, J. Am. Chem. Soc. 122, 11553-11554 (2000).4. A. S. K. Hashmi, M. Rudolph, Chem. Soc. Rev. 37, 1766-1775 (2008).5. M. Rudolph, A. S. K. Hashmi, Chem. Soc. Rev. 41, 2448-2462 (2012).6. A. S. K. Hashmi, Angew. Chem. Int. Ed. 49, 5232-5241 (2010).7. A. S. K. Hashmi, A. Schuster, F. Rominger, Angew. Chem. Int. Ed. 48, 8247-8249 (2009).8. A. S. K. Hashmi, I. Braun, M. Rudolph, F. Rominger, Organometallics 31, 644–661 (2012).

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O-D4-02-06

Efficient Transition Metal Catalysis with Multi-Chamber Reactors

Troels Skrydstrup*

Interdisciplinary Nanoscience Center (iNANO), Department of Chemistry, Aarhus University

Gustav Wieds Vej 14, 8000 Aarhus, Denmark [email protected]

In this talk, I will present our latest work dealing with transition metal catalyzed carbonylation reactions aimed at the development of new techniques and new synthetic transformations using carbon monoxide. In particular, I will focus my presentation on the use of carbon monoxide releasing molecules (CORMs) in combination with a recently designed two-chamber reactor, which provides a convenient and simple set-up for performing carbonylation reactions without having to consider the hazards associated with this toxic diatomic molecule. The talk will also cover various aspects including carbonylation reactions employing stoichiometric and substoichiometric carbon monoxide, the development of new carbonyla-tion transformations, as well as new methods for isotope labeling. Furthermore, I will present on going work with other small molecular weight gases, including carbon dioxide, ethylene and hydrogen.

Relevant references1. Hermange, P.; Lindhardt, A. T.; Taaning, R. H.; Bjerglund, K.; Lupp, D.; Skrydstrup, T. J. Am. Chem. Soc. 2011, 133, 6061. 2. Friis, S. D.; Taaning, R. H.; Lindhardt, A. T.; Skrydstrup, T. J. Am. Chem. Soc. 2011, 133, 18114. 3. Gøgsig, T. M.; Taaning, R. H.; Lindhardt, A. T.; Skrydstrup, T. Angew. Chem. Int. Ed. 2012, 51, 798. 4. Korsager, S.; Taaning, R. H.; Skrydstrup, T. J. Am. Chem. Soc. 2013, 135, 2891. 5. Korsager, S.; Taaning, R. H.; Skrydstrup, T. Angew. Chem. Int. Ed. 2013, 52, 9763.6. Lescot, C.; Nielsen, D. U.; Marakov, I.; Lindhardt, A. T.; Daasbjerg, K.; Skrydstrup, T. J. Am. Chem. Soc. 2014, 136, 6142.7. Lian, Z.; Friis, S.; Skrydstrup, T. Angew. Chem. Int. Ed. 2014, DOI: 10.1002/anie.201404217R1.

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O-D4-03-01

Metal-Catalyzed Cross-Coupling Reactions

Greg Fu

Caltech, USA

Despite the tremendous accomplishments that have been described in the development of transition metal-catalyzed coupling processes, it is nevertheless true that many significant opportunities remain. For example, to date the overwhelming majority of studies have focused on couplings between two sp2-hybridized reaction sites (e.g., an aryl metal with an aryl halide).

As of 2001, there were relatively few examples of metal-catalyzed coupling reactions of alkyl electro-philes. During the past several years, we have pursued the discovery of transition metal-based cata-lysts for coupling activated and unactivated alkyl electrophiles that bear β hydrogens. Our recent ef-forts to develop broadly applicable methods, including enantioselective processes, will be discussed.

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O-D4-04-01

DECIPHERING THE BIOLOGICAL MECHANISMS OF BURULI ULCER THANKS TO TOTAL SYNTHESIS

N. Blanchard

Université de Strasbourg, Laboratoire de Chimie Moléculaire ECPM-CNRS, 25 rue Becquerel, 67087 Strasbourg, France.

E-Mail : [email protected]

Buruli ulcer is a necrotizing skin disease present in more than thirty countries in the world, located mainly in West and Central Africa but also in Australia and now Japan.1 To date no specific and efficient treatment of Buruli ulcer has been developed which correlates with the dramatic lack of understanding of the associated chemical and biological mechanisms. This infection is caused by Mycobacterium ulcerans that secretes a toxin called mycolactone. This macrolide is the first polyketide isolated from a human pathogen. For the past six years, we have been involved in a research program at the frontier of total synthesis and immunology, aiming at better understanding the mode of action of these human toxins.2 We have devised a modular synthetic approach that allowed us to describe one of the first structure-activity relationships of these toxins. Based on this knowledge, structurally related fluorescent hybrids were prepared and used in confocal microscopy. In collaboration with the Pasteur Institute, these informations were crucial to the discovery and confirmation of the first proteic target of mycolatones, a family of actin nucleating factors called WASP (Wiskott-Aldrich Syndrome Protein), a long-standing goal in this research area.

DECIPHERING THE BIOLOGICAL MECHANISMS OF BURULI ULCER THANKS

TO TOTAL SYNTHESIS

N. Blanchard

Université de Strasbourg, Laboratoire de Chimie Moléculaire ECPM-CNRS, 25 rue Becquerel, 67087 Strasbourg, France.

E-Mail : [email protected]

Buruli ulcer is a necrotizing skin disease present in more than thirty countries in the world, located mainly in West and Central Africa but also in Australia and now Japan.1 To date no specific and efficient treatment of Buruli ulcer has been developed which correlates with the dramatic lack of understanding of the associated chemical and biological mechanisms. This infection is caused by Mycobacterium ulcerans that secretes a toxin called mycolactone. This macrolide is the first polyketide isolated from a human pathogen. For the past six years, we have been involved in a research program at the frontier of total synthesis and immunology, aiming at better understanding the mode of action of these human toxins.2 We have devised a modular synthetic approach that allowed us to describe one of the first structure-activity relationships of these toxins. Based on this knowledge, structurally related fluorescent hybrids were prepared and used in confocal microscopy. In collaboration with the Pasteur Institute, these informations were crucial to the discovery and confirmation of the first proteic target of mycolatones, a family of actin nucleating factors called WASP (Wiskott-Aldrich Syndrome Protein), a long-standing goal in this research area.

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Figure 1: Harnessing total synthesis of mycolactone analogues for a better mechanistic understanding of Buruli ulcer pathogenesis.

References 1. A. C. Chany, C. Tresse, V. Casarotto, N. Blanchard, Nat. Prod. Rep. 2013, 30, 1527-1567. 2. (a) C. Demangel, N. Blanchard, G. Bismuth, V. Casarotto, A. C. Chany, Institut Pasteur Assignee, Fr, EP

2011-306521, May 2013; (b) A.-C. Chany, V. Casarotto, M. Schmitt, C. Tarnus, L. Guenin-Macé, C. Demangel, O. Mirguet, J. Eustache, N. Blanchard, Chem. Eur. J. 2011, 17, 14413-14419.

Figure 1: Harnessing total synthesis of mycolactone analogues for a better mechanistic understanding of Buruli ulcer pathogenesis.

References

1. A. C. Chany, C. Tresse, V. Casarotto, N. Blanchard, Nat. Prod. Rep. 2013, 30, 1527-1567.2. (a) C. Demangel, N. Blanchard, G. Bismuth, V. Casarotto, A. C. Chany, Institut Pasteur Assignee,

Fr, EP 2011-306521, May 2013; (b) A.-C. Chany, V. Casarotto, M. Schmitt, C. Tarnus, L. Guenin-Macé, C. Demangel, O. Mirguet, J. Eustache, N. Blanchard, Chem. Eur. J. 2011, 17, 14413-14419.

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O-D4-05-01

Design and Synthesis of new Pyrrole- and Indole-Condensed Heterocycles via Alkyne Cyclization

Metin Balcı

Department of Chemistry, Middle East Technical University 06800 Ankara/Turkey [email protected]

The ability to perform the key bond-forming step which transforms an acyclic precursor into the desired cyclic structure in a regio- and stereocontrolled manner remains critical to the construction of complex molecules. Alkyne cyclization is one of the methodologies forming new heterocycles.1,2 The synthesis of various heterocycles via gold-catalyzed alkyne cyclization and the reaction with substituted hydrazines and/or amines with alkyne will be discussed.3

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References

1. M. Rudolph, A. S. K. Hashmi, Chem. Soc. Rev. 41, 2448 (2012)

2. C. Aubert, L. Fensterbank, P. Garcia, M. Malacria, A. Simonneau, Chem . Rev. 111, 1954 (2011)

3. N. Menges, O. Sarı, Y. Abdullayev, S. S. Erdem, M. Balci, J. Org. Chem. 78, 5184-5195, (2013).

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O-E1D3-01-01

MULTISPECTRAL OPTOACOUSTIC MESOSCOPY FOR IMAGING BIOCHEMISTRY IN-VIVO

Vasilis Ntziachristos

Technische Universität München & Helmholtz Zentrum München Presenting author: [email protected]

Optical imaging is unequivocally the most versatile and widely used visualization modality in the life sciences. Yet it is significantly limited by photon scattering, which complicates imaging beyond a few hundred microns. For the past few years however there has been an emergence of powerful new optical imaging methods that can offer high resolution imaging beyond the penetration limits of microscopic methods. These methods can prove essential in cancer research. Of particular importance is the development of multi-spectral opto-acoustic tomography (MSOT) that brings unprecedented optical imaging performance in visualizing anatomical, physiological and molecular imaging biomarkers. Some of the attractive features of the method are the ability to offer 10-100 microns resolution through several millimetres to centimetres of tissue and real-time imaging. In parallel we have now achieved the clinical translation of targeted fluorescent probes, which opens new ways in the interventional detection of cancer in surgical and endoscopic optical molecular imaging. This talk describes current progress with methods and applications for in-vivo optical and opto-acoustic imaging in cancer and outlines how new opto-acoustic and fluorescence imaging concepts are necessary for accurate and quantitative molecular investigations in tissues.

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O-E1D3-02-01

Gd-based nanosized systems as highly efficient MRI probes

Mauro BottaDipartimento di Scienze e Innovazione Tecnologica, Università del Piemonte Orientale “Amedeo

Avogadro”, Alessandria, Italy

The use of GdIII chelates represents a common approach to alter the intensity of Magnetic Resonance Imaging (MRI) signal thus enhancing the image contrast. However, currently used Gd-based contrast agents possess only fraction of the efficacy (relaxivity, r1) predicted by the theoretical models. The use of macromolecular constructs, including polymers, dendrimers, micelles and liposomes, chemically modified viral capsids and silica nanoparticles is an emerging technology for the development of high relaxivity Gd-based MRI contrast agents.1 These MRI nanoprobes make it possible to deliver to the site of interest a large number of GdIII ions, thus increasing the sensitivity of the technique. These systems possess high molecular relaxivity resulting from both the additive effect of all of the active GdIII centres and the reduced tumbling rate that enhances the r1 of each complex. However, in spite of the high relax-ivities per particle found for these systems, the r1 values for the individual gadolinium centres are typi-cally modest [10-20 mM-1s-1 at 298 K, 0.47 T] and well below theoretical expectations. The two major limiting factors are the use of neutral Gd complexes (DTPA bisamides and DOTA monoamides) exhib-iting slow water exchange (kex = 1/τM) and/or fast local rotation of the GdIII complex around its linker to the nanoparticle. The optimisation of several physico-chemical parameters (hydration number q, water exchange rate and rotation flexibility of the chelate) allows to obtain dramatic relaxivity enhancement (> 200%) of the individual paramagnetic building blocks without compromising their stability. To probe the potential gains in relaxivity that can be achieved through the optimization of the molecular parameters we have prepared and characterized several Gd-based nanosized systems: a) amphiphilic DOTA-like Gd3+ chelates loaded into lipidic nanoparticles and dendrimersomes;2

b) selective anchoring of GdDOTA-like complexes on the external surface of organo-modified meso-porous silica nanoparticles;3 c) GdF3 nanoparticles (< 5 nm) coated with various organic molecules.4

References

1) M. Botta, L. Tei, Eur. J. Inorg. Chem. 2012, 1945-1960

2) F. Kielar, L. Tei, E. Terreno, M. Botta, J. Am. Chem. Soc. 2010, 132, 7836–7837

3) F. Carniato, L. Tei, A. Arrais, L. Marchese, M. Botta, Chem. Eur. J. 2013, 19, 1421–1428

4) F. Carniato, K. Thangavel, L. Tei, M. Botta, J. Mater. Chem. B 2013, 1, 2442–2446

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O-E1D3-02-02

Responsive and multimodal imaging probes based on metal complexes

Éva Tóth

Centre de Biophysique Moléculaire, CNRS, Orléans, France

Metal complexes, including lanthanide chelates, are widely used as imaging probes in various imaging modalities. In Magnetic Resonance Imaging, the increase of the probe efficiency remains an important challenge.1 Emerging applications in molecular imaging seek a real-time, repeatable, in vivo visualization of molecules or molecular events at the cellular and tissue level. One important field in molecular imaging involves the in vivo detection of physico-chemical parameters of tissues, concentration of ions, metabolites, etc. by applying smart, activatable imaging probes that are responsive to the specific parameter to detect.2 In contrast to nuclear imaging modalities, MRI is particularly well adapted to the design of responsive probes, involving Gd3+-based or PARACEST (Paramagnetic Chemical Exchange Saturation Transfer) agents. The efficacy (relaxivity or CEST properties) of the probe has to be selectively influenced, based on coordination chemistry concepts, by the particular biomarker that we wish to detect. We develop potential smart contrast agents to detect cation3 or neurotransmitter concentration changes in the extracellular space or to monitor enzyme activity.4

Recently, bimodal imaging has emerged as a novel concept to ascertain observations made in one imaging modality by a complementary technique. Ideally, bimodal imaging is performed by using bimodal probes that combine the characteristics required for both imaging modalities within a single molecular entity. Our major interest is to use lanthanide chelates as bimodal imaging agents for combined MRI and optical detection. Given the diverse magnetic and optical properties of lanthanide ions, lanthanide complexes are perfectly suited for the design of MRI and optical bimodal probes. Different approaches to develop lanthanide-based bimodal agents will be presented.5

1. The Chemistry of Contrast Agents in Medical Magnetic Resonance Imaging”, 2nd edition, Eds. A. E. Merbach, L. Helm and É. Tóth, John Wiley & Sons, 2013

2. C. S. Bonnet and É. Tóth, Smart magnetic resonance imaging agents relevant to potential neurological applications, American Journal of Neuroradiology, 2010, 31, 401-409.

3. G. Angelovski, T. Chauvin, R. Pohmann, N. K. Logothetis, É. Tóth, Calcium-Responsive Paramagnetic CEST Agents, Bioorganic & Medicinal Chemistry, 2010, 19, 1097

4. T. Chauvin, P. Durand, M. Bernier, H. Meudal, B.-T. Doan, F. Noury, B. Badet, J.-C. Beloeil, É. Tóth, Detection of Enzymatic Activity by PARACEST MRI: A General Approach to Target a Large Variety of Enzymes, Angew. Chem, Int. Ed. 2008, 47, 4370.

5. S. Lacerda, C. S. Bonnet, A. Pallier, S. Villette, F. Foucher, F. Westall, F. Buron, F. Suzenet, C. Pichon, S. Petoud and É. Tóth, Lanthanide-based, near-infrared luminescent and magnetic lipoparticles: monitoring particle integrity, Small, 2013, 9, 2662.

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O-E1D3-03-02

Novel Intramolecular Spirocyclization-Based Fluorogenic Probes: From in Vivo Imaging of Tiny Tumors

to Super-Resolution Imaging

Yasuteru Urano

Graduate School of Pharmaceutical Sciences and Graduate School of Medicine, The University of Tokyo

Basic Research Program, Japan Science and Technology Presenting author: [email protected]

Fluorescence imaging is one of the most powerful techniques currently available for continuous observation of dynamic intracellular processes in living cells [1,2]. Suitable fluorescence probes are naturally of critical importance for fluorescence imaging. Recently, we found that hydroxymethyl rhodamine green (HMRG) was strongly fluorescent in aqueous solution at pH 7.4, while mono-amidated HMRG derivatives were colorless and non-fluorescent due to the preferred spirocyclized structure [3,4].

Based on above findings, we have developed various novel aminopeptidase-sensitive probes which were applicable for living cell system, including gGlu-HMRG, a novel HMRG-based “activatable” fluorescence probe for g-glutamyltranspeptidase (GGT). We could establish a novel and highly activatable strategy for sensitive and fast-responding fluorescence imaging of tiny tumors in vivo by spraying gGlu-HMRG onto tissue surfaces that are suspected of harboring tumors, creating high signal contrast between the tumor and the background within 1 min [5].

We have also developed a novel class of fluorophores which spontaneously and repeatedly blink with proper average lifetime of fluorescent state without any additives and special conditions, by optimizing the equilibrium constants of intramolecular spirocyclization and the rate constants of ring-closure reaction [6]. These are quite suitable for STORM super-resolution imaging technique, especially for live cell imaging, due to the capability of self-blinking without any additives of high concentration of thiols and strong irradiation of light for driving majority of fluorophores into dark state as is the case for conventional fluorophores. Indeed, by taking advantage of its spontaneous blinking property, STORM imaging of nuclear pore structures far above from coverslip under spinning-disk confocal microscopes and repetitive time-lapse super-resolution imaging of microtubules in live cells could be achieved [6]. Thus, our precisely designed spontaneously blinking fluorophore has a potential to expand the application of STORM technique deep into the cells and to track the motion of certain structure in living cells.

References1. Kamiya M, et al. J. Am. Chem. Soc., 133, 12960-12963 (2011).2. Urano Y, et al., Nature Med., 15, 104-109 (2009).3. Sakabe M, et al. J. Am. Chem. Soc., 135, 409-414 (2013).4. Kenmoku S, et al. J. Am. Chem. Soc., 129, 7313-7318 (2007).5. Urano Y, et al., Sci. Transl. Med., 3, 110ra119 (2011).6. Uno S, et al., Nature Chem., 6, 681-689 (2014).

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O-E2-01-01

The IMI European Lead Factory: New Opportunities for Drug Discovery

Dr Phil Jones

European Screening Centre Newhouse University of Dundee, Biocity Scotland, Bo’ness Road, Motherwell, Lanarkshire.

UK ML1 5UH [email protected]

The Innovative Medicines Initiative (IMI) European Lead Factory (www.europeanleadfactory.eu) is a major European project established with the aim of generating new lead structures for drug discovery projects in the public and private sectors. A Joint European Compound Library (JECL) has been established by combining selections of compounds from participating pharma companies. This collection of approximately 300,000 compounds will be supplemented during the course of the project with a further 200,000 compounds designed and synthesised specifically for the purpose based on contributed ideas from around Europe.

Screening of the library and follow-up of resulting hits will occur at the European Screening Centre based on two former Organon/MSD sites in Scotland and The Netherlands utilising state-of-the-art robotics for compound logistics and uHTS. Further characterisation of hits including initial medicinal chemistry will be available to public programs (academic and SME based). The desired output will be high quality hits that represent excellent starting points for drug discovery programs or tools for investigating and validating novel pharmacological approaches with the ultimate aim of creating benefit for patients.

This talk will explain the background and current status of this project and highlight opportunities to participate.

References

1. www.efmc.info/medchemwatch-2014-1/lab.php

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O-E2-01-06

Fishing for Drug Targets with Small Molecule Baits

Gerard Drewes

Cellzome GmbH, Meyerhofstrasse 1, D-69121 Heidelberg, Germany. [email protected]

Therapeutic strategies that target the catalytic activity or the recruitment functions of chromatin targets therefore hold great promise as pioneer epigenetic therapies. Many of the potential drug targets in-volved in chromatin modification are implicated in the formation of intricate networks formed by large protein complexes. We have developed a quantitative proteomics-based strategy which uses immobi-lized small molecule probes to assess drug binding to megadalton protein complexes. We will present data on the inhibition of protein complexes formed by enzymatic and non-enzymatic histone regulators – the lysine deacetylase enzymes (HDACs; Ref. 1), and the acetyl-lysine recognizing bromodomain adaptor proteins (BRDs; Ref. 2). We show that inhibitors of these chromatin modifiers bind to their targets in the context of large protein complexes, and that the proteomic binding data can be used to quantitatively differentiate complex subunits based on their small molecule inhibition properties. We will also demonstrate how these data can be used to guide the most promising therapeutic progression paths for this type of protein complex modifiers.

[1] Bantscheff, M., et al. (2011). Chemoproteomics profiling of HDAC inhibitors reveals selective targeting of HDAC complexes. Nature Biotechnology 29, 255-65 [2] Dawson, M.A., et al. (2011) In-hibition of BET recruitment to chromatin as an effective treatment for MLL-fusion leukaemia. Nature 478, 529-33

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O-E2-02-01

Heart Regeneration: Opportunities and Challenges for Drug Discovery using Physiologically Relevant Human Cells and a Variety of Chemical Modalities

Alleyn T. Plowright, Gabriella Brolen, Lauren Drowley, Ola Engkvist, Qing-Dong Wang AstraZeneca R&D Mölndal, Sweden


The use of physiologically relevant human cells, including primary cells from patients and human in-duced pluripotent stem cells, in compound phenotypic screening and toxicology testing, has the poten-tial to transform drug discovery and lead to significantly improved outcomes in clinical development. Application of high content screening (e.g. multi-lineage differentiation), use of defined biologically active and annotated compound libraries combined with pathway analyses to phenotypic screens using these cells can maximize the knowledge gained and provide compound hits and targets relevant to modifying human disease. This talk will describe the use of relevant human cells combined with high content image analysis, testing of biologically annotated compound libraries along with the appropriate computational and bioinformatic tools to help decipher and understand potential targets, molecules as well as alternative modalities to small molecules that can successfully modify disease. Challenges lay ahead including target confirmation/deconvolution and the potential need to optimize chemistry against multiple targets. This presentation will describe advances in this area, including application in the field of identifying novel therapeutics for regeneration of cardiac tissue, and discuss the exciting opportuni-ties as well as challenges that this approach will provide.

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O-E2-02-02

FROM MALARIA BOX TO PATHOGEN BOX: CATALYZING NEGLECTED DISEASES DRUG DISCOVERY

Thomas SpangenbergMedicines for Malaria Venture, ICC - Geneva, Switzerland

[email protected]

To catalyse malaria research a unique screening tool has been devised and made accessible to researchers free of cost: the Malaria Box [1]. It is a collection of 400 diverse compounds selected from ~20,000 structurally unique molecules that were shown to have confirmed activity against the blood-stage of Plasmodium falciparum in 3 large phenotypic high-throughput screening campaigns undertaken by GlaxoSmithKline [2], Novartis-GNF [3], and St. Jude Children’s Research Hospital [4] (Figure 1). The idea was to provide the research community with a collection of starting points for hit-to-lead drug discovery programmes and a tool to facilitate the understanding of the underlying parasite and host biology. The Malaria Box is assembled from commercially available compounds that also allows the sourcing of their near neighbors for rapid confirmation of activity and exploration of structure activity relationships. Significantly, the scope of the Malaria Box extends beyond the malaria field; compounds active against malaria have utility in other parasitic or neglected diseases. This enables the community to better understand the link between malaria and other parasitic or orphan diseases by allowing the mining of data sets previously not considered. Also this project has triggered a second open access initiative: the Pathogen Box.

Figure 1. Selection process for the Malaria Box

References1. Spangenberg T, Burrows JN, Kowalczyk P, McDonald S, Wells TNC, Willis P. PLoS One 8:e62906 (2013).2. Gamo F-J, Sanz LM, Vidal J, de Cozar C, Alvarez E, Lavandera J-L, Vanderwall DE, Green DVS, Kumar V, Hasan S, Brown JR, Peishoff CE, Cardon LR, Garcia-Bustos JF. Nature. 465:305-310 (2010)3. Meister S, Plouffe DM, Kuhen KL, Bonamy GM, Wu T, Barnes SW, Bopp SE, Borboa R, Bright AT, Che J, Cohen S, Dharia NV, Gagaring K, Gettayacamin M, Gordon P, Groessl T, Kato N, Lee MC, McNamara CW, Fidock DA, Nagle A, Nam TG, Richmond W, Roland J, Rottmann M, Zhou B, Froissard P, Glynne RJ, Mazier D, Sattabongkot J, Schultz PG, Tuntland T, Walker JR, Zhou Y, Chatterjee A, Diagana TT, Winzeler EA.. Science. 334:1372-1377 (2011)4. Guiguemde WA, Shelat AA, Bouck D, Duffy S, Crowther GJ, Davis PH, Smithson DC, Connelly M, Clark J, Zhu F, Jiménez-Díaz MB, Martinez MS, Wilson EB, Tripathi AK, Gut J, Sharlow ER, Bathurst I, Mazouni FE, Fowble JW, Forquer I, McGinley PL, Castro S, Angulo-Barturen I, Ferrer S, Rosenthal PJ, DeRisi JL, Sullivan DJ, Lazo JS, Roos DS, Riscoe MK, Phillips MA, Rathod PK, Van Voorhis WC, Avery VM, Guy RK. Nature. 465:311-315 (2010)

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O-E2-03-01

From Covalent Glycosidase Inhibitors To Activity-Based Glycosidase Probes

Herman Overkleeft

Leiden Institute Of Chemistry, Leiden University;The Netherlands [email protected]

Activity-based protein profiling has emerged as a powerful discovery tool in chemical biology and medicinal chemistry research. Success of activity-based protein profiling hinges on the presence of compounds that can covalently and irreversibly bind to enzymes, do so selectively in the context of complex biological samples and subsequently report on the selected pool of proteins. Such tagged molecules featuring an electrophilic trap, termed activity-based probes, have been developed with most success for serine hydrolases and various protease families (serine proteases, cysteine proteases, proteasomes). In this lecture I will present our current progress in the design of activity-based probes targeting retaining glycosidases, enzymes that employ a double displacement mechanism in the hydrolysis of glycosidic bonds with overall retention, thus form a covalent intermediate with their substrates during the catalytic process and are therefore amenable to activity-based protein profiling studies. I will present design parameters through which a number of lysosomal retaining glycosidases can be addressed by activity-based probes. Our current probe set includes probes for retaining alpha fucosidase, retaining beta-glucuronidase, retaining alpha-galactosidase and retaining beta-glucosidase activities, enzymes of interest in lysosomal storage disorders. The application of the probes to monitor enzyme activity in the context of Gaucher disease (acid glucosylceramidase) and Fabry disease (alpha-galactosidase) will be discussed and future directions in which the probes will serve as tools to monitor enzyme inhibitors in situ and in vivo will be presented.

References

1. M. D. Witte, W. W. Kallemeijn, J. Aten, K.-Y. Li, A. Strijland, W. E. Donker-Koopman, B. Blijlevens, G. Kramer, A. M. C. H. van den Nieuwendijk, B. I. Florea, B. Hooibrink, C. E. M. Hollak, R. Ottenhoff, R. G. Boot, G. A. van der Marel, H. S. Overkleeft, J. M. F. G. Aerts, Nat. Chem. Biol. 6, 907 (2010).

2. W. W. Kallemeijn, K.-Y. Li, M. D. Witte, A. R. A. Marques, J. Aten, S. Scheij, J.-B. Jiang, L. I. Willems, T. M. Voorn-Brouwer, C. P. A. A. van Roomen, R. Ottenhoff, R. G. Boot, H. van den Elst, M. T. C. Walvoort, B. I. Florea, J. D. C. Codée, G. A. van der Marel, J. M. F. G. Aerts, H. S. Overkleeft, Angew. Chem. Int. Ed. 51, 12529 (2012).

3. M. T. C. Walvoort, G. A. van der Marel, H. S. Overkleeft, J. D. C. Codée, Chem. Sci. 4, 897 (2013).

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O-F1F2-01-01

Quantitative Proteomics: From Discovery Phase To Functional Investigation

A.Bachi,

IFOM-FIRC Institute of Molecular Oncology, 20139 Milan, Italy

Thanks to technological innovations in mass spectrometry, proteomics has recently evolved from the identification of thousands of proteins that compose a biological sample into the comprehensive qualitative and quantitative detection, measurement and mapping of complex molecular systems.

In our lab we apply quantitative proteomics [1] to address biomedical issues. I will present different mass spectrometry-based quantitative proteomics approaches (both metabolic labeling or label free) for discovery or targeted proteomics [2,3] and discuss advantages and pitfalls of each strategy.

In particular, I will present examples of SILAC-based quantitative proteomics [4] to study i) protein-protein interaction dynamics in order to elucidate how a point mutation, responsible for the onset of a monogenic autoimmune disease, can affect the functional protein interaction network and ii) to elucidate the microvescicles-mediated crosstalk between neural precursor stem cells and the recipient cells. I will also discuss quantitative label free proteomic approaches, based on high resolution and high mass accuracy mass spectrometry, to identify new biomarkers for Chronic Lymphocytic Leukemia (CLL) and for salt-sensitive and salt resistant hypertensive patients

References

1. A. Bachi and T. Bonaldi, J.Prot 71(3):357-67 (2008).

2. A. Bensimon, A.J. Heck and R. Aebersold, Annu Rev Biochem.;81:379-405 (2012).

3. E.Sabidó , N. Selevsek N, and R. Aebersold, Curr Opin Biotechnol 23(4):591-7 (2012)

4. M.Mann. Methods Mol Biol. 1188:1-7 (2014).

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O-F1F2-02-01

Bioanalytics and Molecular Biology to improve Understanding of Intracellular Nanoparticle Drug Delivery

Volker Mailänder1,2, Daniel Hofmann1,2

1 Max Planck Institute for Polymer Research, Ackermannweg 10, 55128 Mainz, Germany 2 III. Medical Clinic, Hematology, Oncology and Pneumology, University Medical Center of the

Johannes-Gutenberg University Mainz, Langenbeckstr. 1, 55101 Mainz, Germany Presenting author: [email protected]

Rational design of nanocarriers for drug delivery approaches requires an unbiased knowledge of uptake mechanisms and intracellular trafficking pathways. Ways to investigate these processes using a quantitative proteomics approach as well as molecular biology will be discussed. Isolation of intracellular vesicles containing superparamagnetic iron oxide polystyrene nanoparticles and methods how to dissect their protein composition by label free quantitative mass spectrometry will be presented. As an example how this can yield new insights the proteomic snapshot of organelle marker proteins indicating an atypical macropinocytic-like mechanism used for the entry of nanoparticles is demonstrated. We show that the entry mechanism is controlled by actin reorganization, atypical macropinocytic signaling and ADP-ribosylation factor 1. Additionally, this proteomics approach demonstrated a central role for multivesicular bodies and multilamellar lysosomes in trafficking and final nanoparticle storage. This is confirmed by confocal microscopy and cryo-TEM measurements. By quantitatively analyzing the protein composition of nanoparticle-containing vesicles, we demonstrate a methodoloy how to clearly define the routes of nanoparticle entry, intracellular trafficking and the proteomic milieu of a nanoparticle-containing vesicle.

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O-F3-01-01

Ions, amphiphiles and specific effects at aqueous interfaces

R. Scheu1, Y. Chen1, S. Roke1

1Laboratory for fundamental BioPhotonics (LBP), École Polytechnique Fédérale de Lausanne (EPFL) Institute of Bio-engineering (IBI), School of Engineering (STI), CH-1015 Lausanne,

Switzerland Presenting author: [email protected]

Life occurs in three dimensional turbid aqueous systems. A cell consists for ~60 % of water and contains many organelles and interfaces. The average distance between two molecules, or a molecule and a membrane interface is approximately 1 nm. The molecular, structural, dynamic, and biological properties of water, aqueous systems and aqueous interfaces are essential in understanding the complexity of life, and our ability to harness its features for novel (nano)technologies.

Here, I will introduce nonlinear optical scattering methods that can be used to gain label-free molecular level information about liquid aqueous systems and nanoscopic interfaces in turbid media. The use of these methods will be illustrated around a few questions relating to the intriguing response of water to charge on various levels:

• What is the molecular structure in the electric double layer [1]?

• What is the role of water in determining the stability of charged amphiphilic interfaces [2]?

• Does water behave charge asymmetrically [3]?

References

[1] R. Scheu, Y. Chen, M. Subinya, S. Roke, J. Am. Chem. Soc. (2013), 135, 19330 – 19335

[2] R. Scheu, Y. Chen, H. B. de Aguiar, B. M. Rankin, D. Ben-Amotz, S. Roke, J. Am. Chem. Soc. (2014), 136, 2040 – 2047

[3] R. Scheu, B. M. Rankin, Y. Chen, K. C Jena, D. Ben-Amotz, S. Roke, Angew. Chem. Int. Ed., (2014), in press.

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O-F3-02-01

Coherent Raman spectroscopy in the single molecule limit

Eric O. Potma1

1Department of Chemistry, University of California, Irvine, CA 92697, USA


Detecting coherent anti-Stokes Raman scattering (CARS) signals from signal molecules is a longstanding experimental challenge. Driving the vibrational CARS response with surface plasmon fields has proven notoriously difficult due to strong background contributions, unfavorable heat dissipation and the phase dispersion of the plasmon modes in the ensemble.

1,2 In this work we overcome previous

experimental limitations and demonstrate time-resolved, vibrational CARS from molecules in the low copy limit, down to the single molecule limit. Our measurements, which are performed under ambient and non-electronic resonance conditions, establish that the coherent response from vibrational modes of individual molecules can be studied experimentally, opening up a new realm of molecular spectroscopic investigations.

Figure 1: Rendering of a bipyridyl-ethylene molecule and its plasmonic antenna used in the time-resolved CARS measurements.

References

1 Y. Wang, C.Y. Lin, A. Nikolaenko, V. Raghunathan, and E. O. Potma, “Four-wave mixing microscopy of nanostructures,” Adv. Opt. Photon. 3, 1-52 (2011).

2 X, Hua, D. V. Voronine, C. W. Ballman, A. M. Sinyokov, A. V. Sokolov, and M. O. Scully, “Nature of surface-enhanced coherent Raman scattering,” Phys. Rev. A 89, 043841 (2014).

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O-F3-03-01

Preparation and study of semiconductors with a honeycomb nanogeometry

D. Vanmaekelbergh 1, M.P. Boneschanscher1 , J.J. Geuchies1 , C. van Overbeek1, C. Morais Smith1, W. H. Evers2, C. Delerue3, S. Bals4

1University of Utrecht, Utrecht, The Netherlands 2Technical University of Delft, The Netherlands

3IEMN-ISEN, Lille, France 4University of Antwerp, Antwerp, Belgium

Presenting author: D. [email protected]

The interest in 2-dimensional systems with a honeycomb lattice and related Dirac-type electronic bands has exceeded the prototype graphene. Currently, 2-dimensional atomic and nanoscale systems are extensively investigated in the search for materials with novel electronic properties that can be tailored by geometry. I will show how atomically coherent honeycomb superlattices of rocksalt (PbSe, PbTe) and zincblende (CdSe, CdTe) semiconductors can be obtained by nanocrystal self-assembly, covalent attachement, and subsequent cation exchange [1-3]. I will also discuss the chemical passivation of the formed honeycomb semiconductors using halide salts. Atomistic theory and analytical predict that these artificial graphene systems combine Dirac-type electronic bands with the beneficial properties of a semiconductor, such as the presence of a band gap and strong spin-orbit coupling, leading to the quantum spin Hall effect [4]. I will present the first experimental results on the opto-electrical characterisation of PbSe and CdSe honeycomb semiconductors.

References1. W. H. Evers et al., Nanoletters 13, 2317 (2013).2. M.P. Boneschanscher et al., Science 344, 1377 (2014).3. M. A. Boles and D. V. Talapin, Science 344, 1340 (2014).3. E. Kalesaki et al., PRX 4, 011010 (2014).

Figure 1: HAADF-STEM image of a honeycomb superlattice prepared by interfacial self-assembly of monodisperse PbSe nanocrystals. The entire honeycomb structure is atomically coherent. The individual nanocrystal building blocks can be observed in the nano-footstep.

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O-F4-01-01

Surface assisted synthesis and STM-characterization of functional organic nanosystems

Harald Fuchs

Physikalisches Institut and Center for Nanotechnology (CeNTech) Westfälische Wilhelms-Universität Münster, Germany

The formation of chemical bonds depends strongly on the spatio-temporal conditions within an ensemble of starting molecules. We found that by using nanostructured surfaces on metallic single crystals, a significant increase of the reaction rate can be obtained, even with simple linear hydrocarbons exhibiting very poor chemical reactivity. By imposing appropriate self-organized nano-confinements on the metallic surface which promote heterogeneous catalysis, polymerization of the linear monomeric units at mild conditions is obtained via CH-activation. The concept can be extended to 2-dimensional Glaser-coupling reactions on low indexed surfaces. The examples presented demonstrate new pathways to generate specific chemical bond formation which is unlikely to occur with conventional chemical techniques. The experiments were done with STM/STS, supported by DFT calculations and photo-electron spectroscopy (PES). The influence of reduced dimensionality of a surface and steric properties of the educts on the enantiomer selectivity as well as catalytic effects of surfaces and additional ad-atoms are discussed.

www.uni-muenster.de/Physik/PI/Fuchs

www.centech.de

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O-F4-02-01

Smart polymer brushes: Molecular response by AFM

G. Julius VancsoUniversity of Twente, Materials Science and Technology of Polymers,

MESA+ Institute for Nanotechnology, 7500 AE Enschede, the Netherlands. E-mail: [email protected].

The last decades have witnessed tremendous growth in the field of science and technology of advanced macro-molecular materials. Achievements in polymer chemistry provided new, stimulus responsive (“smart”) macro-molecules with hitherto unprecedented structural control, precision, and ease of synthesis. Materials surfaces can now be functionalized with such polymers using e.g. controlled free radical polymerizations in “grafting from” approaches in a controlled fashion. “Smart” polymer grafts respond in an abrupt, and often dramatic, way to small variations of external stimuli. This response for polymer brushes depends (in addition to the chemical structure of the chains) on structural parameters, such as length and length distribution of the grafts, their solubility, and grafting density. Quantitative analysis and characterization of these parameters remains a grand challenge. To tackle this challenge, atomic force microscopy (AFM) based methods offer opportunities; some of these will be highlighted in this presenta-tion [1]. In the first example temperature responsive grafts will be discussed [2]. The synthesis process of thermosensitive surfaces, including controlled grafting of poly(N-isopropylacrylamide) (PNIPAM) brushes will be elucidated. PNIPAM brushes were grafted in a controlled manner from mixed self-assembled monolayers (SAMs) on Au substrates. This process allows the production of tunable, temperature-responsive PNIPAM tethers. The length of the chains can be controlled by the irradiation time, whereas the grafting density can be adjusted with SAM mixing ratios. Variation of the adhesion and friction of the brush due to swelling and collapse is monitored by AFM as a function of the temperature crossing the lower critical temperature (LCST) transition. Isothermal col-lapse of PNIPAM brushes in the mixed solvent system water/methanol 50% v/v is demonstrated by in-situ AFM and ellipsometry. Based on AFM experiments and simulations of ellipsometry data we postulate a structural model, which assumes that collapse takes place in the contacting layer between brush and co-nonsolvent and the top-collapsed brush remains hydrated in the film interior. AFM based friction force microscopy shows a large in-crease of the friction coefficient of PNIPAM grafts when the grafts swollen by water are brought in contact with co-nonsolvents. This section of the presentation will be complemented by single-molecule AFM based force spectroscopy data in an attempt to connect responsive ensemble behavior with single chain response.In the next section we show how AFM can be used in compression to determine the values of grafting density and brush thickness [3]. We employed the Alexander-de Gennes model and colloid particle modified AFM probes to determine the values of these variables.In case of two contacting brush systems, interdigitation of opposing brushes makes them prone to damage [4]. We briefly show that immiscible brush systems can form slick interfaces, in which interdigitation is eliminated and dissipation strongly reduced. Results are based on numerical simulations, and on AFM friction force micros-copy experiments on hydrophilic and hydrophobic brush systems in both symmetric and asymmetric configura-tions. Our results reveal that two immiscible brush systems in mechanical contact slide at a fluid–fluid interface while having load-bearing ability.

References[1] Sui, X., Zapotoczny, S., Benetti, E.M., Schön, P., Vancso, G.J.; Characterization and molecular engineering of sur-face-grafted polymer brushes across the length scales by atomic force microscopy (2010) Journal of Materials Chemistry, 20 (24), pp. 4981-4993.[2] (a) Benetti, E.M.; Zapotoczny, S.; Vancso, G.J. (2007) Advanced Materials, 19, 268-271. (b) Sui, X.; Chen, Q.; Hempenius, M.A.; Vancso, G.J. (2011) Small, 7, 1440-1447. (c) Chen, Q.; E. Kooij, E.S.; Sui, X.; Padberg, C.J.; Hempe-nius, M.A.; Schön, P.M.; Vancso, G.J. (2014) Soft Matter, 10 (17) 3134-3142. [3] Kutnyanszky, E., Vancso, G.J. Nanomechanical properties of polymer brushes by colloidal AFM probes(2012) European Polymer Journal, 48 (1), pp. 8-15.[4] de Beer, S.; Kutnyanszky, E.; Schön, P.M.; Vancso, G.J.; Müser, M.H. (2014) Nature Communications, 5¸DOI: 10.1038 ncomms4781.

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O-F4-04-01

Electron microscopy as a unique tool to investigate wetting at the nanoscale

L. Isa, 1 Laboratory for Interfaces, Soft Matter and Assembly, Department of Materials, ETH Zurich, HCI

H525, Vladimir Prelog Weg 5, CH-8093 Zürich, Switzerland


New materials obtained by the self-assembly of micro- and nanoparticles (MPs and NPs) at fluid interfaces hold the potential to impact many technological applications, including functional membranes and delivery vehicles. Despite impressive developments in the synthesis of complex MPs and NPs, the quest for a general way to control the properties of the final material starting from the properties of the building blocks still faces outstanding open challenges. True progress is often hindered by the lack of control and in situ characterization of the basic particle properties and of the way in which they interact.

I will describe a recently developed methodology, based on freeze-fracture and cryo-SEM, which allows us for the first time to measure in situ at oil-water interfaces the three-dimensional location, and thus the contact angle, of individual particles as small as 10 nm in diameter [1, 2]. I will the present its application to several systems of fundamental and applied interest, including deformable hydrogel particles used as novel emulsion stabilizers [3, 4], surfactant adsoprtion for double emulsion inversion [5], Janus [6] and anisotropic microparticles [7].

Figure 1: Schematic representation of freeze-fracture, shadow-casting cryo-SEM for particle contact angle measurements for different particle wettability.

References

1. L. Isa, F. Lucas, R. Wepf and E. Reimhult, Nature Communications, 2:438, (2011).2. L. Isa, CHIMIA, 67 (4), 231-235, (2013).3. K. Geisel, L. Isa and W. Richtering, Langmuir, 28 (45), 15770–15776, (2012).4. K. Geisel, L. Isa and W. Richtering, Angewandte Chemie, DOI:10.1002/anie.201402254, (2014).5. B.P. Binks, L. Isa and A.T. Tyowua, Langmuir, 29 (16), 4923–4927, (2013).6. A. Synytska, A. Kirillova and L. Isa, ChemPlusChem, DOI: 10.1002/cplu.201400020, (2014).7. S. Coertjens, P. Moldenaers, J. Vermant and L. Isa, Langmuir, DOI: 10.1021/la500888u, (2014).

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BS-01-01

DEEP INSIGHT INTO THE MULTICOMPONENT UGI AND UGI-SMILES REACTION MECHANISM BY ESI-MS(/MS)

C. Iacobucci1, S. Reale1, J.-F. Ga2, F. De Angelis1

1 Dipartimento di Scienze Fisiche e Chimiche, Università dell’Aquila, Via Vetoio-Coppito II, I-67100, L’Aquila, Italia

2 Institut de Chimie de Nice, Université Nice Sophia Antipolis, CNRS-UMR 7272, Parc Valrose, 06108 Nice Cedex 2, France


The Ugi four-component reaction (U-4CR), named after the German chemist Ivar Karl Ugi, is one of the most prominent multicomponent reactions in organic synthesis. Originally developed to synthesise α-aminoacyl amide derivatives, the U-4CR provides access to a wide range of scaffolds by employing bifunctional substrates or varying some of them. Since its discovery in 1959, the reaction mechanism of the U-4CR has aroused great interest by the chemist community, and it is still a matter of debate. Two possible condensations pathways have been proposed: i) the original pathway, introduced by Ugi himself; ii) a more recent one which points to a delayed isocyanide insertion – this being the key reaction step in the overall process. Only very recently the U-4CR mechanism has been investigated also by ESI-MS (Electrospray Ionisation Mass Spectrometry) by M. Eberlin et al. by exploiting charged ion-tagged reagents [1]. During the last few years in fact, MS has gained widespread acceptance as a technique for mechanistic studies of organic reaction and catalysis.

By exploiting the mentioned ESI-MS potentialities, enriched in our case by High Resolution (HR) measurements obtained with Q-ToF analyser, but reasoning also that the use of ion-tagged reagents might alter the reaction pathway and intermediates stabilities because of the introduction of the polar hook, we have developed and present here a tailor-made combination of reaction conditions devoid of any charged molecular devise, with accurately selected ESI-MS settings, to disperse the fog upon every detail of the Ugi, and also of the Ugi-Smiles multicomponent reaction mechanisms. Very remarkably, all our experimental results are in agreement in every detail with Fleurat-Lessard et al. theoretical energy profile [2].

Characterisation of the isomeric species of the Mumm rearrangement (key equilibrium along the reaction path) in the gas phase was also performed by using MS/MS.

References

1. G.A. Medeiros, W.A. da Silva, G.A. Bataglion, D.A.C. Ferreira, H.C.B. de Oliveira, M.N. Eberlin and B.A.D. Neto, Chem. Commun. 50, 338-340 (2014).

2. N. Chéron, R.Ramozzi, L. El Kaim, L. Grimaud, and P. Fleurat-Lessard J.Org. Chem. 77, 1361-1366 (2012).

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BS-01-02

RECOVERY OF FLUOROUS Pd CATALYSTS

Ling-Kang LIU

Institute of Chemistry, Academia Sinica, Nangang, Taipei 115, TAIWAN Presenting author: [email protected]

To demonstrate applications on Pd catalyst recovery, a series of fluorinated 2,2′-bpy ligands (1) were prepared and metallated to give (4,4′-bis(RfCH2OCH2)-2,2′-bpy)PdCl2 catalysts (2). Compounds 2 were found to be thermally stable to >300 °C. The Pd catalysts 2 gave quantitative conversion with Heck reactions below (Schemes 1 and 2).

N

N

ORf

ORf N N

ORf

ORf

PdCl Cl

(EtCN)2PdCl2

1 2

Rf

n-C3F7-

HCF2(CF2)3-

HCF2(CF2)7-

n-C8F17-

n-C10F21-

n-C11F23-

abcdef

IOZ

O

OZ

ORecycl. Cat. 2

Heck ReactionYHMeOMeNO2

ZHMe

YY

Scheme 1

Scheme 2

A number of means to recover and recycle of the Pd catalysts are demonstrated below:

(a) As the catalysts are thermally stable, the recovery could be achieved by distillation. The catalysts 2a–c remained in reaction vessel while the products were transferred to the receiver vessel.

(b) With much greater fluorophilicity, the catalysts 2d–f are orders of magnitude more soluble in fluorous solvents than in common organic solvents. Insoluble in organic solvents at 25°C and slightly soluble in organic solvents at > 120°C, the fluorinated Pd complexes performed in Heck reactions as catalyst under a fluorous biphasic catalysis condition. The reaction proceeded at > 120°C and upon completion the Pd catalysts 2d–f were recovered by separation of the fluorous layer from the organic layer after cooling the product mixtures to settle into two layers. The catalysts 2d–f stay in the fluorous layer.

(c) A third way was to run the Heck reactions under a thermomorphic mode using Pd catalysts 2d–f at 140°C homogeneously, at which the Pd complexes have suitable solubility in the organic solvent. Upon returning to room temperature after reaction, the Pd catalysts 2d–f precipitated readily because of insolubility and the product mixtures remained in solution.

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BS-01-03

An Unconventional And Unique Contribution from the Institute of Chemistry Ceylon (Ichemc) to Human Resource Development in Sri Lanka Throh the Production of Professional Graduate

Chemists And Chemistry Technicians Over a Four Decade Period

J.N.Oleap Fernando

Honorary Rector,College of Chemical Sciences, Institute of Chemistry Ceylon 341/22, Professor M U S Sultanbawa Mawatha, ,Kotte Road, Welikada, Rajagiriya, Sri Lanka

Our professional body (IChemC) has made an exceptionally productive,meaningful and significant contribution to HRD in Sri Lanka through the production of 969 Graduate Chemists & 945 Chemistry Technicians. IChemC has thus become the largest producer of Graduate Chemists and the only provider of Chemistry Technicians.The Graduateship Programme in Chemistry(with direct support and guidance from the Royal Society of Chemistry,UK) and the Diploma in Laboratory Technology Programme in Chemistry which were commenced four decades ago have enabled this human resource development. These programmes have developed exponentially over these years with much popular appeal & increased enrollment to become significant characteristics in the tertiary educational scenario in Sri Lanka. These programmes continue to meet a much essential need & have been able to accommodate a huge demand to supplement the woeful shortage of qualified chemistry personnel from the non-fee levying state university sector. This has enabled not only school leavers but also late developers, late realisers, adults and the employed to follow an internationally(RSC) accredited Graduateship Programme that has earned international recognition for postgraduate registration/achievements(PhD/MPhil/MSc),multifaceted employment and relevant career redirections in an unprecedented but most welcome manner. The Technician Diploma has enabled a unique opening in Sri Lanka for middle level training in support of research and analytical services in scientific,medical,food & industrial laboratories. The conduct of these (not for profit/service oriented) programmes have also made it possible, as an unexpected spin off benefit to enable IChemC,which had basically no infrastructure(in terms of office,staff,buildings etc) four decades ago not only to now possess such facilities in full measure but also to become financially more stable as a result. Although our mission was always fully altruistic with the objective of providing a necessary professional service and meet essential needs, it has now made the Institute’s College of Chemical Sciences(CCS) an indispensable and internationally recognized higher educational institute with a solid foundation & a bright future in Sri Lanka..A lacuna in HRD in Chemistry has been filled, the professional status of the Chemist has got more enshrined and the profession of Chemistry has become nationally recognized amongst all the relevant sectors in Sri Lanka. The Ruby(40 th) anniversary of professional chemistry educational programmes was marked in early April with the holding of an International Conference on Chemical Education, during which the 65 th Executive Committee meeting of our Federation was also held in Colombo for the second time in FACS history. This would never have been possible without the available professional/educational infrastructure of IChemC/CCS, which is now even able to enroll global applicants for both programmes. The charges of about US $ 4,500 for the 4 year Graduateship Programme & US $ 1,000 for the 2 year Laboratory Technician programme are perhaps the lowest in the world for similar tertiary programmes.

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BS-01-04

ECTN - EUROPEAN CHEMISTRY THEMATIC NETWORK ASSOCIATION

F. De Angelis ECTN President: @Dipartimento di Scienze Fisiche e Chimiche, Università dell’Aquila, L’Aquila, Italia

[email protected] and [email protected]

The European Chemistry Thematic Network (ECTN) Association is a non-profit making association registered in Belgium, founded in 2002 as an outcome of six years of European network activity (1996-2002). The Association was created to provide a sustainable future for the European network. Since its foundation, ECTN association acts as an important player in the European arena of higher education (HE). Universities and other higher education institutions, and also national chemical societies are ECTN members. These are currently over 120 from 30 different European countries, with associate members world-wide.Aims and objective of the Association are (new Statutes - Madrid GA of April 2014):

- Implementing programmes for the assessment of skills and knowledge in Chemistry. - Undertaking programmes on education and training, with innovative approaches.- Fostering internationalisation of education programmes.- Pursuing programmes for exchange of teachers and students.- Providing certification of achievement at various levels of competences in chemistry.- Providing the chemical community with printed and electronic publications and dissemination

media in higher education.- Setting, monitoring, validating quality standards/goals in higher education in chemistry.- Cooperating with established European associations in the furtherance of its objectives.- Extending the reach of all aspects of education in Chemistry beyond national borders.

ECTN active bodies are working groups and standing committees. The SCs, in particular, focus their activities onto specific targets relevant to assessment of skills/competences and validation of curricula in chemistry and scientific disciplines in general. These are:

- the Label Committee (LC), which sets, monitors and renews quality goals in higher education in chemistry, assesses quality standards and provides quality accreditation of higher education courses to individual institutions. Its products are the Eurobachelor®, the Euromaster®, and the Chemistry Doctorate Eurolabel.

- the Virtual Education Community (VEC), which provides certification of achievement at various levels of competences in chemistry by printed and electronic means, and also provides the chemical community with printed and electronic publications and dissemination media in higher education.

Along with the lines presented in the 2013 State of the Union address by President Barroso, who stated that «the better use of science, research and innovation potential is a pre-condition for sustaining and enhancing Europe’s competitiveness, growth and jobs», ECTN is currently fostering new objectives, by i) innovating its regulations and structure, to pursue its objectives in a more organised and effective way; ii) finding robust cooperation with key partners, for maintaining its excellence in undertaking programmes concerning training, higher education and knowledge validation in chemistry; iii) ECTN continues to be characterised by its key values: intellectual independence, excellence, loyalty, integrity, transparency; iv) ECTN wants to become an influential European body at the policy level in Brussels, for any decision that should be taken in Europe as far as the higher chemical education is concerned. The “ECTN Newsletter” (http://www.ec2e2n.info) is published regularly.

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BS-02-01

Fluorescence sensing of intracellular glutathione and activation of “caged” photodynamic sensitizers

Engin U. Akkaya

Department of Chemistry and UNAM-National Nanotechnology Research Center Bilkent University, 06800 Ankara, Turkey.

Photodynamic therapy (PDT) is a noninvasive method of treating malignant tumors and age-related macular degeneration, and it is particularly promising in the treatment of multidrug-resistant tumors. The PDT strategy is based on the preferential localization of certain photosensitizers in tumor tissues upon systemic administration. The sensitizer is then excited with red or near infrared (NIR) light, generating cytotoxic singlet oxygen (1O2) and thus irreversibly damaging tumor cells. Current practice of PDT is limited to a few functionalized porphyrins and related compounds, however these are not considered to be ideal photosensitizers for use in PDT. Among the limitations, the most prominent is the low extinction coefficient of porphyrins in the body’s therapeutic window (650–800 nm). As a consequence, many research groups worldwide are engaged in efforts to develop better sensitizers. One important aspect is the tight control of the photophysics of singlet oxygen generation. This can be achieved by coupling sensing of a cancer related parameter to the singlet oxygen generation process. In an earlier design, we proposed a sensitizer which behaves as an “AND” logic gate. Singlet excited state of the sensitizer dye can take a number of different paths for de-excitation, through competing processes. Among these processes, photoinduced electron transfer, intersystem crossing, fluorescence, non-radiative de-excitation are the most prominent ones. Control of the relative rates of these processes can potentially offer new sensitizers with improved selectivity and function.

Glutathione is an important cancer related intracellular species. We designed and synthesized caged photosensitizers which are inactive until they are acted upon by GSH. We demonstrate that sensing and therapeutic action are very much related. The methodology and the potential of our activatable photosensitizer design will be discussed.

The financial support by TUBITAK (112T480) is gratefully acknowledged.

References:

‘Designing Excited States: Theory-Guided Access to Efficient Photosensitizers for Photodynamic Action’ Y. Çakmak, et al., Angew. Chem. Int. Ed., 2011, 50, 11937-11941.

Cascading of Molecular Logic Gates for Advanced Functions: A Self-Reporting, Activatable Photosensitizer’ S. Erbaş-Çakmak, E. U. Akkaya, Angew. Chem. Int. Ed., 2013, 52, 11364 –11368.

Proof of principle for a molecular 1 : 2 demultiplexer to function as an autonomously switching theranostic

device’ S. Erbaş-Çakmak, et al., Chem. Sci., 2013, 4, 858–862.

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BS-02-02

Protein (misfolding) in relation to disease

Saskia M. van der Vies

Department of Pathology, VU University medical center, Neuroscience campus Amsterdam, De Boelelaan 1117, 1081HV Amsterdam, The Netherlands

Under normal circumstances, the cell has mechanisms to prevent proteins from folding incorrectly, as well as to get rid of misfolded proteins. Proteins that have problems achieving their native configuration are helped by molecular chaperones to fold properly, using energy from ATP. Molecular chaperones can avoid the conformational change that is required the for aggregation of the altered proteins and thus are fundamental to prevent protein misfolding. Despite molecular chaperone actions, some proteins still misfold, but there is a remedy: The misfolded proteins can be detected by quality-control mechanisms in the cell that tags them to be sent to the cytoplasm, where they will be degraded. When misfolding occurs the protein becomes toxic, as extensive conformational changes occur and beta sheet structure dominate. The abnormal conformational transition from alpha helix to beta sheet exposes hydrophobic amino acid residues and promotes protein aggregation. Prime examples of aggregated protein in neuro-degeneration are: prion protein, Tau, Abeta, alpha-synuclein, Huntington and TDP43. A short overview will be presented to highlight how protein misfolding leads to neurodegeneration and what tools we have to investigate neurodenegerative diseases, with a focus on Alzheimer’s disease.

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BS-02-03

Ethno mycological survey and biological activities of mushroom extracts against Escherichia coli and Staphylococcus epidermidis from Papua New Guinea (PNG)

John K Nema1, Stewart Wossa2, Edwin Costillo2, Basil Marasinghe1, Jeyarathan Pooranalingam1, Russell Barrow2

1School of Science & Technology, University of Goroka, Papua New Guinea, Email: [email protected]

2Research School of Chemistry, Australian National University, Australia,

Ethno mycological survey of more than 60 edible and non edible mushroom species was undertaken in the Siane area of Simbu Province in Papua New Guinea (PNG). Ethno mycological information obtained was used as a guide to prepare mushroom extracts of the Ganodermataceae family. The concentrated mushroom extracts were tested for their antibacterial properties against Escherichia coli and Staphylococcus aureus using 96 well plate method at the Research School of Chemistry at the Australian National University (ANU). The results showed that Ganoderma extracts (KMsp001 and KMsp002) prove to be moderately active against S.aureus with a growth inhibition of 34 and 47% respectively and KMSp 002 was also active against E.coli with growth inhibition of 26%. The Ganoderma species and their growth inhibition reported here were never reported in previous studies.

The Siane people in PNG are found to be myco-philic through this study. They have a systematic knowledge on the naming systems of the edible and non edible mushrooms but their knowledge on medicinal uses were limited. The naming systems of the mushrooms in the area were well developed. The mushrooms were named according to their colour, size, the substrate on which they grow, the shape and the length of the stipe. It is estimated that more than 100 species inhibit the forest of the study location.

Key words: PNG, ethno-mycology, growth inhibition,

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BS-02-04

Fluorine Chemistry in China

Long Lu

Key Laboratory of Organofluorine Chemistry, Shanghai Institute of Organic Chemistry, Chinese Academy of Sciences, 345 Lingling Road, Shanghai 200032

[email protected]

Fluorine-containing compounds are at the leading edge of many new developments in the life science industry. In recent years a steady increase in the number of fluorinated organic molecules reaching commercial status as crop protection products and pharmaceutical drugs has been observed: This is mainly due to the fact that selectively fluorinated compounds can exhibit dramatically improved poten-cy when compared to the non-fluorinated analogues. The incorporation of fluorine into a biologically active compound alters the electronic, lipophilic and steric parameters and can critically increase the intrinsic activity, the chemical and metabolic stability, and the bioavailability. This presentation will give a brief summary on the recent research progress of organofluorine chemistry in China.

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BS-03-01

DNA Origami Based Nanocarriers For Delivery, Targeting and Gene Silencing

Mustafa Culha, Pinar Akkus, and Cansu Umran Tas

Department of Genetics and Bioengineering, Faculty of Engineering, Yeditepe University, Ataşehir, Istanbul 34755, Turkey

The development of effective drug carriers is intensively investigated to increase the treatment efficiency and to decrease possible side effects of a drug. The use of variety of nanostructured materials such as gold nanoparticles (AuNPs) and CNTs is perused due to their several unique physicochemical properties. However, the use of these materials for such a goal is in question due to the toxicity and biocompatibility concerns. In order to avoid these possible problems, biomacromolecules can be used for drug delivery applications as effective drug carrier systems. Among biomacromolecules, DNA offers a unique opportunity because Watson-Crick based paring can be utilized to generate variety of novel structures. In this study, DNA-origami based nanostructures as drug carriers were constructed. A therapeutic drug, doxorubicin, and targeting agents, folic acid and lactose, chemically bound to the oligonucleotides complementary to the sticky ends of the DNA-origami structure. Then, the modified oligonucleotides were hybridized with the sticky ends protruding from the DNA-origami structure. For gene silencing, a morpholino complementary to the mRNA of the target gene was embedded into the origami structure. As the origami structure was degraded in the cytosol, the morpholino resisting the enzymatic degradation was released. The efficiency of the Origami structures was tested on MDA_MB_231 (Breast Adenocarcinoma Cells), and A549 (Human lung adenocarcinoma epithelial cells). It was found that the DNA-Origami carriers were effective to deliver the cargo into the cancer cells. The results indicate that the DNA-origami structures can be used as promising nanocarriers for delivery and targeting.

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Development of New Catalytic System for Coupling of Alkynes with Grignard Reagents using Zirconocene

Tamotsu Takahashi

Catalysis Research Center, Hokkaido University, Kita 21, Nishi 10, Sapporo 001-0021, Japan

We have developed a stoichiometric reaction as shown below. Very recently we could change this stoi-chiometric reaction to catalytic. In this lecture I will report our successful result for the development of a catalytic reaction for the coupling of alkynes with Ethyl Grignard from the stoichiometric reaction.

Development of New Catalytic System for Coupling of Alkynes with Grignard Reagents using Zirconocene

Tamotsu Takahashi Catalysis Research Center, Hokkaido University, Kita 21, Nishi 10, Sapporo 001-0021, Japan We have developed a stoichiometric reaction as shown below. Very recently we could change this stoichiometric reaction to catalytic. In this lecture I will report our successful result for the development of a catalytic reaction for the coupling of alkynes with Ethyl Grignard from the stoichiometric reaction.

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BS-03-04

Functional components for supramolecular architecture: cucurbiturils, multi-farenes and bambusurils

Ehud Keinan

Schulich Faculty of Chemistry, Technion –Israel Institute of Technology, Haifa 32000, Israel [email protected]

The host-guest chemistry of cucurbiturils and their analogs can be exploited for the development of specific chemical sensors, metal binders and for the construction of new molecular architectures. For example, switchable cucurbituril beacons were found useful for measurement of binding constants and monitoring of biocatalytic reactions. A new binding mode that is relevant cucurbiturils was discovered, suggesting n-π* interactions between organic azide groups and the carbonyl functions of the cucurbi-turil portal.

Multifarenes are a new macrocycles, which comprise alternating building blocks, such as phenols and cyclic thioureas. These cavitands are conveniently prepared by three complementary synthetic ap-proaches that provide modularity and scalability. In addition to metal-ion coordination, these cavitands show increased flexibility with increasing ring size, offering opportunities for induced fit to guest mol-ecules. More rigid multifarenes exhibiting unique binding properties, which could be relevant to the inclusion of aromatic amino acids, were prepared by using aromatic polycyclic building blocks.

The bambusurils are unique anion binding molecules. We replaced their known urea functions by thiourea and guanidine units. Their dual function is exhibited by binding metal ions and metal surfaces at their portals while their interior acts as an anion receptor with high affinity and selectivity for various anions in both organic solvents and aqueous media.

(1) Sinha, M.K.; Reany, O.; Parvari, G.; Karmakar, A.; Keinan, E. Chem. Eur. J. 2010, 16, 9056.(2) Parvari, G.; Reany, O.; Keinan, E. Isr. J. Chem. 2011, 51, 646.(3) Sinha, M.K.; Reany, O.; Yefet, M.; Botoshansky, M.; Keinan, E. Chem. Eur. J. 2012, 18, 5589.(4) Parvari, G.; Annamalai, S.; Borovoi, I.; Chechik, H.; Botoshansky, M.; Pappo, D.; Keinan, E.Chem. Commun. 2014, 50, 2494.(5) Singh, M. Parvari, G., Botoshansky, M., Keinan, E., Reany, O. Eur. J. Org. Chem. 2014, 933.(6) Singh, M., Solel, E., Keinan, E., Reany, O. Submitted to Chem Eur. J. 2014.

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O-A1-01-02

INDOOR PSYCHOTROPIC SUBSTANCES IN ROME: LEVELS AND BEHAVIORS

C. Balducci, P. Romagnoli, M. Perilli, A. Cecinato

CNR Institute of Atmospheric Pollution Research (CNR-IIA),00015, Monterotondo Stazione RM, ItalyPresenting author: [email protected]

Among the thousands of compounds comprised in the organic fraction of airborne particulate, a special group is formed by psychotropic substances. Nicotine and caffeine, as licit drugs, were identified in aerosols since long time, whereas more recent is the discovery of illicit drugs occurrence. Cocaine and cannabinoids were first detected in the atmosphere of Rome and Taranto in 2006. Ever since, many studies have been conducted in Italy, and the illicit drugs presence in the open atmosphere has been confirmed in several regions of the world. As for aquatic systems, illicit drugs have been definitively indicated as new contaminants, and potential harmful effects on the environment have been listed. By contrast, till now this facet has been neglected in the atmospheric compartment because of the low concentrations usually detected for psychotropic substances. Nevertheless, illicit substances are often abused indoors. Noticeably, the phenomenon of toxicant intake through “passive consumption” or “passive ingestion” is recognized as capable of leading to adverse effects in the case of heavily contaminated environments [1]. The first investigation aimed at assessing the pathways followed by drugs of abuse in indoor environments was conducted between 2011 and 2013. Atmospheric particulate samples were collected in Rome at homes and schools plus one office and one coffee bar [2]. The drug levels indoors and the respective relationships with outdoor atmosphere were investigated. The monitoring procedure optimized allowed to determine cocaine and cannabinoids, as well as the particulate fractions of nicotine and caffeine. Although covering different year seasons and living place types, this investigation can be considered as preliminary to further investigations. In fact, all sites were not frequented by consumers, especially with regards to illicit substances, and only one home hosted cigarette smokers. However, the results show that both licit and illicit psychotropic substances affect all indoor environments, where citizens spend most of their life. The high levels detected randomly indoors, combined with the fact that psychotropic substances were more abundant at our target sites than at regional stations, suggest that these substances can have an environmental relevance. Anyway, more extensive studies are needed at new site categories to estimate the exposure of citizens (or particular classes of citizens) to drugs. Besides, the indoor drugs behavior was different from both outdoor drugs and regulated toxicants. As an example, the Δ9-tetrahydrocannabinol (main psychotropic constituent of the cannabis) seemed to decompose easily at the open air, while it appeared much more persistent indoors.

1. F. De Giorgio, S. Strano Rossi, J. Rainio, M. Chiarotti, Int. J. Legal. Med. 118, 310 (2004). 2. A. Cecinato, C. Balducci, P. Romagnoli, M. Perilli, Environ. Sci. Pollut. Res. Article in Press DOI

10.1007/s11356-014-2839-2.

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O-A1-01-03

PARTICLE-SIZE DISTRIBUTION OF POLYBROMINATED DIPHENYL ETHERS (PBDES) IN THE URBAN AGGLOMERATION OF THESSALONIKI,

NORTHERN GREECE

Besis1, E. Botsaropoulou1, D. Voutsa1, C. Samara1

1Environmental Pollution Control Laboratory, Department of Chemistry, Aristotle University of Thes-saloniki, GR-54124 Thessaloniki Greece


Particle-size distribution (<0.49, 0.49-0.97, 0.97-1.5, 1.5-3.0, 3.0-7.2 and >7.2μm) of Polybrominated Diphenyl Ethers (PBDEs) was measured during the cold and the warm period of the year 2013 using a cascade impactor at two sites in the urban agglomeration of Thessaloniki, northern Greece (traffic and urban background).

Mean aggregate concentrations (sum of six fractions) of the sum of 12 PBDE congeners (∑12PBDE) were 20.3 pg m-3 and 2.1 pg m-3 for the traffic and the urban background site, respectively in the cold period. The corresponding concentrations in the warm period were 27.1 pg m-3 and 2.4 pg m-3, respec-tively. Higher concentrations of PBDEs were observed in warm seasons at both sites.

The most abundant PBDE congeners were BDE-47 and BDE-99. At both sampling sites, more than 58% of ∑12PBDE was associated with particles of <0.49 μm in diameter. Our results imply that particu-late PBDEs may have long atmospheric residence time and they may be capable of reaching the deeper parts of the human respiratory system.

Acknowledgements

This research has been co-financed by the European Union (European Social Fund – ESF) and the Greek Ministry of Education through the Research Funding Program THALES (Project code/Title: MIS 377304/”Bioactivity of airborne particulates in relation with their size, morphology and chemical com-position”. We thank Dr. Apostolos Kelesis, Municipality of Thessaloniki, for providing meteorological data and on-site support.

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O-A1-01-04

HUMAN METABOLITES OF PHARMACEUTICALS – DO THEY EMERGE AGAIN IN THE AQUATIC ENVIRONMENT AS POTENTIAL

HAZARDOUS CONTAMINANTS ?

Despina Athanasiadou1, Dr. V.Linnemann1, Prof. J. Pinnekamp1

1Institute of Environmental Engineering, Environmental Analytical Laboratory, RWTH Aachen University, Germany


Emerging pollutants are increasingly detected in aqueous environmental samples and among them human pharmaceuticals and related compounds consist a large category with many diverse groups, due to the advances in organic synthesis and their intensive use. They can reach the environment through excretion in the original chemical structure or as metabolites and through improper elimination or disposal [2] additionally as transformation products. Since several years scientists worldwide have performed significant research regarding occurrence, fate and health effects of the parent drugs [4,3]. However, very little attention has been given to the potential contribution that human metabolites excreted into the environment or microbial metabolites formed during environmental biodegradation of pharmaceutical residues “bio-transformation products” - may have. The scarcity of available environmental data on such substances can be attributed to the difficulty in analyzing trace amounts of previously unknown compounds in complex sample matrices without reference materials.Similar degradation reactions like those in human metabolism follow in the environment and in biological wastewater treatment by microorganisms as well and cause the emergence of these substances. In this context, the present work indicates how human metabolites are rebuilt after biological treatment (figure 1 and 2) as emerging compounds with potential hazardous impact on the aquatic organisms.Table 1: Metabolization and Transformation pathways of Metoprolol

Investigations on aqueous environmental samples have been performed via high performance liquid chromatography (HPLC) followed by high resolution mass spectrometric (MSn) detection combined with a sample preparation procedure, in order to designate the exact molecular mass and thus to facilitate biodegradation

products identification in environmental samples of 3 β-Blockers. The present study illustrates the results of the one of them – Metoprolol – and indicates the re-formation of Metoprolol human metabolites along together with other new biotransformation products after biological treatment. Furthermore, residues of the identified compounds were detected in wastewater effluent samples in low concentrations ranging from the ng/L up to the μg/L level.Moreover the parent compound (Metoprolol) was examined with regard on its toxicological significance via established ecotoxicological tests. On the top of that, the mixture toxicity of it and its bio-products was estimated based on the determined environmental concentrations and two different concepts that are in use for the prediction of mixture toxicity: concentration addition and independent action [1]. The ultimate aim of this study is to contribute to this challenging task of enhancing the available data on the fate, behavior, and ecotoxicity of pharmaceutical metabolites and emerging transformation products in the environment.

References

1. Cleuvers M.: Initial risk assessment for three β-blockers found in the aquatic environment. Volume 59, Issue 2, April 2005, Pages 199–205 DOI: 10.1016/j.chemosphere.2004.11.090

2. Corcoran J.; Winter M.J.; Tyler C.R.: Pharmaceuticals in the aquatic environment: A critical review of the evidence for health effects in fish. Critical reviews in toxicology. Volume 40, Issue 4, Pages 287-304, Published April 2010

3. Daughton CG.: Emerging pollutants, and communicating the science of environmental chemistry and mass spectrometry: Pharmaceuticals in the environment. Journal of the American society for mass spectrometry. Volume 12, Issue 10, Pages 1067-1076, Published October 2001

4. Kümmerer K.: The presence of pharmaceuticals in the environment due to human use - present knowledge and future challenges. Journal of environmental management. Volume 90, Issue 8, Pages 2354-2366, Published June 2009

HUMAN METABOLITES OF PHARMACEUTICALS – DO THEY EMERGE AGAIN IN THE AQUATIC ENVIRONMENT AS POTENTIAL HAZARDOUS

CONTAMINANTS ?

Despina Athanasiadou1, Dr. V.Linnemann1, Prof. J. Pinnekamp1 1Institute of Environmental Engineering, Environmental Analytical Laboratory, RWTH

Aachen University, Germany Presenting author: [email protected]

Emerging pollutants are increasingly detected in aqueous environmental samples and among them human pharmaceuticals and related compounds consist a large category with many diverse groups, due to the advances in organic synthesis and their intensive use. They can reach the environment through excretion in the original chemical structure or as metabolites and through improper elimination or disposal [2] additionally as transformation products. Since several years scientists worldwide have performed significant research regarding occurrence, fate and health effects of the parent drugs [4,3]. However, very little attention has been given to the potential contribution that human metabolites excreted into the environment or microbial metabolites formed during environmental biodegradation of pharmaceutical residues "bio-transformation products" - may have. The scarcity of available environmental data on such substances can be attributed to the difficulty in analyzing trace amounts of previously unknown compounds in complex sample matrices without reference materials.

Similar degradation reactions like those in human metabolism follow in the environment and in biological wastewater treatment by microorganisms as well and cause the emergence of these substances. In this context, the present work indicates how human metabolites are rebuilt after biological treatment (figure 1 and 2) as emerging compounds with potential hazardous impact on the aquatic organisms. Table 1: Metabolization and Transformation pathways of Metoprolol

Figure 1: Human metabolization of Metoprolol

Figure 2: Transformation of Metoprolol in the biological wastewater treatment

Investigations on aqueous environmental samples have been performed via high performance liquid chromatography (HPLC) followed by high resolution mass spectrometric (MSn) detection combined with a sample preparation procedure, in order to designate the exact molecular mass and thus to facilitate biodegradation products identification in environmental samples of 3 β-Blockers. The present study illustrates the results of the one of them –

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O-A1-01-05

DARK FORMATION OF ·OH RADICALS IN ANOXIC LAKE WATER

D. Vione, M. Minella, E. De Laurentiis, V. Maurino, C. Minero

Dipartimento di Chimica, Università di Torino, Via Pietro Giuria 5, 10125 Torino, ItalyPresenting author: [email protected]

The hydroxyl radical (·OH) is a highly reactive transient, causing the degradation of most dissolved organic and inorganic substrates [1] and affecting the cycling of carbon and other nutrients. It is formed photochemically in surface waters, by irradiation of photosensitisers such as chromophoric dissolved organic matter (CDOM), nitrite and nitrate [2-3]. Here we report for the first time that ·OH can also be produced in the dark by aeration of anoxic lake water. Many lakes located in temperate environments are stratified during summer, as the warmer and oxygenated surface layer (epilimnion) floats above the colder and often anoxic deep water (hypolimnion). Lake overturn in late summer – early autumn ensures oxygenation of the water column. Dark formation of ·OH was assessed in anoxic water (taken from the hypolimnion during summer stratification) after exposure to the atmosphere, using terephtalic acid (TA) transformation into hydroxyterephtalic acid (TAOH) as ·OH probe reaction. The possible ·OH formation pathways are Fenton and Fenton-like reactions, induced by FeII and most notably by hydroquinones or semiquinone radicals [4].

The importance of the process can be assessed by comparing dark ·OH formation with photochemical processes taking place in the sunlit epilimnion. The cumulated ·OH production of hypolimnion samples exposed to air for a few hours is equivalent to about one-half of the year-round photochemical ·OH generation in the epilimnion. The dark reaction, here described for the first time, is thus a new environmental process that could be very important in the yearly ·OH budget of lake environments. It could play a key role in the self-depollution potential of the lakes and in carbon biogeochemical cycles. This is an exciting new discovery that could deeply modify the current understanding of the processes taking place in lake water and leading to the transformation of natural organic matter and of xenobiotics.

Fig. 1. Time trend of TAOH formed from 1 mM TA in hypolimnion samples exposed to the atmosphere. Insert: highest TAOH concentration reached in the experiments (Surf: surface samples; B1, B2: anoxic samples from the hypolimnion). AV: Lake Avigliana; CA: Lake Candia; SdS: Lake Sottano della Sella; VI: Lake Viverone.

References1. G.V. Buxton, C.L. Greenstock, W.P. Helman, A.B. Ross, J. Phys. Chem. Ref. Data 17, 513 (1988).2. J.V. Goldstone, M.J. Pullin, S. Bertilsson, B.M. Voelker, Environ. Sci. Technol. 36, 364 (2002).3. M.A. Tarr, W. Wang, T.S. Bianchi, E. Engelhaupt, Wat. Res. 35, 3688 (2001).4. S.E. Page, M. Sander, W.A. Arnold, K. McNeill, Environ. Sci. Technol. 46, 1590 (2012).

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O-A1-02-02

IMPACTS OF THE ORIGIN AND THE TREATMENT OF ORGANIC WASTE RECYCLED IN AGRICULTURE ON THE FATE AND THE

AVAILABILITY OF ANTIBIOTICS IN CULTIVATED SOILS

A. Goulas1, V. Bergheaud1, S. Fehri1, V. Dumény1, S. Nélieu2, M. Deschamps1, S. Houot1

C.S. Haudin1, P. Benoit1.1UMR 1091 INRA-AgroParisTech Environnement and Arable Crops,

78850, Thiverval-Grignon, France2UR 251 INRA Physicochimie et Ecotoxicologie des Sols d’Agrosystèmes Contaminés,

78000, Versailles, France Presenting author: [email protected]

Veterinary and human antibiotics are found in manures and biosolids used in agriculture as organic amendments. The repeated introduction in cultivated soils of small amounts of antibiotics and by-products with organic waste may have an impact on microbial functions and communities, in particular by contributing to the acquisition of resistance against antibiotics. The effects of antibiotics on microorganisms are in theory linked to the bioavailable fraction of compounds in soil, which could be influenced by the treatment of organic waste (e.g. composting). The objective of this study was to follow the evolution of the (bio)available fraction of two antibiotics (sulfamethoxazole, SMX; ciprofloxacin, CIP) in soil after the application of two types of organic waste (compost of sewage sludge with green waste, bovine manure) currently used on the long-term field experiment QualiAgro (INRA–Veolia partnership 1998–2013). Soft chemical extractants were selected for this purpose and compared.

Mixtures of soil (5 g dry mass, DM) and organic waste (0.15 g DM of either compost or manure) initially enriched with of a 14C-labelled antibiotic (14C-SMX: 0.74 mg.kg-1 DM; 14C-CIP: 4.97 mg.kg-1 DM) were incubated under controlled aerated conditions for 28 days. The mineralization of the 14C-antibiotic and the organic matter was followed over the incubation period. At 0, 7 and 28 days, the (bio)availability of each 14C-antibiotic in mixtures was assessed through a soft chemical extraction with different aqueous solutions. A second extraction with an acetonitrile/water mixture was performed and solid residues were then dried and burnt in order to quantify the fraction of non-extractable 14C-SMX and 14C-CIP residues.

The fractions of extracted 14C-antibiotic residues differed according to the type of aqueous solution in both types of organic waste-soil mixtures. The availability of 14C-SMX decreased rapidly over time. The availability of 14C-CIP was very low at the start of the incubation but it slightly increased at 7 days for the manure treatment. Regardless of the choice of the aqueous solution, significant amounts of non-extractable residues (NER) were formed after 28 days. The choice of the aqueous solution impacted more the relative proportions of 14C-antibiotic residues extracted by the aqueous solutions and the acetonitrile/water mixture than the amounts of NER. Less than 1% of the initially added 14C-CIP was mineralized after 28 days, against 2-3% for 14C-SMX. The mineralization of organic matter was more important with manure. We hypothesize that the stimulation of microbial activity may explain the greater formation of NER of 14C-SMX residues for the manure treatment.

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O-A1-02-03

ELECTROCHEMICAL AND QUANTUM CHEMICAL STUDIES ON NITROBENZANTHRONES, EXTREMELY MUTAGENIC ENVIRONMENTAL

POLLUTANTS

I. Linhart1, A. Králík1, J. Ludvík2, M. Himl1

1 Department of Organic Chemistry, Faculty of Chemical Technology, Institute of Chemical Technology, Prague, Technická 1905, CZ-166 28 Prague,Czech Republic

2 J. Heyrovský Institute of Physical Chemistry, Dolejškova 3, CZ-182 00 Prague, Czech RepublicPresenting author: [email protected]

Nitrobenzanthrones (NBAs) are important environmental pollutants emitted mainly from diesel engines. Differences by 5 orders of magnitude were observed in the mutagenicity of NBA isomers, the most mutagenic one being 3-NBA [1]. Mutagenicity of NBAs was found to be closely linked to their reductive biotransformation leading to arylnitrenium ions, which are capable of binding to the DNA [2].Electrochemical analysis in dry DMF showed that 3-NBA undergoes two subsequent fully reversible one-electron reduction steps at E1 = - 0.64 V and E2 = - 0.95 V. In contrast, in the case of 2-NBA the first reversible one-electron reduction at E1 = - 0.88 V was followed by an irreversible three-electron process at E2 = - 1.38 V. These results indicate a resonance stabilisation of the dianion derived from 3-NBA but not that derived from 2-NBA. Analogically, 3-NBA was much more readily reduced than its 2-isomer under the conditions of catalytic hydrogenation on Pd/C.

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O

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O

O

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Figure 1: Electrochemical reduction of 3-nitrobenzanthrone

Quantum chemical calculations (DFT, PBE1PBE/6-31G) of the potential energies for dianions of 1-, 2-, 3-, 9- and 11-NBA showed that these energies closely correlate (R = 0.989) with published values of mutagenicity in Salmonella typhimurium1 except for 11-NBA, which is virtually non-mutagenic. Although dianions formed by two-electron reduction of NBAs can arise only in aprotic solvents and certainly not in vivo, their formation by electrochemical processes as well as their resonance stabilisation might be indirectly linked to the formation and stability of benzanthronyl-nitrenium ions and to the mutagenic and carcinogenic potential of NBA isomers. Acknowledgement. This study was supported from the institutional sources of ICT Prague.

References1. T. Enya, H. Suzuki, T. Watanabe, Y. Hirayama and Y Hisamatsu. Environ. Sci. Technol. 31, 2772

(1997).2. V. M. Arlt, Mutagenesis 20, 399 (2005).

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O-A1-02-04

DEVELOPMENT OF GREEN ALTERNATIVES TO PHTHALATE PLASTICIZERS

H.C. Erythropel1, T. Brown1, S. Shipley1, J.A. Nicell2, M. Maric, R.L1. Leask1

1McGill University, Dept. of Chemical Engineering, Montreal, Canada2McGill University, Dept. of Civil Engineering and Applied Mechanics, Montreal, Canada


Plasticizers are widely used additives to hard and brittle polymers such as poly(vinyl chloride) (PVC). Plasticizers are only loosely bound to the polymer matrix and therefore leach out over time, ending up in the environment. One of the most used plasticizers is di(2-ethylhexyl phthalate) (DEHP), yet it has come under scrutiny in the past due to its slow biodegradation and subsequent build-up in the environment. Moreover, it produces problematic breakdown products, specially its monoester MEHP. This has led to efforts to design new, green plasticizers.

This project investigated compounds with the potential to replace phthalates. These were diester compounds based on maleic and succinic acid, esterified with straight-carbon alcohols. These were then tested for their plasticizer properties in rigid unplasticized PVC, as well as for their biodegradation rates when the pure compounds were exposed to the common soil bacterium Rhodococcus rhodocrous. In cross-disciplinary cooperation, these new green compounds are also being tested for toxicity and androgenic activity.

Plasticizing properties of these blends were assessed using DSC, mechanical testing, as well as rheology. Results indicate that both groups of green plasticizers seem suitable candidates for replacing DEHP. Biodegradation experiments showed that a substantial difference in hydrolysis rates of one ester bond between the cis-structured maleates, which structurally resemble DEHP, and the saturated succinate compounds [1]. While hydrolysis rates for the maleates were slow, the succinate compounds were removed from the broth in a matter of days [2]. This could help to explain the slow hydrolysis of DEHP in the environment. However, the maleate compounds could be rendered more biodegradable by using straight carbon chains.

Combining the results of these tests, we have shown the dramatic influence of the structure of these diester compounds on biodegradation rates, as well as demonstrated ways of rendering the maleate compounds more biodegradable, while maintaining good plasticizer properties.

References1. H.C. Erythropel et al., Chemosphere 86 (8) (2012).2. H.C. Erythropel et al., Chemosphere 91 (3) (2013).

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O-A1-02-05

THE OCCURRENCE AND REMOVAL OF CYTOSTATICS CYCLOPHOS-PHAMIDE AND IFOSFAMIDE IN WASTEWATERS

M. Česen1,2, T. Kosjek1,2, B. Kompare3, E. Heath.1,2

1Jozef Stefan Institute, 1000, Ljubljana, Slovenia2Jozef Stefan International Postgraduate School, 1000, Ljubljana, Slovenia

3Faculty of Civil and Geodetic Engineering, University of Ljubljana, Ljubljana, SloveniaPresenting author: [email protected]

The trend towards the increasing use of chemotherapy among cancer patients raises questions concern-ing the presence of cytostatic drug residues in the environment and the impact they have on ecosystems. In the present study, we quantify cyclophosphamide (CP) and ifosfamide (IF) in hospital wastewaters, where both drugs are routinely administered to treat various types of cancers. The quality of our results regarding our analytical methodology was confirmed by an interlaboratory study, the first such study of its kind involving cytostatic residues in aqueous samples. The results will be presented at the EuCheMS separately. This paper reports the detection of CP and IF in Slovene hospital effluents in concentrations from 0.01 - 12.1 μg L-1 and 0.13 - 10.5 μg L-1, respectively. Further, we investigated the biodegradation of CP and IF (initial concentration 10 µg L-1) in a laboratory scale flow-through moving bed bioreac-tors with attached-growth biomass on Mutag BioChip™ carriers. The average removal efficiencies of CP and IF during the first month of a five month sampling campaign were 52 ± 8 % and 26 ± 6 %, respectively. To achieve higher removal efficiencies, the following advanced oxidation processes were investigated: UV, ozone, UV/ozone, UV/hydrogen peroxide (H2O2), ozone/H2O2 and UV/ozone/H2O2. The optimal conditions for removal were determined regarding the duration of the UV treatment and/or ozonation process (20 to 120 mins) and the amount of added H2O2 (20 mg L-1 – 5000 mg L-1). The most effective treatment was UV/ozone/H2O2 (5 g L-1) treatment, which gave removal efficiencies of 79 % (CP) and 72 % (IF). The results showed that degradation fits the pseudo-first order kinetic model for both compounds with rate constants at 8.9 min-1 and 6.3 min-1 and half-lives (t½) of 18.8 min and 26.3 min for CP and IF, respectively. Actual hospital wastewater was also included in the study, where chemical analysis had revealed concentrations of CP and IF at 5.34 μg L-1 and 6.83 μg L-1, respectively. It was confirmed that the degradation kinetics followed the same order resulting in similar rate con-stants (CP: 9.2 min-1 and IF: 8.2 min-1) and t½ (CP: 18.0 min, IF: 20.3 min). These results indicate the potential of using UV/ozone/H2O2 for removing both compounds from wastewaters. Future work will include coupling the attached-growth biomass biological treatment with selected AOP treatment (UV/ozone/H2O2) as pre- and post-treatment. Further, ecotoxicity will be evaluated in all treated samples.

Acknowledgements: We would like to thank Institute of Oncology Ljubljana, Slovenia and University Medical Centre Ljubljana, Slovenia for their collaboration.

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O-A1-02-06

DIFFERENT COMPOSITIONS OF PHARMACEUTICALS IN DUTCH AND BELGIAN RIVERS EXPLAINED BY CONSUMPTION PATTERNS

AND TREATMENT EFFICIENCY

Thomas L. ter Laak1,2 Pascal J.F. Kooij1 Harry Tolkamp1,3 and Jan Hofman1

1KWR Watercycle Research Institute, P.O. Box 1072, 3430 BB, Nieuwegein, the Netherlands2Department of Environmental Technology, Wageningen University, P.O. Box 8129, 6700 EV Wagen-

ingen, the Netherlands3Roer en Overmaas Regional Water Authority, P.O. Box 185 6130 AD Sittard, The Netherlands

E: [email protected]; [email protected]

AbstractIn the current study 45 pharmaceuticals and 18 transformation products were studied in the river Meuse at the Belgian-Dutch border and four tributaries of the river Meuse in the southern part of the Nether-lands. The tributaries originate from Belgian, Dutch and mixed Dutch and Belgian catchments. In total, 24 pharmaceuticals and 13 transformation products were observed in samples of river water collected from these rivers. Observed summed concentrations of pharmaceuticals and transformation products in river water ranged from 3.5 to 37.8 µg/L. Metformin and its transformation product guanylurea contributed with 53 to 80 % to this concentration, illustrating its importance on a mass basis. Data on the flow rate of different rivers and demographics of the catchments enabled us to calculate daily per capita loads of pharmaceuticals and transformation products. These loads were linked to sales data of pharmaceuticals in the catchment. Simple mass balance modelling accounting for human excretion and removal by sewage treatment plants revealed that sales could predict actual loads within a factor three for most pharmaceuticals. Rivers that originated from Belgian and mixed Dutch and Belgian catch-ments revealed significantly higher per capita loads of pharmaceuticals (16.0 ±2.3 and 15.7 ±2.1 mg/inhabitant/day, respectively) than the Dutch catchment (8.7 ±1.8 mg/inhabitant/day). Furthermore, the guanylurea /metformin ratio was significantly lower in waters originating from Belgium (and France) than in those from the Netherlands, illustrating that sewage treatment in Belgium is less efficient in transforming metformin into guanylurea. In summary, the current study shows that consumption based modelling is suitable to predict environmental loads and concentrations. Furthermore, different con-sumption patterns and treatment efficiency are clearly reflected in the occurrence and loads of pharma-

ceuticals in regional rivers.

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O-A1-03-02

QUANTIFICATION OF MICROPOLLUTANT DEGRADATION IN THE RIVERBANK USING A LC-HRMS/MS SCREENING METHOD

J. Rothardt1, D. Radny2, H. P. Singer1, and J. Hollender1

1Department of Environmental Chemistry, Swiss Federal Institute of Aquatic Science and Technology EAWAG, 8600 Dübendorf, Switzerland

2Department Water Resources and Drinking Water, Swiss Federal Institute of Aquatic Science and Technology EAWAG, 8600 Dübendorf, Switzerland


Riverbank filtration (RBF) is a commonly applied method to produce high quality drinking water in Europe [1]. The increasing load of organic micropollutants (MP) cause considerable conflicts with regard to maintaining drinking water quality criterias. Thus, contamination of shallow groundwater is a substantial concern, especially in effluent-dominated streams and underlines the need for an improved understanding of fate and transport of organic micropollutants [2]. Surface-water to shallow-groundwater, to drinking water well transport of a broad setup of 528 emerging contaminants (log Dow (pH 7) between -5.7 and +5.6) was investigated at three different river sites in the western part of Switzerland. The obtained samples were spiked with 163 internal standards (IS) and enriched by offline solid phase extraction using a multi-layer extraction cartridge with five different adsorber materials to enable the enrichment of micropollutants with a broad spectra of chemical-and physical properties. After elution and evaporation the sample extracts were analyzed by liquid chromatography coupled to a high resolution mass spectrometry (Q-Exactive) operated with an electrospray ionization probe [3]. Overall, 134 of the 526 MPs were detected in the sampled surface, ground, and drinking water well samples, including 70 pharmaceuticals (including 14 metabolites), 4 anaesthetic (including 2 metabolites), 32 pesticides (including 11 metabolites), 3 biocides (including 1 metabolite), 9 per-and polyfluorinated compounds, 5 food additives, 3 anti-corrosion agents (including 1 metabolite), 3 industrial chemicals, 3 personal care products, one additive and one tracer above the limit of quantification (LOQ). The LOQ varied only slightly for the two different surface waters, where additional spiking was carried out, i.e. the LOQ was below 10 ng/L for 80% and below 1 ng/L for 20% of the compounds. Riverbank filtration with varying MP removal potential ranging from 22, over 41, to 60% of the detected compounds, was observed at the three sampled sites with different retention times in the groundwater body to the sampling wells. Out of the 134 detected MPs, concentrations of 37, 40, and 42 MPs, respectively, were removed during RBF at the three investigated sites. 24 compounds were present in all analysed samples, whereof no, or only slight elimination was observed for sulfamethoxazole, lamotrigin, and carbamazepine. However, the observed MP removal cannot solely be attributed to biodegradation or retardation. First results of numerical flow and transport modeling - as part of this ongoing interdisciplinary investigation - indicate that dilution with other groundwater components need to be considered.

References

1. Ray, C., Clean Technol. Environ. Policy, 10, 223 (2008).2. Storck, F.R., Schmidt C.K., Lange F.T. et al., J. Am. Water Works Asso. 104, 35 (2012).3. Vogler, B., Masterthesis in EAWAG, Environmental Chemistry. (2013).

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O-A1-03-03

SUSPECT AND NON-TARGET SCREENING OF ORGANIC MICROPOLLUTANTS IN WASTEWATER THROUGH THE DEVELOPMENT

OF A LC-HRMS BASED WORKFLOW

P. Gago-Ferrero1,*, A.A. Bletsou1,ª, R. Aalizadeh,1 N.S. Thomaidis.1

1Laboratory of Analytical Chemistry, Department of Chemistry, University of Athens, Panepistimiopolis Zographou, 15771 Athens, Greece

ªBoth authors contributed equally to this workPresenting author: [email protected]

A large number of organic contaminants and related transformation products (TPs) are present in wastewaters. Target analysis only allows the detection of a very small fraction of these substances, due to the inability to obtain standards for all that substances and the ignorance of the existence of many of them. Recent advances in high resolution mass spectrometry (HRMS) have opened up new windows of opportunity in the field of complex samples analysis [1]. The application of suspect and non-target screening methods allows the tentative identification of a much larger amount of pollutants and focus efforts on the most relevance substances in terms of environmental concern. However, a balance between extensive target analysis and screening methods is needed.The aim of the present work is the development and application of an integrated workflow based on liquid chromatography coupled to a quadrupole-time-of-flight mass spectrometer (LC–QToF-MS) to detect suspected and formerly unknown organic contaminants in wastewater.Suspect screening was carried out through the set-up of a large in-house data base including the molecular formula of more than 7000 relevant organic pollutants and TPs (which were not present in our existing target methods). The tentative identification of these compounds was based in the evaluation of criteria such as blank signal presence, mass accuracy or isotopic pattern. Moreover, the chromatographic retention time plausibility (using prediction models) and MS spectra comparisons were also considered. According with the aforementioned criteria, few suspect compounds were tentatively identified in wastewater samples from the wastewater treatment plant (WWTP) of Athens, the largest in Greece.Full identification of unknown compounds is often difficult and there is no guarantee of a successful outcome. After optimizing the peak peaking procedure using molecular features algorithm, relevant peaks were selected based on the intensity and the presence of distinctive isotopic patterns (the most relevant substances with reasonable identification possibilities). For the selected peaks the most plausible molecular formula(s) were determined by applying thresholds of mass accuracy, isotopic pattern and even commercial importance through the use of the Seven Golden Rules software [1]. A deep evaluation of the MS spectra was performed for these peaks, using both data bases (e.g. mass bank) and in silico fragmentation software (e.g. Metfrag) to find candidates. Chromatographic retention time prediction models were also applied to assess the plausibility of the candidates. This approach allows the obtaining of plausible candidates for most of the selected peaks and the tentative identification for some of them in the evaluated samples.

References[1] E. Schymanski et al., Environ. Sci. Technol 48, 1811 (2014).[2] T. Kind and O. Fiehn, BMC Bioinformatics 8, 105 (2007).Acknowledgment This project was implemented under the Operational Program «Education and Lifelong Learning» and funded by the European Union (European Social Fund) and National Resources – ARISTEIA 624 (TREMEPOL project).

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O-A1-03-04

ELECTROCHEMISTRY MASS SPECTROMETRY TO STUDY TRANS-FORMATION OF EMERGING CONTAMINANTS – SIMULATING CAR-

BAMAZEPINE TRANSFORMATION BY WHITE-ROT FUNGI

B. Seiwert1, C. Weidauer1, N. Golan-Rozen2, Y. Hadar2, B. Chefetz2, T. Reemtsma1

1Helmholtz Centre for Environmental Research - UFZ , 04318, Leipzig, Germany2Hebrew University of Jerusalem, 76100, Rehovot, Israel


The elucidation of transformation processes of contaminants in organisms, biological treatment sys-tems or the environment can be difficult as such systems consist of a multitude of (natural) compounds that may disturb the determination, recognition or identification of the transformation products (TP) of interest. The simulation of transformation reactions in the laboratory, starting with a pure solution of the test compound, makes the determination and recognition of TP a much easier task.

Electrochemistry coupled to liquid chromatography-mass spectrometry (EC-LC-MS) is a method to study oxidative transformation processes. If the electrochemical cell is coupled directly to LC-MS even reaction intermediates of limited stability may be detected. This helps to understand the mechanisms of transformation. EC-MS has been proposed as an instrumental approach to study phase I metabolism in higher organisms1. However electrochemical transformations with boron doped diamond electrodes (BDD electrode) are one-electron transitions and involve also OH radicals. The spectrum of TP is therefore more complex than that formed by microsomes or liver cell homogenates. White-rot fungi, however, provide a diversity of peroxidase enzymes that are capable of one-electron transfer.

Therefore we have studied whether EC-LC-MS is suited to simulate the oxidation of emerging pol-lutants by white-rot fungi. An LC-QTOF mass spectrometer provides separation of transformation products and identification by mass spectrometry without sample pretreatment. High resolution mass spectrometry provides molecular formula information whereas the product ion spectrum is a good basis for structure elucidation. Product ion spectra can be used to establish a library of possible TP to search for in the environment. When EC is coupled on-line to LC-MS also short-lived oxidation intermediates may be detected that help to understand the mechanism of transformation. Finally such a laboratory test systems is quite productive and allows studying the oxidative transformation of a large number of contaminants with limited experimental effort.

This concept was validated with carbamazepine (CBZ) as test compound, one of the frequently found pharmaceuticals in wastewater and the aquatic environment. Transformation by EC and by a white rot fungus (Pleurotus oestroatus) was compared. Both systems effectively transformed CBZ. The EC-LC-MS approach generated a large number of TP, their molecular formula and possible structure. Many of these TP were then also detected in culture of P. oestroatus grown with CBZ.

Laboratory test systems simulating environmental transformation processes can be favourably coupled to LC-MS to study transformation reactions of emerging contaminants and to elucidate their transfor-mation pathways in natural systems.

References

1. Jahn S, Karst U (2012) J. Chromatogr. A 1259, 16-49.

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O-A1-03-05

SIMULTANEOUS DETERMINATION OF CYANOTOXINS CYLINDROS-PERMOPSIN AND ANATOXIN-A IN WATER USING LC-MS/MS. OPTIMI-

ZATION OF EXTRACTION WITH EXPERIMENTAL DESIGN

Christophoros Christophoridis1, Aikaterini Droungou1, Sevasti-Kiriaki Zervou1, Theodoros Triantis1, Triantafyllos Kaloudis1 , Anastasia Hiskia1

1National Center for Scientific Research “Demokritos”, IAMPPNM, 15310 Athens, [email protected] (A. Hiskia)

Presenting author: Christophoros Christophoridis, [email protected]

Cyanobacteria are considered a rising environmental problem, since under favorable conditions, they can form extensive algal blooms and produce a wide range of cyanotoxins, which pose a significant risk to aquatic habitats and human health. Anatoxin-a (ANA) and Cylindrospermopsin (CYN), are two important cyanotoxins, often found in water bodies worldwide at increasing frequency and rising con-centrations. The objective of this study were: a) the development and validation of a chromatographic method for the simultaneous determination of CYN and ANA in water, using LC-MS/MS and b) the de-velopment and optimization of an extraction-preconcentration procedure using Solid Phase Extraction (SPE) and experimental design approach.

For the chromatographic separation of the compounds a reversed phase column was used (Atlantis T3 C18, 100x 2.1 mm, Waters) with an isocratic elution program - ACN (0.5% HCOOH) : H2O (0.5% HCOOH), 5% : 95%, ESI ionization and analysis time of 10 min. Quantification of CYN was based on the product ion 416 -> 194 m/z and verification on product ions 416 -> 274 and 336 m/z. For ANA, quantification was based on product ion 166->149 and verification on 166->131. Under those chro-matographic conditions retention times were: CYN Rt=2,7 min and ANA tR=3,6 min. ESI operating conditions were optimized for both compounds, and deuterated phenylalanine PHE-d5 was used as a surrogate standard. SPE cartridges with porous graphitic carbon, (Hyper PGC, 200mg,Thermo) were used for the extraction of CYN and ANA from water. The effect of various factors (initial sample pH, sample volume, ratio of MeOH:CH2Cl2 as eluent, %formic acid in eluent, eluent volume, % MeOH in initial sample) on the recovery was studied, using an experimental design approach. Initially, the three most important factors were selected using a Plackett-Burman design, in order to determine the parameters with the highest impact on the selected response (recovery). Subsequently a Central Com-posite Design (CCD) was used for the detailed analysis of the main effects and the interactions between factors.

The use of an organic mixture of MeOH:CH2Cl2 is improving recovery values for CYN, as opposed to the use of pure MeOH (increase from 5-8% to 105-135%). Further addition of formic acid on the elu-tion mixture is enhancing the recovery. Increasing sample pH (higher than 10), is significantly improv-ing the recovery of ANA from (1.2-5.4%) to (57.7-76.5%). The three factors with the highest impact on the response were initial sample pH, ratio of MeOH:CH2Cl2 as eluent and % formic acid in eluent. The significance of the proposed CCD model was acceptable and validated statistically by the F-test (Fisher variation ratio), while model terms were estimated based on probability (P-value) with 95% confidence level. The correlation of the experimental data with the theoretically predicted ones were generally high with R2>0.980.

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O-A1-04-02

ACTIVATED CARBON FOR ENHANCING MICROPOLLUTANTS REMOVAL IN UASB REACTOR

A. Butkovskyi1,2, L. Hernandez Leal2, H.H.M. Rijnaarts1, G. Zeeman1

1Wageningen University, P.O. Box 17, 6700 AA Wageningen, the Netherlands2 Wetsus, P.O. Box 1113, 8900 CC Leeuwarden, the Netherlands


Up-flow anaerobic sludge blanket (UASB) reactor is a core technology within “New Sanitation” concepts, aimed at maximal recovery of resources from source separated domestic wastewater streams [1]. An important drawback of the anaerobic process is a low removal of persistent micropollutants [2, 3]. Addition of activated carbon to the reactor may improve the environmental quality of the effluent. The aim of this study was to investigate the potential of activated carbon for enhancing micropollutants removal in a UASB reactor treating a mixture of black water and grey water.

UASB sludge was incubated in 100 ml Erlenmeyer flasks in a batch mode. To determine the impact of biomass growth on the adsorption capacity activated carbon (Norit, type C) was either incubated together with UASB sludge for 1, 3, 5 and 7 weeks prior to spiking or added directly after spiking of sludge with micropollutants. Blank samples were incubated without addition of activated carbon. Micropollutants (galaxolide, tonalide, triclosan, ibuprofen, diclofenac, gemfibrozil, estrone) were spiked to all batches 20 hours prior to sampling. Liquid phase, sludge and activated carbon were separated by centrifugation at 3750 rpm, followed by extraction of micropollutants from liquid and sludge and detection by GC-MS and LC-MS.

The removal of micropollutants from the liquid phase with both fresh and incubated carbon was higher than 98%. Removal of micropollutants was significantly lower in control experiments without carbon addition, ranging from 86% for tonalide to 6% for ibuprofen. It was mostly attributed to sorption, not to biodegradation. Removal of micropollutants from sludge exceeded 80% for all compounds, except for galaxolide and tonalide. Lower concentrations of the spiked micropollutants were observed in sludge samples with addition of the fresh carbon as compared to incubated carbon. The increased partitioning of micropollutants towards the fresh carbon is a possible explanation. However methodological biases related to improper separation of carbon from sludge cannot be excluded.

The obtained results indicate that addition of activated carbon to sludge phase of a UASB reactor can result in significant adsorption of micropollutants to the activated carbon. Thus, improved quality of the liquid effluent and organic sludge of a UASB reactor treating a mixture of black water and grey water is expected with addition of activated carbon. The observed, micropollutants removal from the UASB sludge increases possibilities for reuse, providing that adequate separation of activated carbon from sludge would be achieved.

References1. G. Zeeman, K. Kujawa-Roeleveld. Water Sci. Technol. 64, 1987-1992 (2011)2. M. S. de Graaff, N. M. Vieno, K. Kujawa-Roeleveld, G. Zeeman, H. Temmink, C. J. N. Buisman.

Water Res. 45, 375-383 (2011)3. L. Hernandez Leal, N. M. Vieno, H. Temmink, G. Zeeman, C. J. N. Buisman. Environ. Sci. Technol.

44, 6835-6842 (2010)

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O-A1-04-03

MATAL NANOPARTICLES FOR COLORIMETRIC AND FLUORESCENT BIO-SENSING APPLICATIONS IN

ENVIRONMENTAL MEDIUMS

Jalal Isaad1, Ahmida El Achari1

1ENSAIT, GEMTEX laboratory. F-59056 Roubaix. FrancePresenting author: [email protected]

There is interest in finding better and more efficient ways of detecting the bioanalytes that can be potentially harmful to the environment or human health. Among the anions and the heavy metals, cyanides, mercury and copper are the most dangerous which are lethal to humans at micromolar concentrations. Consequently, the presence of these anions in drinking water can give rise to a very serious risk to human health.

For this purpose, we developed in our laboratory efficient colorimetric and fluorescent water soluble molecular and polymeric chemosensors for the detection of cyanide [1-7], mercury [8,9] and cupper [10] ions about 10-7 M in biological systems with high selectivity over other ions. However, in the last decade the use of nanomaterials has been having a great impact in bio-sensing. In particular, the unique properties of metal / metal oxyde nanoparticles have allowed for the development of new biosensing platforms with enhanced capabilities in the specific detection of bioanalytes.

In this sense, we developed recently a large biosensing platform to detect the heavy metals in biological mediums by synthesizing fluorescent functionalized nanoparticles based on Nobel metals, silica [9] and silica coated magnetite [10] nanoparticles doped by an adequate fluorophore for the Hg (II) and Cu (II) colorimetric and fluorescent titrations.

In this conference, we will present our recent and the most significant results about the use of metal / metal oxide nanomaterials for the bioanalyte detection in environmental medium.

References1. J Isaad, A Perwuelz. Tetrahedron Letters. 51, 5810-5814 (2010).2. J Isaad, A El achari. Analytica chimica acta. 694, 120-127 (2011)3. J Isaad, A El Achari. Tetrahedron. 67, 4196-4201 (2011).4. J Isaad, A El achari. Tetrahedron. 67, 5678-5685 (2011).5. J Isaad, F salaun. Sensors and Actualitors B. 157, 26-33 (2011)6. J Isaad, A El Achari. Tetrahedron. 67, 4939-4947 (2011)7. J Isaad, A El Achari. Dyes and pigments. 97, 134-140 (2013)8. J Isaad, A El Achari. The Analyst.,138, 3809-3819 (2013)9. J Isaad, A El Achari. Tetrahedron., 69 (24), 4866 – 4874 (2013)10. J Isaad, A El Achari. Dyes and pigments. 99 (3), 878 – 886 (2013).

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O-A1-04-04

ENVIRONMENTAL ELECTROANALYSIS OF EMERGING POLLUTANTS

J. Barek

Charles University in Prague, Faculty of Science,University Research Centre UNCE ”Supramolecular chemistry”,

Department of Analytical Chemistry, UNESCO Laboratory of Environmental Electrochemistry, Albertov 6, CZ 12843 Prague 2, Czech Republic


The aim of this presentation is to show that even in the age of fascinating possibilities of modern spectrometric and separation methods, modern electroanalytical methods, especially in combination with non-traditional electrode materials and arrangements, can play useful role in environmental monitoring because of low running and investment cost, easy miniaturization, portability, and sufficient selectivity and sensitivity enabling detection of submicromolar to nanomolar concentrations of electrochemically active organic compounds. Attention will be paid to the use of mercury electrodes, which are up to now the best available sensors for detection of electrochemically reducible organic compounds (chemical carcinogens, endocrine disruptors, pesticides, etc.) enabling limits of detection of environmental pollutants down to nanomolar concentrations if coupled with adsorptive stripping voltammetry [1]. In many cases they can be successfully substituted by silver solid amalgam electrodes [2], which are more robust, non/toxic and compatible with measurements in flowing systems. The advantages of carbon paste electrodes [3] will be shown on detection of submicromolar concentrations of electrochemically oxidizable pollutants (chemical carcinogens, pesticides, nitro phenols and other priority pollutants). Extreme usefulness of boron doped diamond film electrodes [4] in environmental electroanalysis will be demonstrated on determination of submicromolar concentrations of environmental carcinogens, endocrine disruptors, and of biomarkers of their exposition in biological fluids. The presentation will be concluded with possible outlooks of modern electroanalytical methods in environmental analysis of emerging pollutants.

AcknowledgementFinancial support of this research by the Grant Agency of the Czech Republic (project PG206/12/G151) is gratefully acknowledged.

References1. J. Barek, K. Peckova, and V. Vyskocil, Curr. Anal. Chem. 4, 242 (2008).2. A. Danhel and J. Barek, Curr. Org. Chem. 15, 2957 (2011).3. H. Dejmkova, J. Zima, J. Barek, and J. Mika, Electroanalysis 24, 1766 (2012).4. K. Peckova and J. Barek, Curr. Org. Chem, 15, 3014 (2011).

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O-A1-04-05

SIMULTANEOUS DETECTION OF NEW PSYCHOACTIVE SUBSTANCES (NPSs) IN WASTEWATER OF GREECE

V. L. Borova1, N. S. Thomaidis1, C. Pistos2

1Department of Chemistry, National and Kapodistrian University of Athens, Panepistimiopolis 15771, Athens, Greece

2 School of Medicine, National and Kapodistrian University of Athens, Athens, GreecePresenting author: [email protected]

In recent years, new psychoactive molecules have appeared worldwide, often under “innocent” ap-pearances (house scents, bath salts, incenses, etc.), finding a wide and efficient distribution through the “e-commerce” or specialized shops. These products are claimed to contain only natural “non-illegal” compounds and consequently have no limitations in their commercial distribution, although exhib-iting important psychoactive effects similar to that obtained with illegal stimulants, such as meth-amphetamine, MDMA, cocaine or cannabis. This heterogeneous class of products are called “New Psychoactive Substances” (NPSs) and are undesirable, as very little is known about their effects and long term risks [1-3]. Among these substances, JWH-018, mephedrone, benzylpiperazine, and a-PVP have been detected in Greece [4]. The analysis of these compounds in wastewater samples provides valuable information about their consumption back in the community. The selected NPSs of this study comprise a broad range of substances, including synthetic cannabinoids (JWH-018, JWH-073, JWH-122, JWH-210, JWH-250, CP47,497), cathinones (mephedrone), piperazines (benzylpiperazine) and pyrrolidinophenones (a-Pyrrolidinopentiophenone, 4’-methylpyrrolidinobutyrophenone). A novel ultra performance liquid chromatography tandem mass spectrometry (UHPLC-MS/MS) method was devel-oped for their determination in wastewater samples. Comparison of various columns, mobile phases and SPE sorbents was performed. The final method employed solid phase extraction with PolyClean 2H sorbents for all the compounds, except BZP which was extracted using Strata XC and subsequent LC-MS/MS analysis in positive and negative electospray ionization, using a pentafluorophenyl (PFP) column. The new method was successfully applied in influents and effluents of six WWTPs of Santori-ni Island (a highly touristic resort in central Aegean Sea), and of the WWTP of Athens.

AcknowledgmentsThis research has been co-financed by the European Union and Greek national funds through the Oper-

ational Program “Education and Lifelong Learning” of the National Strategic Reference Framework (NSRF) – ARISTEIA 624 (TREMEPOL project).

References1. I. Vardakou, C. Pistos, and Ch. Spiliopoulou, Toxicol. Letters, 197 (3), 157-162 (2010).2. Ch. L. German, A. E. Fleckenstein, and G. R. Hanson, Life Sciences, 97 (1), 2-8 (2014).3. J. Van Amsterdam, D. Nutt, and W. Van den Brink, J Psychopharmacol, 27 (3), 317-324 (2013).4. Press announcement regarding EKTEPN meeting for “New dubstances, new challenges…“ (http://

www.ektepn.gr/index.php; Greek Monitoring Centre for Drugs (EKTEPN).

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O-A1-04-06

ADSORPTION OF SODIUM DIATRIZOATE (DTZ) BY ACTIVATED CARBON

J.B.Messaoud1, A.Houas1, M.Sanchez Polo2

1 UR Catalysis and Materials for Environment and Processes, University Campus Gabes,6072 Gabes, Tunisia

2 Departments of Inorganic Chemistry, Faculty of Science, University of Granada, 18071 Granada, Spain

[email protected]

The pharmaceutical compounds infect the aquatic and terrestrial environment. Antibiotics, which are specially designed to control bacteria in humans and animals, are an important group of pharmaceuticals and are generally used in all areas, they can influence the environment through different pathways such as manufacturing operations in the pharmaceutical industry, and their use in human and animals. The aim of this work is to adsorb the pharmaceutical compound Sodium Diatrizoate (DTZ) by an activated carbon was prepared by physical activation in steam at 800°C for 1h. Carbon was characterized by element analysis, moisture, ash, pHpzc, FTIR, surface area (SBET) and pore size. Equilibrium adsorption data followed both Langmuir and Freundlich isotherms. Two simplified kinetic models including pseudo-first-order and pseudo-second-order equation were selected to follow the adsorption processes [1].

Diatrizoate (DTZ)

Fig.1: Chemical structure of pharmaceutical compound

References[1] J. Rivera-Utrilla ; G. Prados-Joya, M. Sánchez-Polo, M.A. Ferro-García, I. Bautista-Toledo ; Journal of Hazardous Materials 170 (2009) 298–305

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O-A1-04-07

OCCURRENCE AND REMOVAL OF PHARMACEUTICALS, PESTICIDES AND FLUORO-SURFACTANTS FROM DRINKING WATER RESOURCES

S. Maeng1, Y. Lee2, C. Jaewon3

1Department of Civil and Environmental Engineering, Sejong University, 143-747, Seoul, Republic of Korea

2 School of Environment Science and Engineering, GIST-Gwangju Institute of Science and Technology, 500-712, Gwangju, Republic of Korea

3Water Quality Center, Kwater Institute, 305-730, Daejeon, Republic of KoreaPresenting author: [email protected]

Environmental contaminants of emerging concern, including pharmaceuticals and pesticides and endocrine disrupting compounds, represent a major concern in drinking water treatment and indirect wastewater portable reuse. The use of chemicals in each country depends on many factors such as type of industries, agricultural practices and living conditions, which also varies within a country depending on geographical location. Surface water is the major source of drinking water and has often been impacted by wastewater discharges or agriculture runoffs, raising the issue of possible occurrence of organic micropollutants in drinking waters. In this study, the occurrence and removal of seven pharmaceuticals (carbamazepine, ibuprofen, caffeine, iopromide, sulfamethazin, sulfathiazole, and, sulfamethoxazole), ten pesticides (carbendazim, isoprothiolane, hexaconazole, phosphamidon, simazine, kitazine, tebuconazole, metolachlor, butachlor, and atrazine), and two fluoro-surfactants (perfluorooctanesulfonic acid and perfluorooctane sulfonate) in ten drinking water treatment plants were investigated for more than a year of monitoring campaigns conducted every month. The removal efficiency of the selected micropollutants in conventional and advanced drinking water treatments were measured and compared. The occurrence of pesticides in the raw drinking waters was more influenced by season, and pesticides are often detected at a certain time of the year, usually in the spring. The occurrence pattern of the selected pesticides and pharmaceuticals in the source waters were different across the investigated drinking water treatment plants. The removal efficiencies of the investigated pharmaceuticals and pesticides varied significantly depending on their physicochemical properties such as log Kow. Most pesticides were efficiently removed by drinking water treatments, but metolachlor was poorly removed. Among the pharmaceuticals, carbamazepine was not effectively removed. Iopromide was the most frequently detected and showed the highest concentration in the investigated source waters. This suggests that iopromide can be served as an indicator for anthropogenic contamination (e.g., wastewater effluent discharge). This study reports the intensive monitoring results for the occurrence and removal efficiencies of various organic micropollutants indrinking waters, which is currently poorly understood. The selected organic micropollutants were determined at concentrations of a few ng/L to μg/L in the investigated source waters, which clearly supports the continuous future monitoring activities.

AcknowledgementsThis study was supported by the Korea Ministry of Environment as a part of “The Eco-Innovation project” (Global Top Project) GT-SWS-11-01-006-0.

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O-A1-05-02

TOXIC EFFECTS OF SILVER NANOPARTICLES ON PSEUDOKIRCHNE-RIELLA SUBCAPITATA (CHLOROPHYTA) ANALYZED IN A DROPLET

BASED MICROFLUIDIC SYSTEM

Jessika Teuber1*, Andrea Knauer1, J. Michael Köhler1

1Technische Universität Ilmenau, Institute of Chemistry and Biotechnology, Department of Physical Chemistry and Microreaction Technology,

*email: [email protected]

The Nanotechnology has become, in the meantime, an important economic factor with enormous reve-nues. Because of the different application fields of silver nanoparticles (AgNPs), AgNPs make a signif-icant contribution towards this development. This leads to an increasing release of AgNPs into the envi-ronment with unforeseeable consequences for aquatic ecosystems. Despite the environmental risk, the investigation of the toxicity of AgNPs is still in the initial phase. In contrast to commercial particularly small AgNPs which are stabilized with chemicals like functionalized alkanes [2], the stabilizer used in this work is citrate, in order to avoid toxic by-effects on the indicator organisms. The usage of droplet based microfluidic systems allows both, the synthesis of triangular silver nanoprisms and colloidal sil-ver nanoparticles with a narrow size distribution (Fig. 1), and comprehensive toxicity measurements. In the micro-droplet based systems, segments are generated by co-injection of an aqueous phase into the carrier solution PP9. The fluid segments were analyzed with an optical detector unit and stored either in Eppendorf cups (AgNPs synthesis) or in tube coils (toxicity examinations). After incubation, the seg-ments in the tube coils are analyzed again by pumping the PP9 inside and passing the segments through the optical detector unit again. The toxicity investigations of AgNPs to Pseudokirchneriella subcapita-ta (Chlorophyta) show a significant dependence on the size and the culture media (Fig. 2; Fig. 3).

Acknowledgment: Founding from the DBU (80012/740) is gratefully acknowledged.

[1] www.bmbf.de/pub/nanoDE-Report_2011.pdf

[2] F. Ribeiro et al.; Sci. Environment., 2014, 232–241

TOXIC EFFECTS OF SILVER NANOPARTICLES ON PSEUDOKIRCHNERIELLA SUBCAPITATA (CHLOROPHYTA) ANALYZED IN A DROPLET BASED MICROFLUIDIC SYSTEM

Jessika Teuber1*, Andrea Knauer1, J. Michael Köhler1 1Technische Universität Ilmenau, Institute of Chemistry and Biotechnology, Department of Physical Chemistry and Microreaction Technology, *email: [email protected]

The Nanotechnology has become, in the meantime, an important economic factor with enormous revenues. Because of the different application fields of silver nanoparticles (AgNPs), AgNPs make a significant contribution towards this development. This leads to an increasing release of AgNPs into the environment with unforeseeable consequences for aquatic ecosystems. Despite the environmental risk, the investigation of the toxicity of AgNPs is still in the initial phase. In contrast to commercial particularly small AgNPs which are stabilized with chemicals like functionalized alkanes [2], the stabilizer used in this work is citrate, in order to avoid toxic by-effects on the indicator organisms. The usage of droplet based microfluidic systems allows both, the synthesis of triangular silver nanoprisms and colloidal silver nanoparticles with a narrow size distribution (Fig. 1), and comprehensive toxicity measurements. In the micro-droplet based systems, segments are generated by co-injection of an aqueous phase into the carrier solution PP9. The fluid segments were analyzed with an optical detector unit and stored either in Eppendorf cups (AgNPs synthesis) or in tube coils (toxicity examinations). After incubation, the segments in the tube coils are analyzed again by pumping the PP9 inside and passing the segments through the optical detector unit again. The toxicity investigations of AgNPs to Pseudokirchneriella subcapitata (Chlorophyta) show a significant dependence on the size and the culture media (Fig. 2; Fig. 3). Acknowledgment: Founding from the DBU (80012/740) is gratefully acknowledged. [1] www.bmbf.de/pub/nanoDE-Report_2011.pdf [2] F. Ribeiro et al.; Sci. Environment., 2014, 232–241

Fig. 3 Figure 1: DCS spectra of the used citrate stabilized AgNPs Figure 2: Toxicity of 10.3nm-AgNPs to Pseudokirchneriella subcapitata in EPA and OECD medium Figure 3: Toxicity of 3.7nm- and 4.7nm-AgNPs to Pseudokirchneriella subcapitata in ISO medium

Fig. 1 Fig. 2

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O-A1-05-03

INDIVIDUAL AND MIXTURE TOXICITY OF PHARMACEUTICALS AND PHENOLS ON FRESHWATER ALGAE Chlorella vulgaris

Elisabeth Geiger1, Melek Türker Saçan2, Romana Hornek-Gausterer3

1FH-Technikum Wien (University of Applied Sciences), Höchstädtplatz, 1200 Vienna, Austria2Bogaziçi University, Institute of Environmental Sciences, Hisar Campus, Bebek 34342, Istanbul,

Turkey3Environment Agency Austria, Spittelauer Lände 5, 1090 Vienna, Austria


Aquatic ecosystems have been severely threatened by discharges of toxic compounds. Increasing chemical usage for domestic, agricultural and industrial purposes, such as phenols and pharmaceuticals, need to be evaluated for potential threat, as they can be detected in water bodies throughout the world. Pharmaceuticals are designed to have a biological therapeutic effect, but may also cause similar effects in non-target organisms. Thus, pharmaceutical pollutants have become an emerging area of concern. The chemicals legislation, spearheaded by REACH and CLP, aims to ensure a high level of protection of human health and the environment, but it is rarely based on the assessment of combination effects of chemicals. The current used regulatory approaches are based on the evaluation and risk assessment of individual chemicals. Since human beings and their environment are exposed to a wide variety of substances, there is an increasing concern about the potential adverse combination effects of chemicals. In this study, the toxicity experiments have been carried out based on the algal growth inhibition test OECD No. 201 (OECD 2006) criteria prepared by the Organization for Economic Cooperation and Development. Individual and binary mixture toxicity experiments of selected pharmaceuticals (ibuprofen and ciprofloxacin) and phenolic compounds (2.4-dichlorophenol and 3-chlorophenol) have been performed with freshwater algae Chlorella vulgaris. Nominal concentration of test solution of each chemical was measured at the end of the experiment by instrumental analytic devices. Inhibition of growth was used as the test endpoint, expressed as the logarithmic increase in biomass (average specific growth rate) during an exposure period of 96 hours determined by daily measurements of optical density at 680 nm. All substances tested had a significant effect on Chlorella vulgaris population density and revealed IC50 values < 100 mg/L. After determination of the single toxicity for each substance, binary mixture tests were conducted using proportions of the respective EC50s (=1 toxic unit (TU)). When a 50% effect occurs at less than 1 TU, the mixture was considered to be greater than additive, or synergistic. The mixture dose-response curve was compared to predicted effects based on both the concentration addition and the independent action model as suggested in regulatory risk assessment. It could be demonstrated that the combined toxicity of pharmaceuticals and phenols can lead to synergistic effects. The potential impacts of pharmaceuticals on aquatic organisms could lead to the inclusion among new priority candidates in the current or future revision of the EU List of Priority Substances relevant to the Water Framework Directive 2000/60/EC [1].

References

1. P. Bottoni, S. Caroli, A. Barra Caracciolo. Pharmaceutical as priority water contaminants. Environ. Toxicol. Chem. 92, 549-565 (2010).

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O-A1-05-04

SIMULTANEOUS DETERMINATION OF PHARMACEUTICALS IN ENVIRONMENTAL SOLID SAMPLES BY ULTRASONIC-ASSISTED EXTRACTION (UAE) – AN EXPERIMENTAL DESIGN APPROACH

S. Ferhi1, M. Bourdat-Deschamps1, J.J. Daudin2, S. Nélieu3, 1 INRA-AgroParisTech, UMR 1091 EGC, 78850, Thiverval-Grignon, France

2 AgroParisTech-INRA, UMR 518 MIA, 75231, Paris, France 3 INRA, UR 251 PESSAC, 78026, Versailles, France


Administration of pharmaceuticals is the most common practice for human and animal disease control and treatments. Large fractions of administrated pharmaceuticals are not assimilated or metabolised but excreted and therefore transferred to wastewater and manure, respectively. Sewage sludge and manure are recycled in agriculture for their fertilising values and thus contribute to the dissemination of pharmaceuticals into the environment (soil, surface and ground water). Little is known about the potential toxic effects of these pharmaceutical residues in the environment. It is therefore necessary to develop analytical methods for their quantification. It is a real challenge due to the complexity of the solid matrices and the low level contents of many pharmaceuticals.

We optimised the analysis of sixteen pharmaceuticals including eight antibiotics in soil and sewage sludge. The samples were extracted by Ultrasonic-Assisted Extraction (UAE), purified according to an adapted QuEChERS method and analysed by online solid-phase extraction coupled to ultra-high performance liquid chromatography with tandem mass spectrometry (online SPE-UHPLC-MS-MS) [1]. Two successive experimental design approaches were performed, in order to evaluate a large number of parameters and to optimise experimental conditions.

Literature data described various experimental conditions for pharmaceutical extraction from solid matrices. According to the compound properties, four parameters appeared to be crucial for UAE efficiency: the nature of the organic solvent and its proportion, the nature of the aqueous phase (buffers, modifying agents) and its pH. For each matrix, a screening experimental design was performed to identify the factors and/or their interactions that had a statistical influence on the recovery. A response surface design was then performed to find the best extraction conditions. In sewage sludge, even if the pharmaceuticals presented various behaviours that could be explained by their physicochemical properties, a compromise between the optimal conditions was possible. We thus proposed a single condition allowing efficient extraction. In the case of soil, a selection of two successive extraction conditions was done due to opposite behaviour of compounds: fluoroquinolones and sulfonamides presented contrasted optima in terms of pH and chelating agent abundance. In the presentation, the approach will be described, focussing on two compounds of these families.

References[1] M. Bourdat-Deschamps, S. Leang, N. Bernet, J.J. Daudin, S. Nélieu, J. Chromatogr. A (2014) in

press, DOI 10.1016/j.chroma.2014.05.006

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O-A1-05-05

THE IMPORTANCE OF QUALITY CRITERIA DURING INVESTIGA-TION OF MICROPOLLUTANTS IN THE COMPLEX MATRIX URINE BY

A LC-MS/MS MULTIMETHOD

Linda Schlittenbauer, Bettina Seiwert, Thorsten Reemtsma

Helmholtz-Centre for Environmental Research, Dept. Analytical Chemistry, Permoserstrasse 15, 04318 Leipzig, Germany


An increasing number of so-called multiresidue-methods employing LC-MS/MS have been developed for water samples during the last years. Analogously we have developed a multimethod for human urine to study the human exposure to organic micropollutants. Quantification of 90 micropollutants is possible by UPLC – QqQ-MS (Xevo TQ-S).

Analyte selection considers the relevance of the contaminant to the water cycle and was extended by metabolites (environmental as well as human). Limits of detection (LOD) were in water samples in the lower ng/L range from pure water for most analytes. In urine, however, LODs were 1 to 2 orders of magnitude higher due to matrix effects. Another critical aspect in this complex matrix is the avoidance of false positive results. For this purpose three often proposed criteria [1] had to been met:

i) detection of two MRM transitions (quantifier and qualifier), ii) correctness of the retention time (≤ 0.02 min compared to standard), iii) ion ratio of Q and q (within 80 - 120% compared to standard).

One critical example is the determination of the corrosion inhibitor benzotriazole in urine [2]. In our analyses there was a significant disturbance at that retention time which seemed to indicate the widespread human exposure to benzotriazole. However the wrong ion ratio (Q/q) proved this to be a false positive finding.

During the development of multimethods less attention is usually directed to chromatographic separation. For benzotriazole it is shown that an optimized LC separation is favorable despite the longer measuring time. No cleanup was found that helped to remove the disturbing urine constituents.

References

1. F. Hernandez, J.V. Sancho, O.J. Pozo, Anal Bioanal Chem 382, 934 (2005).

2. A.G. Asimakopoulos, A.A. Bletsou, Q. Wu, N.S. Thomaidis, K. Kannan, Anal Chem 85, 441 (2013).

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O-A1-05-06

CONCENTRATIONS AND TRENDS OF NOVEL BROMINATED HYDROCARBONS IN THE WATER COLUMN AND SEDIMENTS

OF LAKE GENEVA (SWITZERLAND): DETECTION AND QUANTIFICATION USING GC×GC-µECD AND GC×GC-ENCI-TOFMS

Saer Samanipour1, J. Samuel Arey 1,2

1Environmental Chemistry Modeling LaboratorySwiss Federal Institute of Technology in Lausanne (EPFL),

1015, Lausanne, Switzerland2 Department of Environmnetal Chemistry

Swiss Federal Institute of Aquatic Science and Technology (EAWAG), Dubendurf, Switzerland


The so-called novel brominated frame-retardants (NBFRs) have been introduced due to the ban on the polybrominated diphenyl ethers (PBDEs). While PBDEs have been studied extensively in different environmental compartments, the NBFRs and the degradation products of legacy BFRs have been less investigated in the environment. Using GC×GC-µECD and GC×GC-ENCI-TOFMS, we analyzed the water column of Lake Geneva (Switzerland) near the outfall of the municipal wastewater treatment plant (WWTP) of Lausanne for several brominated hydrocarbons. We also analyzed sediment samples from four different locations in the lake for these brominated hydrocarbons. We detected and quantified 2,3,4,5,6-pentabromoethylbenzene (PBEB), 4-bromobiphenyl (4BBP), and 1,3,5-tribromobenzene (TBB) in both the middle and deep water column of Lake Geneva, and we also detected 4BBP and PBEB in several sediment samples. Whereas PBEB is an NBFR, both TBB and 4BBP have other industrial uses not as flame retardants. However TBB is also a potential degradation product of the NBFR hexabromobenzene, and 4BBP is a potential degradation product of higher brominated biphenyls (legacy BFRs).

All three of these brominated hydrocarbons were found in elevated concentrations in the middle water column (70 m) compared to the deep water column (170 m) of Lake Geneva. Additionally, for all three compounds, higher concentrations were observed in the sediment samples obtained from the middle deep lake and from a coastal bay containing a major WWTP outfall. Lower sediment concentrations were observed in the western lake basin near the Rhône River inflow. The observed spatial and temporal trends provide insight into potential inputs (i.e., urbanized areas, atmosphere, tributaries, and WWTP) for these brominated hydrocarbons. As a basis for comparison, we also report concentrations of five legacy BFRs (four PBDEs and hexabromobiphenyl) in these same samples.

We estimated eleven environmentally relevant partitioning properties of the three brominated hydrocarbons based on their GC×GC retention times, using a recently developed estimation method. These estimated properties were used to make inferences about the environmental fate and behavior of these brominated hydrocarbons. We also report high resolution accurate m/z values of the fragments of our target analytes with a mass accuracy of ± 5 mmu produced using GC×GC-ENCI-TOFMS. This is the first study to report the environmental occurrence of 4BBP and to provide environmental partitioning property estimations, their accurate m/z values, and the ENCI-TOFMS fragmentation patterns for 4BBP, TBB, and PBEB.

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O-A2-01-02

FATE OF NATURAL ORGANIC MATTER AT A FULL-SCALE DRINKING WATER TREATMENT PLANT

A.Papageorgiou1, N. Papadakis2, D. Voutsa1

1Environmental Pollution Control Laboratory, Department of Chemistry, Aristotle University of Thes-saloniki, GR-54124, Thessaloniki, Greece

2Laboratory of Hygiene, Faculty of Medicine, Aristotle University of Thessaloniki, GR-54124, Thes-saloniki, Greece


Natural Organic Matter (NOM) is a complex mixture of organic compounds present in surface waters. NOM in aqueous environments originate from plants and soil (allochtonous sources) and from bio-logical activities within the water body (autochtonous sources) [1]. The amount and characteristics of NOM depends on climate, geology and topography. The presence of NOM in drinking water concerns aesthetic problems, such as odor, taste and colour. Upon drinking water treatment, NOM is of major concern, since it is precursor parameter of ozonation and chlorination disinfection by-products (DBPs) [2,3]. Finally, biodegradable organic carbon in finished water can enhance the bacterial regrowth in distribution system [4].

The aim of this study was to investigate the occurrence of NOM as dissolved organic carbon (DOC) and its characteristics (UV absorbance, SUVA, fluorescence intensity, hydrophobic and hydrophilic fractions and biodegradable fraction) in the Drinking Water Treatment Plant of Thessaloniki, Greece. This plant receives surface water from Aliakmonas river and employs various treatment steps (pH cor-rection, pre-ozonation, flocculation/coagulation, sand filtration, ozonation, filtration through activated carbon and chlorination) in order to provide 150000 m3/d of drinking water. Water samples have been collected after each treatment step every month for a period of one year.

Temporal variation of DOC concentration and characteristics of raw water are presented. The contri-bution of each treatment process in removal of DOC and changes in its characteristics are discussed as well as potential relationships with ozonation-DBPs (carbonyl compounds) and chlorination-DBPs (THMs, HAAs).

Acknowledgement: This study was conducted under the cooperation and financially support of Thessa-loniki Water Supply and Sewerage Co S.A. (EYATH).

References1. A. Matilainen, Chemosphere 83, 1431-1442 (2011).2. A.Papageorgiou, D. Voutsa and N. Papadakis, Sci. Total Environ. 481, 392-400 (2014).3. R. Gough, Sci. Total Environ. 468-469, 228-239 (2014).4. M.K. Ramseier, A. Peter, J. Traber and U. von Gunten, Water Res. 45, 2002-2010 (2011).

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O-A2-01-03

DETERMINATION OF PBDEs BY VALIDATED GC-IDMS METHOD IN WATER WITH LOW DETECTION LIMIT

B. Binici1, M. Bilsel1, A. C. Gören1, C. Swart2, R. Philipp3

1TÜBİTAK National Metrology Institute, 54 41470 Gebze/Kocaeli, Turkey2Physikalisch-Technische Bundesanstalt, Bundesallee 100, 38116 Braunschweig, Germany

3BAM Federal Institute for Materials Research and Testing, Richard-Willstaetter-Str., 11, 12489 Berlin, Germany


Water is the mainstay of the environment and its degradation has serious consequences. The European Union performed European Water Frame Directive (WFD) to improve water quality, in the year 2000. The purpose of this directive is to establish a protective framework for all inland surface waters in order to prevent deterioration and promote their sustainable use through protection in the medium and long term. The WFD is a highly complex legal and technical document and the quantification limits required are extremely low [1]. Regarding this purpose, in this study, method development includes development and validation of extraction, preconcentration and isotope dilution mass spectrometry (IDMS) detection technique. Liquid/liquid extraction is used as an extraction technique and preconcentration is necessary to achieve the required LOQ. A GC-IDMS method was developed and validated to determine BDE-28, BDE-47, BDE-99, BDE-100, BDE-153 and BDE-154 in water with 0.15 ngL-1 LOQ value for ƩPBDEs. In method validation, identification, LOD and LOQ and trueness were evaluated and uncertainty of the method was determined according to GUM. The recovery, LOD and LOQ and relative uncertainty values of the method are presented in Table 1.

Table 1. Recovery, LOD and LOQ and relative uncertainty values of the methodCompound Recovery (%) LOD LOQ Relative uncertainty (%)BDE-28 81,75 0,0069 0,0232 5,53BDE-47 94,6 0,0063 0,0211 5,26BDE-99 93,3 0,0132 0,0441 6,98BDE-100 96,24 0,0133 0,0442 8,69BDE-153 92,49 0,0241 0,0805 14,79BDE-154 93,87 0,0467 0,1558 27,49

This work is part of EMRP-project “ENV08 WFD-Traceable measurements for monitoring critical pollutants under the European Water Framework Directive (WFD-2000/60/EC)”. The EMRP is jointly funded by the EMRP participating countries within EURAMET and the European Union.

References1. European Commission, Directive 2000/60/EC of the European Parliament and of the Council of 23

October 2000 establishing a framework for Community action in the field of water policy, OJ Eur. Comm. L 327

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O-A2-01-04

APPLICATION OF AUTOMATED SURFACE WATER QUALITY MONITORING SYSTEM ON RIVER BASIN AND CONNECTED FOR

EXPERT SYSTEM

Zs. Kovács1, Z. Zsilák2, I. Cretescu3, L. Simon4, T. Yuzhakova1, Á. Rédey1

1University of Pannonia, Institute of Environmental Engineering, H-8200, Veszprém, Hungary2University of Pannonia, Department of General and Inorganic Chemistry, H-8200, Veszprém,

Hungary3”Gheorghe Asachi” Technical University of Iasi, Faculty of Chemical Engineering and

Environmental Protection, Department of Environmental Engineering and Management, 700050, Iasi Romania

4Combit IT Share of Company, H-, Budapest, HungaryPresenting author: [email protected]

According to the Directive 2000/60/EC our waters have to reach the water quality category of good quality. In order to elaborate the required programs information are needed. The main priority is to build up the network of monitoring system of water catchment area. Remote-controlled automatic on-line monitoring systems provide more useful and continuous monitoring capabilities by providing accurate data on change in water quality in real time. In our functional terms, the network includes three principal subsystems: the monitoring station, communication system and remote station. Main aspect of integrated river basin monitoring (Fig.1):- background information of catchment area, - identification of pollution sources and environmental experts able to select indicator parameters, - optimization of sustainable and maintenance cost.

Figure 1: Network monitoring in River Basin

The aim of the project is that the load on the Veszprém Séd stream can be determined on the basis of comprehensive physical-chemical measurements. The mobile station is able to analyze continuously, such as a temperature, pH value, conductivity, turbidity, nitrate-N, nitrite-N, ammonium-N and orthophosphate-P concentrations. Data transfer was provided via GPRS to database server and following the data processing and modelling the results were put on WEB surfer.

Acknowledgement: This work was supported by the European Union and co-financed by the European Social Fund in the frame of the TÁMOP-4.1.1.C-12/1/KONV-2012-0015. This work was supported by the European Union and co-financed by the European Social Fund in the frame of the TÁMOP-4.2.2.A-11/1/KONV-2012-0064.

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O-A2-01-05

ON THE ADSORPTION OF HYDROCARBONS ON MICRO AND MESOPOROUS HIGH SILICA MATERIALS: A COMBINED

EXPERIMENTAL AND COMPUTATIONAL STUDY

C. Bisio1, V. Sacchetto1, M. Cossi1, G. Gatti1, G. Paul1, I. Braschi1,2, G. Berlier3, L. Marchese1

1Department of Scienze e Innovazione Tecnologica and Centro Nano-SiSTeMI, University of Piemonte Orientale, Alessandria, Italy

2Department of Scienze Agrarie, University of Bologna, Bologna, Italy3Department of Chimica and NIS Centre of Excellence, University of Torino, Italy


Fuel-based compounds are pollutants generally coming from industrial waste and usually present in water and soil from areas where oil refineries and gas stations are situated. Among all contaminants, methyl tertiary butyl ether (MtBE), toluene and n-hexane were selected as model molecules representative of the most common classes of pollutants. The use of sorbent materials as micro and mesoporous silicas to adsorb these contaminants from polluted areas is receiving increasing attention [1]. The sorption capacity of silicas, with different nature and number of surface OH sites and pore size architecture, were studied. High silica ZSM-5 (SiO2/Al2O3= 280), mordenite (MOR) and Y zeolites (both with a SiO2/Al2O3 ratio of 200) [2] were indeed chosen for their peculiar physico-chemical properties. Results obtained on microporous solids were compared with those of ordered mesoporous MCM-41 silicas. The interactions of the three pollutants on the zeolites and MCM-41 silicas were studied by means of both experimental and computational approaches (Fig.1). FTIR and SS-NMR spectroscopy were used to elucidate the host/guest interactions between surface of sorbents and model molecules. H-bonding and van der Waals interactions occurring between the surface of solids and molecules were modeled by DFT calculations. Gravimetric analysis allowed to quantify the different sorption capacities of the materials. The adsorption of contaminants - as single pollutants or in binary mixtures - on the three zeolites was not reduced when it was conducted in the presence of water sorbed onto zeolites, thus suggesting reasonable performances under wet working conditions. On the contrary, water affects the structure and surface adsorption sites of MCM-41 by lowering the retention capacity of the three fuel-based pollutants. The sorbent was hence modified by grafting with hexamethyldisilazane to enhance the hydrophobicity of the silica surface.

References1. R.S. Bowman, Micropor. Mesopor. Mater., 61, 43 (2003). 2. V. Sacchetto, G. Gatti, G. Paul, I. Braschi, G. Berlier, M. Cossi, L. Marchese, R. Bagatin, C. Bisio, Phys.Chem. Chem. Phys., 15, 13275 (2013).

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O-A2-01-06

QUALITY OF MONITORING MEASUREMENTS UNDER THE WATER FRAMEWORK DIRECTIVE: TECHNICAL CHALLENGES CREATED BY

THE REGULATORY REQUIREMENTS

M. Ricci, B. Koleva, R. Lava, I. Dosis, S. Elordui-Zapatarietxe, H. Emteborg, A. Held, H. Emons.

European Commission, Joint Research Centre, Institute for Reference Materials and Measurements (IRMM), 2440, Geel, Belgium


Forty-five priority substances (PSs) are regulated by the recently approved Directive 2013/39/EU [1], which introduced twelve new organic pollutants supplementing the first list of thirty-three given in the Directive 2008/108/EC [2]. This Directive also establishes Environmental Quality Standards (EQS) in biota for some of the PSs.Directive 2009/90/EC [3] lays down stringent technical specifications for chemical analysis and monitoring of water status. The laboratories appointed by the Member States as responsible for the chemical water monitoring should apply quality management system practices accepted at international level and demonstrate their competence by participation in proficiency testing (PT) programs and analysis of available reference materials (RMs).For many of the PSs there is a significant lack of appropriate quality assurance/quality control (QA/QC) tools to support and validate the monitoring measurements according to the performance criteria imposed by the legislation [3], in terms of validated methods of analysis, PT schemes and certified reference materials (CRMs).An overview of the present status with respect to the availability of these QA/QC tools for the Water Framework Directive (WFD) relevant matrices (water, biota and sediment) will be presented, highlighting the gaps and indicating some on-going developments. In specific, the choice of the proper CRM can be critical for the laboratory responsible of reporting monitoring data in the context of the WFD. The CRMs should be fit-for-purpose e.g. with certified values close to the EQS (and sufficiently small uncertainty), mimicking the real environmental sample matrices and accompanied by appropriate information for optimal use [4]. All of the latter can considerably improve the quality of the measurement results. Examples of (C)RMs for the analysis of some PSs in fish and water under production at JRC-IRMM will be illustrated.

References1. European Commission, Directive 2013/39/EU of the European Parliament and of the Council of 13

August 2013, Off. J. Eur. Union L 226, 119 (2013).2. European Commission, Directive 2008/105/EC on environmental quality standards in the field of

water policy Off. J. Eur. Union L 201 (2009) 36.3. European Commission, Directive 2009/90/EC of the European Parliament and of the Council of 31

July 2009, Off. J. Eur. Union L 201, 36 (2009).4. M. Ricci, I. Kourtchev and H. Emons, Trends Anal. Chem. 36, 47 (2012).

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O-A2-02-02

ADSORPTION OF SULFONAMIDE ANTIBIOTICS ONTO HIGH SILICA ZEOLITES: FROM MULTIDISCIPLINARY MODEL STUDIES TO

APPLICATIONS TO REAL WATERS

I. Braschi1,3, S. Blasioli1, E. Buscaroli1, A. Martucci2, M. Cossi3, L. Marchese3

1Dipartimento di Scienze Agrarie, Università di Bologna, Bologna, Italy2Dipartimento di Fisica e Scienze della Terra, Università di Ferrara, Ferrara, Italy

3Dipartimento di Scienze e Innovazione Tecnologica and Centro Nano-SiSTeMI, Università del Piemonte Orientale, Alessandria, Italy


Owing to their environmental diffusion and persistence, sulfonamide antibiotics (sulfa drugs) are responsible to induce high level of resistance in bacteria. The sulfonamide anionic nature makes them highly mobile along soil profile and is responsible for their accumulation into water bodies. In order to limit the diffusion of resistance determinants, it is of utmost importance to identify adsorbents for this antibiotic family to be adopted for water cleanup purpose. Three high silica zeolites (Y, MOR, ZSM-5) have been tested for their capability to extract sulfonamides from water. Kinetics, capacity and reversibility of the adsorption have been studied along with sulfonamide arrangement into the porosities of each zeolite [1-3].The sulfa drugs irreversibly adsorbed onto zeolite Y at ca. 26% on average and with the process equilibrium reached in less than 1 min [1,3]. The favorable adsorption kinetics was confirmed when zeolite Y was applied to both fresh and sea waters although the dissolved organic matter occurring in natural water compartments can be retained as well but with a kinetics less favorable than that shown by sulfa drugs. The main host-guest & guest-guest interactions between zeolites and sulfa drugs were defined by IR and SS-NMR analysis, and augmented by computational studies. H-bonds and van der Waals type interactions between single molecules and zeolite Y or ZSM-5 were responsible for the irreversible extraction of sulfa drugs from water [1,3]. The occurrence of intramolecular medium strength H-bond in small sized sulfa drugs upon adsorption inside zeolite Y cage revealed the formation of dimeric species whose amidic or imidic tautomeric form were identified [1,3]. Rietveld refinement and IR analysis revealed that sulfa drugs incorporation into MOR caused a close vicinity of the heterocycle ring to the side pocket oxygens [2,3]. At 65°C, MOR gave rise to a sulfachloropyridazine reaction product with a 100% selectivity and SNAr mechanism [2]. Among the regeneration strategies approached, the thermal treatment and solvent extraction gave the best results.

References[1] I. Braschi, G. Paul, G. Gatti, M. Cossi, L. Marchese. RSC Advances, 3, 7427 (2013).[2] A. Martucci, M.A. Cremonini, S. Blasioli, L. Gigli, G. Gatti, L. Marchese, I. Braschi. Micropor. Mesopor. Mat. 170, 274 (2013).[3] S. Blasioli, A. Martucci, G. Paul, L. Gigli, M. Cossi, C.T Johnston, L. Marchese. J. Coll. Interface. Sci., 419, 148 (2014).

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O-A2-02-03

POLYCATIONIC RESINS FOR ANIONIC DRUGS CAPTURE AND RELEASE. CASE OF NALIDIXIC ACID AND PENICILLIN V

F. Lemée, I. Clarot, B.S. Nguyen, P. Lemiere, M. Mourer, J.-B. Regnouf-de-Vains

MOBAT team, SRSMC, UMR 7565, CNRS-Université de Lorraine Boulevard des Aiguillettes, 54506 VANDOEUVRE-LES-NANCY, France


Polymers may play an important role in the capture and release processes for depolluting waste waters, notably in urban areas with very strong density of population. Poisoning of waste waters by drugs or metabolites imply heavy treatments before obtaining tap water. Among drugs, antibacterial agents are problematic as they are widely used and susceptible to interfere with microorganisms used in water treatment plants.

In this sense, we have studied some commercial and homemade cationic polymers, one of them being the well-known cholestyramine (QUESTRAN®). Two antibacterial models which are a quinolone (na-lidixic acid, sodium and potassium salt) and a β-lactam (penicillin V, potassium salt) have been chosen for this study. We present here the results obtained by means of reversed phase CLHP1. Very interesting results were obtained with one of our homemade polymers in terms of capture-release capacities and recyclability.

Cationic polymer

(KCl)aq

or

(NaCl)aq

NN

O

O

O

N

N

O

O

O

N

N

OO

O

P

CAPTURERELEASE

NN

O

O

O

In Water

M+

NN

O

O

O

M+

M+

P

Figure 1: Example of capture and release of Nalidixic acid using a cationic polymer Anions have been omitted for clarity

References1. H. Massimba Dibama, I. Clarot, S. Fontanay, A. Ben Salem, M. Mourer, C. Finance, R. E. Duval,

J.-B. Regnouf-de-Vains, Bioorg. Med. Chem. Lett. 19, 2679-2682 (2004).

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O-A2-02-04

LIGAND SIZE POLYDISPERSITY EFFECT ON SSCP SIGNAL INTERPRETATION

Luciana S. Rocha 1, Wander G. Botero 2, Nuno Guerreiro Alves 3, José Moreira 3, Ana Rosa Costa3 & José Paulo Pinheiro1

1 IBB/CBME, DQF/FCT, University of Algarve, 8005-139 Faro, Portugal.2 Federal University of Alagoas, 57160000, Arapiraca-Alagoas, Brazil 3 CIQA, DQF/FCT,Universidade do Algarve, 8005-139 Faro, Portugal


In natural waters only a small portion of the total dissolved metal exists as free hydrated cations, because metal ions form stable complexes with a large variety of dissolved inorganic and organic ligands and also adsorbs onto colloids and suspended matter. Most of these ligands have a polyfunctional and polyelectrolytic character and, thus, have a broad range of free energies of complex formation, formation/dissociation rate constants and sizes [1]. Therefore, to establish the relationship between metal ion speciation, bioavailability and biouptake and consequently, the foundations for dynamic risk assessment, it is fundamental to understand the interaction of trace metals with heterogeneous samples and their kinetic characteristics. The knowledge of dynamics factors remains a challenging problem since very few techniques combine the potential to perform dynamic speciation analysis and high sensitivity. Scanning stripping chronopotentiometry (SSCP) fulfils these requirements and the capacity of this technique to obtain dynamic information and to evaluate the chemical heterogeneity has already been investigated and it is well understood [2]. Nevertheless, very little information is known regarding the effect of ligand size polydispersity on metal binding studies using stripping electroanalytical techniques. The main goal of the present work is to investigate the effect of size polydispersity of metal ions binding to mixtures of polymers by SSCP signal. The binding of Cd(II) and Pb(II) to individual charged carboxyl terminated polystyrene sulfonate ((PSS)n-COOH) polymers of different sizes (4, 10 and 30 KDa) was investigated, followed by the metal binding to binary and ternary mixtures of these polymers. The experiments performed showed, as expected, that the stability constants K’ obtained from the shift of the half-wave potential of the SSCP curves were additive according with DeFord and Hume [3] formalism. It was demonstrated for the first time that the metal-ligand diffusion coefficient DML, calculated from the decrease of transition time of the SSCP waves, were also additive for multiple complexes (MLi) simultaneously present in solution, i.e., the sum of the individual contributions from each bound metal with a differently sized polymer. The results demonstrate that the average diffusion coefficient (Davg) concept can be used in mixtures of complexing ligands of different sizes. It can also be stated that the information contained in the binding studies of different metals with the same polymer mixture might be useful to elucidate the nature of the said mixture.

References1. J. Buffle, Complexation reactions in aqueous systems. An analytical approach. Ellis Horwood Pub., Chichester (1988).2. J. P. Pinheiro, H. P. van Leeuwen, J. Electroanal. Chem. 570, 69 (2004).3. D.D. DeFord, D. N. Hume, J. Am. Chem. Soc., 73 (11), 5321 (1951).

The authors thank Fundação para a Ciência e a Tecnologia (FCTANR/AAG-MAA/0065/2012) and Faculdade de Ciências e Tecnologia (Pest-OE/EQB/LA0023/2013 and PEst-OE/QUI/UI4023/2014) for funding support. L.S. Rocha,and N. G. Alves also thank their grants (FCT project FCTANR/AAG-MAA/0065/2012) and the University of Algarve/CBME and University of Algarve/CIQA, respectively. Wander G. Botero thanks Capes (9813/13-6).

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O-A2-02-05

CHEMICAL STRATEGIES FOR SURFACE MODIFICATION OF MAGNETIC NANOSORBENTS

Ana L. Daniel-da-Silva1, Tito Trindade1

1Department of Chemistry-CICECO, Aveiro Institute of Nanotechnology, University of Aveiro, 3810-193 Aveiro, Portugal


Water pollution is a global problem that has raised the attention of the scientific community for the need of more effective solutions in this field. Nanotechnology related approaches have appeared in recent years with very promising possibilities, that include the development of new materials for water treatment and innovative methods of contaminants detection and monitoring. Among these topics, the development of efficient nanosorbents has been particularly investigated due to their high impact, namelly in water treatment technologies.[1] In this context, our research group has been interested in the development of magnetic nanomaterials as new sorbents for the magnetic uptake of water pollutants. This communication gives a brief overview of chemical strategies that have been employed by our group to achieve efficient magnetic nanosorbents for pollutants of diverse origin.

Iron oxides have been mainly used in this context because they exhibit high magnetic susceptibility to facilitate fast separation in a moderate magnetic field and, are relatively inexpensive and do not pose major toxicity concerns. However the strategies reviewed here can be extended to other magnetic nanostructures and illustrative examples will be presented. Two selected types of nanosorbents will be discussed in more detail in which the chemistry of the surfaces has a determinant role in the removal process. Interestingly these materials have been designed by merging simple concepts typically found in inorganic chemistry and colloidal science. Thus a first example will focus on colloidal core/shell nanoparticles comprising a magnetic core (Fe3O4) coated with siliceous shells, that were functionalized with S donor ligands to achieve efficient capture of soft acids, such as Hg(II). As an alternative and distinct surface modification strategy, magnetic iron oxides have been coated with polysaccharides and their use in the magnetic removal of organic water pollutants has been investigated. The role of the biopolymer on the sorption capacity will be discussed together with chemical modifications introduced in the nanomaterials in order to improve the versatility of the purification process.

References

[1] M. Khajeh, S. Laurent, K. Dastafkan, Chem. Rev. 113, 7728 (2013).

Acknowledgments

This research was financed by the national funding from FCT (Fundação para a Ciência e a Tecnologia) through the project PTDC/CTM-NAN/120668/2010, by FEDER funding through program COMPETE and by national funding through FCT in the frame of project CICECO - FCOMP-01-0124-FEDER-037271 (FCT Pest-C/CTM/LA0011/2013).

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O-A2-02-06

CHEMODIVERSITY OF ORGANIC XENOBIOTICS IN THE ENVIRONMENT:

A NAMING AND SCIENTIFIC NIGHTMARE?

P. Garrigues

Institute of Molecular Sciences (ISM) University of Bordeaux / CNRS, Talence, [email protected]

Since the first discovery of organochlorine pesticides in the 60’s, each following decade has

shown new discoveries of organic environmental contaminants. Hydrocarbons (HCs, PAHs) in the 70s related to oil pollution, chlorinated compounds ( PCBs revisited, PCDD, PCDF) in the 80s related to waste incineration and combustion sources, 2nd and 3rd generation pesticides (N-, S-, P-containing compounds) in the 90s linked to agriculture practices and finally nowadays the cloudy PPCPs used by everybody on the planet.

In parallel, the toxicity knowledge of organic compounds has strongly increased. In environmental monitoring studies, molecular markers of toxicity are now strongly associated

with the detection level of contaminants.

As a consequence, a confusing puzzle of acronyms is associated with either chemical family

names (PFOs, PBBs), physico-chemical properties (PBT), toxicity end-points (ED), or intended usage (PPCPs). These acronyms are used by many environmental stake holders industry, research, regulatory agencies, NGOs) expanding the confusion.

This presentation will focus on organic contaminants on research, toxicity and regulation aspects. It will attempt to clarify all these concepts and to show how some of them have been developed.

HC : Hydrocarbon ; PAH : Polycyclic aromatic hydrocarbon ; PCB, PCDD, PCDF : polychlorobiphenyl, - dibenzodioxine, - dibenzofurane ; PPCP : pharmaceuticals and personnal care products ; PFOS : Perfluorooctane sulfonate ; PBB : Polybromobiphenyl; PBT : Persistent, bioaccumulative, toxic ; ED : endocrine disruptor

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O-A3-01-01

A NEW METRIC TO ASSESS SINK LIMITATION OF REGIONAL MATERIAL FLOWS

Ulrich Kral1, Paul H. Brunner1

1 Vienna University of Technology, Institute for Water Quality, Resource and Waste Management, Karlsplatz 13/226, A-1040, Vienna, Austria


The objective of this paper is to present a new indicator for the assessment of substance flows into sinks. The indicator quantifies the environmentally acceptable mass share of a substance in waste and emission flows to sinks, ranging from 0% as worst case to 100% as best case. First, the indicator is defined. Second, a methodology to determine the indicator score is presented, including (i) inventory analysis based on substance flows analysis, and (ii) impact assessment based on a distance-to-target weighting approach. Finally, the metric developed is applied in three case studies including copper (Cu) and lead (Pb) in the city of Vienna, and Perfluorooctane Sulfonate (PFOS) in Switzerland.

The following results are obtained: In Vienna, 99% of Cu flows to geogenic and man-made sinks are in accordance with accepted standards. However, the 0.7% of Cu entering urban soils and the 0.3% entering receiving waters surpass the acceptable level. In the case of Pb, 92% of all flows into sinks prove to be acceptable, but 8% are disposed of in local landfills with limited capacity. For PFOS, 96% of all flows into sinks are acceptable. 4% cannot be evaluated due to a lack of normative criteria, despite posing a risk for human health and the environment. The examples demonstrate the need for appropriate data of good quality to calculate the sink indicator, and for standards needed for the assessment of substance flows to urban soils and receiving waters.

The case studies corroborate that the new indicator is of relevance for (i) managing and controlling waste and emission flows on a regional scale, (ii) monitoring the effectiveness of waste and environmental management for directing flows into appropriate sinks, (iii) comparing different regions, and (iv) for communicating scientific results to decision makers and the public.

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O-A3-01-02

CONVERSION OF SEAWEED DIGESTATE FROM WASTE TO A POTENT BIO-BASED FERTILIZER: SELECTIVE Cd2+ REMOVAL USING CRYOGEL-

SUPPORTED TITANATE NANOTUBES

L. Önnby1,a, I.A. Nges1, B. Mattiasson1 and H. Kirsebom1

1Department of Biotechnology, P.O.Box 124, Lund University, SwedenPresenting author: [email protected]

Marine biomass, e.g. seaweed, is a valuable substrate because it is rich in PO43-, NO3

- and NH4+, in some

trace elements (e.g. K+), in valuable cations Mg2+ and Ca2+), but also in heavy metals such as Cd2+ [1]. The Cd content in seaweed however, renders this biomass as a risky product to use, especially as an end-product as bio-fertilizer for the agricultural sector [2]. To enable seaweed as a bio-based fertilizer, metal ions should ideally be (i) mobilized and thereafter (ii) adsorbed or removed in connection to e.g. biogas production.

In this work, we demonstrate cadmium abatement from a leachate derived from a hydrolysis of seaweed using hydrothermally modified TiO2 particles or titanate nanotubes (TNTs) supported in cryogels [3]. TNTs have been demonstrated to be successful adsorbents for cadmium, but few reports are based on real waste streams. In this study, we focus on the removal of Cd2+ once it is mobilized from the seaweed, and we demonstrate a facile way of implementing TNTs in real systems. The produced TNTs were incorporated in cryogels (TNT-cryo) and in detail characterized. Cryogels is a hydrogel produced at sub-zero temperatures and with a highly interconnected channel system [4], providing an efficient support. In Figure 1, removal of cadmium by TNT-cryo in a particulate-containing leachate derived from hydrolysis of seaweed is shown. In this continuous flow-through process, nearly 1000 ml of leachate by a 0.5 ml monolithic-shaped TNT-cryo, holding 2% (w/v) TNTs, is treated and Cd2+ was removed to more than 95%. Other co-ions were also removed at varied extent. To a lesser degree, valuable cations Ca2+ (14%), NH4

+ (3%), K+ (~10%) whereas NO3- and SO4

2- were removed to a higher extent (~50%). By this process, the seaweed biomass can be further used as a bio-based fertilizer, provided cadmium is reduced in a remediation process providing a selective adsorption similar to what is shown here.

Figure 1. Continuous Cd2+ removal for TNT-cryo in spiked leachate water of 1 mg Cd L-1 at a flow rate of 0.5 ml min-1 in a leachate with total solids of 3.4±0.4%, total suspended solids 7.8±0.2 mg L-1, and volatile solids of 21%. (pH =7.8±0.01, T = 22ºC).

References[1] V.N. Nkemka and M. Murto, Process Biochem. 47(12): p. 2523-2526 (2012).[2] C.. van Netten, et al., Sci Total Environ. 255(1–3): p. 169-175 (2000).[3] A.J. Du, D.D., Sun, J.O., Leckie, J Hazard Mater. 187(1-3):p. 96-100 (2011).[4] H. Kirsebom and B. Mattiasson, Polym Chem. 2(5): p. 1059-1062 (2011).

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O-A3-01-03

SUSTAINABLE DESIGN OF DYE SENSITISED SOLAR CELLS: ISSUES AND OPPORTUNITIES

R. G. Charles1,2, M. L. Davies3, P. Douglas2

1COATED Engineering Doctorate, Swansea University, SA2 8PP, Swansea, UK2Chemistry Group, College of Engineering, Swansea University, SA2 8PP, Swansea, UK

3SPECIFIC, Swansea University, SA2 8PP, Swansea, UKPresenting author: [email protected] / [email protected]

Ten million tonnes of Waste Electrical and Electronic Equipment, WEEE, is generated in the EU per year. Globally, WEEE accounts for 5% of all municipal solid waste, and it is one of the fastest growing waste streams.[1,2] It is a complex heterogeneous mixture of materials including economically and strategically important metals and a variety of toxic heavy metals and persistent organic pollutants. The negative impacts upon human health and the environment resulting from improper treatment of WEEE are wide ranging and can be severe.[3] The rate of WEEE generation also contributes to global resource depletion. In light of this, it is becoming increasingly important to incorporate sustainability consider-ations in the design of future electrical/electronic products to support cradle-to-cradle (C2C) ‘circular economy’ product lifecycles, rather than the current ‘linear economy’ cradle-to-grave approach. Such an approach requires sustainable design, incorporating materials substitution and planning for end of life processing, to enhance potential for reuse, upgrade, refurbishment, repair, and suitability for avail-able or new, customised, recycling processes.

PV products will ultimately become WEEE. Here, we consider the C2C lifecycle approach to the var-ious emerging dye sensitised solar cell (DSC) technologies, which typically use ruthenium complexes, organic dyes, or lead perovskites, to absorb solar radiation.[4-6] Proposed uses of DSCs include both low energy/area applications in consumer products and large scale energy production, such as energy generating cladding for buildings. These different applications create significantly different sustain-ability demands on product design. For all three types of cell, life-cycle issues include the use of EU14 critical materials such as indium and platinum group metals in conducting layers and contacts, issues which may be resolved by ‘materials substitution’. In addition the different materials used in the DSCs create different waste problems which may require different recycling strategies. Specific life-cycle issues associated with ruthenium based DSCs include critical material supply risk and losses; while for lead perovskite sensitisers environmental issues may well be paramount.

There can be significant environmental impacts even for ‘green energy’ technologies. Given the stage of development of DSC technology there is now a window of opportunity to minimise these by C2C design, and consideration of sustainability throughout the entire product life-cycle.

References1. F. O. Ongondo, I.D. Williams, and T.J. Cherrett, Waste Manag. 31, 714 (2011).2. R. Widmer, H. Oswald-Krapf, D. Sinha-Khetriwal et al., Environ. Impact Assess. Rev. 25, 436 (2005).3. B. H. Robinson, Sci. Total Environ. 408, 183 (2009).4. M.K. Nazeeruddin, F. De Angelis, et al., J. Amer. Chem. Soc. 127, 16835 (2005).5. A. Mishra, M. K. R. Fischer, and P. Bäuerle, Angew. Chem. Int. Ed. Engl. 48, 2474 (2009).6. N.-G. Park, J. Phys. Chem. Lett. 4, 2423 (2013).

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O-A3-01-04

THE ROLE OF CLIMATIC FACTORS IN GLOBAL SELENIUM CYCLING

Gerrad D. Jones1, Bas Vriens1,2, Tim Blazina1,2, Markus Lenz3,4, Lenny H.E. Winkel1,2

1Eawag Swiss Federal Institute of Aquatic Science and Technology, 8600 Dübendorf, Switzerland2 Swiss Federal Institute of Technology (ETH) Zurich, 8092 Zurich, Switzerland

3University of Applied Sciences and Arts Northwestern Switzerland, School of Life Science, Institute for Ecopreneurship, CH-4132 Muttenz, Switzerland 3 Department of Environmental Technology,

Wageningen University, 6708 WG Wageningen, The Netherlands Presenting author: [email protected]

Selenium (Se) is an essential element for human health but has a relatively narrow range of recommended daily intake. Globally, Se shows a very irregular distribution in agricultural soils, which is a main factor in widespread Se deficiency: it is estimated that 0.5 to 1 billion people worldwide have too low Se intake [1]. In spite of this major environmental health threat, the processes that control the global distribution of Se are still largely unknown. Even though bedrock is locally an important source of Se into soils it has failed to explain the more widespread low to medium Se levels in soils. Hypothetically, atmospheric input of Se could be an important source of terrestrial Se and help explaining the large-scale spatial distributions of Se in soils [2]. Here we will present new insights into the sources and atmospheric pathways that control these distributions.

The atmosphere is an important transient reservoir for Se, which is fed by volatile Se compounds formed via bioalkylation in both marine [2] and terrestrial [3] environments. In a study conducted in a natural wetland in Switzerland we showed that the average volatile flux of Se from the surface of the peatland is considerable (up to 0.12 μg m-2 day-1) and increases with temperature, which implies that emissions will increase with global warming [3]. The atmosphere can also function as a source of terrestrial Se via atmospheric deposition of which wet deposition is the most important [2]. Using a loess-paleosol sequence from the Chinese Loess Plateau, which is a unique record for continental climate change, we reconstructed atmospheric deposition of Se over the last 7 million years and we could show that in the paleosols, variations in Se concentrations correlate to variability in East Asian monsoon-derived precipitation [4]. This relationship indicates that the intensity of precipitation is an important controlling factor of the terrestrial Se distribution in monsoonal China, where diseases related to severe selenium deficiency occur.

Insights in the role that climate plays on the abundance of Se in the terrestrial environment will pave the way for future predictions of Se distribution patterns based on climate data. These predictions are crucial in the prevention of future health hazards resulting from uneven distributions of Se in the environment.

References1. A. Haug, R.D. Graham, O.A. Christophersen, G.H. Lyons, Microb. Ecol. Health Dis. 19, 209−228

(2007).2. H. Wen, J. Carignan, Atmos. Environ. 41, 7151−7165 (2007).3. B. Vriens, M. Lenz, L. Charlet, M. Berg and L.H.E. Winkel, Nat. Commun. DOI: 10.1038/

ncomms4035 (2014).4. T. Blazina, Y. Sun, A. Voegelin, M. Lenz, M. Berg, and L.H.E. Winkel, Nat. Commun. (in press).

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O-A3-02-01

SPATIAL AND TEMPORAL VARIATION OF POLYCYCLIC AROMATIC COMPOUNDS IN THE ATHABASCA OIL SANDS REGION

RECONSTRUCTED FROM DATED LAKE SEDIMENT CORES

Muir, D.1, J. Kurek2, J. Kirk1, C. Manzano1, M. Evans3, X. Wang1, J. Keating3,J. Smol2

1 Environment Canada, Aquatic Contaminants Research Div., Burlington, ON, Canada2Department of Biology, Queen’s University, Kingston, ON, Canada

3Environment Canada, Aquatic Contaminants Research Div., Saskatoon SK CanadaPresenting author: [email protected]

The Canadian oil sands region contains an estimated 168.6 billion barrels of recoverable bitumen [1], which accounts for 97% of Canada’s petroleum reserves and ranks Canada third globally in terms of domestic oil reserves [2]. In 2013, Canadian oil sands development produced 1.9 million barrels (308,000 m3) per day, consisting of about 50% marketable bitumen and 50% synthetic crude oil. Assessments of the environmental impacts of the Athabasca oil sands development in northeastern Alberta have noted the lack of long-term data and very limited information on pre-impact conditions. In this study, conducted under the Joint Oil Sands Monitoring Program, we have used paleolimnological techniques to reconstruct loadings of Polycyclic Aromatic Compounds (PACs) over the last 50 to 100 years. Dated sediment cores from 19 lakes were analysed; 11 were within about 50 km (near field) of the bitumen upgrading facilities in the development area north of Ft McMurray and 8 at 75-185 km distance (far field). Sixteen lakes were remote, undisturbed and received only atmospheric inputs, while 3 larger far-field lakes, had small communities within their catchments. Total (Σ)PAC (46 analytes) concentrations increased in all near-field lakes, beginning at the early 1970s, particularly C1-C4-alkylated PACs and C1-C4-dibenzothiophenes (DBTs). Maximum post-2000 ΣPAC fluxes were 1.8 to 24-times greater than pre-1960 background levels. Increasing ΣPAC was also evident in far-field lakes although post-2000/pre-1960 enrichment factors were generally much lower (1.0-3.9-fold). C1-C4 alkylated PACs and DBTs, which are prominent PACs in oil sands bitumen, predominated in all samples, representing 55 to 89% and 1.8 to 17% of the ΣPACs, respectively. C3-DBT/C3-phenanthrene and C2-DBT/C2-chrysene ratios, along with other indicators of combustion sources, suggest a shift to petrogenic and unweathered alkylated PAC sources in the modern sediments of near-field cores. Ratios of retene to total unsubstituted PACs were higher in pre-1960 sediments than in the modern sediments in all near-field lakes indicating a greater proportion of wood combustion and terrestrial plant inputs compared with recent times. While ΣPAC have increased markedly since the 1960–1970s, coinciding with over four decades of oil sands development, concentrations of unsubstituted PAC concentrations in sediments remain well below sediment quality guidelines except in one lake near the development.

References1. Energy Resources Conservation Board, 2012. ST98-2012 Alberta’s Energy Reserves 2011 and

Supply/Demand Outlook 2012-2021. http://www.ercb.ca/sts/ST98/ST98-2012.pdf. pp. 290.2. Canadian Association of Petroleum Producers, 2014. Upstream Dialogue - The Facts on Oil Sands.

http://issuu.com/capp/docs/oilsands-fact-book/. 68 pp.

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O-A3-02-02

CARBON DIOXIDE TRIGGERED METAL(LOID) MOBILISATION IN A MOFETTE

J. Mehlhorn1, F. Beulig2, K. Küsel2,3, B. Planer-Friedrich1

1University of Bayreuth, Environmental Geochemistry, Bayreuth Center for Ecology and Environmental Research (BayCEER), 95440 Bayreuth, Germany

2Friedrich Schiller University Jena, Aquatic Geomicrobiology, Institute of Ecology, 07743 Jena, Germany

3German Centre for Integrative Biodiversity Research (iDiv) Halle-Jena-Leipzig, 04103 Leipzig, Germany


Carbon capture and geologic storage is a frequently discussed option to reduce atmospheric CO2 concentrations with the long-term risk of leakage from storage sites to overlying aquifers and soils [1]. As natural analogues to such leakages, we chose cold volcanic CO2 exhalations, so-called mofettes, in a wetland area in the Czech Republic to follow the fate of metal(loid)s under CO2-saturated conditions. Compared to reference fluvisols at the study site, mofette soils were characterised by decreased pH (by 0.5 to 4.9 ± 0.05) and redox potential (by 80 mV to 300 ± 40 mV), as well as accumulation of organic carbon. Poorly and well-crystalline Fe (hydr)oxides, the most important metal(loid) sorbents in the CO2-unaffected soils (7.9 ± 5.9 g kg-1), showed significantly lower concentrations under the acidic and reducing conditions in the mofettes (1.2 ± 0.4 g kg-1). In turn, this increased the mobility of adsorbed As with up to 2.5 times higher concentrations in mofette pore waters (58 ± 18 µg L-1). Arsenic methylation (up to 11 % of total As) and thiolation (up to 9 %) contributed to its net-mobilisation. Dissolved Mn

(131 ± 53 µg L-1), Ni (9.1 ± 3.1 µg L-1) and especially Cu (2.2 ± 1.0 µg L-1) remained low, likely due to complexation and/or adsorption to organic matter and remaining Fe (hydr)oxides. A one-month in situ mobilisation experiment showed mobilisation of all considered elements to the aqueous phase suggesting that desorption is the faster and initially dominating process while resorption is a secondary, slower process. We conclude that the CO2-induced mobilisation of toxic As and net-immobilisation of essential micro-nutrients (Mn, Ni, Cu) (Figure 1) constitute serious risks and should be tested for transferability and relevance at geologic carbon storage sites.

Reference1. Y.-S. Jun, D. E. Giammar, C. J. Werth, and D. A. Dzombak, Environ. Sci. Technol. 47, 1-2 (2013)

Figure 1: Graphical summary of mobilisation and immobilisation processes in a mofette soil (right) compared to a CO2-unaffected reference soil (left).

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O-A4-01-02

OXIDATION OF ALGAL-DERIVED TASTE AND ODOR COMPOUNDS BY FERRATE(VI): REACTION KINETICS AND ELIMINATION

EFFICIENCY

Jaedon Shin, Donghyun Lee, Yunho Lee †

Department of Environmental Science and Engineering, Gwangju Institute of Science and Technology (GIST), 500-712, Gwangju, Republic of Korea


Blooms of cyanobacteria in water resources can generate taste and odor (T&O) compounds, cyanotoxins, and disinfection byproduct precursors, which have been a significant concern to drinking water utilities. T&O compounds can be detected by consumers at very low concentrations (ng/L range) and affect the public’s perception of the safety of drinking water. Thus, effective eliminations of T&O compounds during drinking water treatment are necessary. Chemical oxidation processes such as ozonation or permanganate treatment have been applied to eliminate T&O compounds [1]. In this study, the potential of ferrate(VI) to oxidize T&O compounds during water treatment was assessed by determining rate constants for the reaction of ferrate(VI) with selected T&O compounds. Ferrate(VI) is an emerging water treatment chemical which can be used as both an oxidant and a coagulant [2]. Apparent second-order rate constants (k) were determined in the pH range of 6 to 9 by measuring the decrease of ferrate(VI) concentration in presence of excess T&O compound (i.e., [T&O] >> [Fe(VI)]). The selected T&O compounds containing olefins showed an appreciable reactivity to ferrate(VI). At pH 7, the kapp values were: k1-penten-3-one = 599 M-1 s-1, ktrans,cis-2,6-nonadienal = 160 M-1 s-1, kcis-3-hexen-1-ol = 33 M-1 s-1, kβ-cyclocitral = 46 M-1 s-1, kβ-ionone = 1115 M-1 s-1. Other T&O compounds such as geosmin, MIB, and 2-isopropyl-3-methoxypyrazine showed low reactivity to ferrate(VI) (k < 1 M-1 s-1) due to the absence of electron-rich moieties. Kinetic studies were also performed by measuring the decrease of T&O compound in presence of excess ferrate(VI). Interestingly, the apparent second-order rate constants determined in the ferrate(VI) excess condition increased with increasing ferrate(VI) concentration. For example, the kapp values for cis-3-hexen-1-ol were 71, 298, and 662 M-1 s-1 for the ferrate(VI) concentration of 40, 80, and 120 μM, respectively. The observed enhanced elimination rate of olefinic T&O compounds at higher ferrate(VI) concentration might be attributable to the reaction of perferryl(V) or ferryl(IV) species. These high-valent iron species are produced during ferrate(VI) self-decay and known to be several orders of magnitude more reactive than Fe(VI) [3]. Nevertheless, more in depth studies are necessary to understand the mechanisms. Overall, the kinetic study shows that ferrate(VI) oxidation can be effective to eliminate T&O compounds with olefin moiety. The elimination efficiency of selected T&O compounds during real water treatment with ferrate(VI) will also be presented.

References1. Peter, A. and U. Von Gunten, Oxidation kinetics of selected taste and odor compounds during ozonation of drinking water.

Environmental science & technology, 2007. 41(2): p. 626-631.2. Lee, Y., Zimmermann, S.G., Kieu, A.T., and U. Von Gunten, Ferrate (Fe(VI)) application for municipal wastewater

treatment: a novel process for simultaneous micropollutant oxidation and phosphate removal. Environmental science & technology, 2009. 43: p. 3831-3838.

3. Lee, Y., Kissner, R., U. Von Gunten, Reaction of ferrate(VI) with ABTS and self-decay of ferrate(VI): Kinetics and Mechanisms. Environmental science & technology, 2014. 48: p. 5154-5162.

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O-A4-01-03

ASSESSMENT OF THE REACTIVITY OF ORGANIC COMPOUNDS WITH OZONE IN AQUEOUS SOLUTION BY QUANTUM CHEMICAL

CALCULATIONS: ROLE OF DELOCALIZED AND LOCALIZED MOLECULAR ORBITALS

Minju Lee1, Saskia Zimmermann-Steffens1, J. Samuel Arey1,2, Kathrin Fenner2,3, Urs von Gunten1,2,3

1School of Architecture, Civil and Environmental Engineering (ENAC), École Polytechnique Fédérale de Lausanne (EPFL), CH-1015, Lausanne, Switzerland

2 Eawag, Swiss Federal Institute of Aquatic Science and Technology, Ueberlandstrasse 133, CH-8600 Duebendorf, Switzerland

3Institute of Biogeochemistry and Pollutant Dynamics, ETH Zurich, CH-8092 Zurich, SwitzerlandPresenting author: [email protected]

Ozonation is a promising tertiary wastewater treatment option to eliminate micropollutants such as pharmaceuticals and personal care products present in wastewater effluents prior to its discharge into the aquatic environment. Second-order rate constants (kO3) for the reaction of ozone with micropollutants are essential parameters to determine the optimal ozone dose to achieve a desired elimination efficiency of target micropollutants. A few hundred kO3-values determined experimentally are available in literature [1]. However, there are a number of emerging micropollutants for which kO3-values have not been measured yet and therefore it is difficult to assess the efficiency of ozonation for these compounds. In this study, kO3 prediction models were developed for aromatic compounds, olefins, and amines by correlating logkO3 with quantum molecular descriptors such as the Highest Occupied Molecular Orbital (HOMO) and the Natural Bond Orbital (NBO). Those quantum descriptors were obtained from quantum chemical calculations using the electronic structure software Gaussian 09.C01. Four different levels of theory (HF and B3LYP method coupled with the 6-31G and 6-311++G** basis set) were used for all individual compounds and the polarizable continuum model (PCM) was used as the implicit solvation method throughout the whole calculations. The energy of the HOMO or a MO lower than the HOMO (HOMO-n, n≥0) of aromatic compounds showed good correlations with the corresponding kO3 by dividing them into five different groups, i) phenol derivatives (R2=0.94-~0.95, n=35), ii) benzene dervatives (R2=0.67-~0.78, n=50), iii) aniline derivatives (R2=0.82-~0.86, n=16), iv) mono- and di-alkoxybenzenes (R2=0.80-~0.90, n=17), v) trimethoxybenzenes (R2=0.98-~0.99, n=4). An unsatisfactory correlation was observed for olefins using their HOMO energies. Instead, the kO3-values of olefins turned out to correlate well with the natural bond orbital (NBO) energy of the π bond of the carbon-carbon double bond of olefins calculated by the NBO 3.1 program (R2=0.80-~0.88, n=45). kO3-values of amines were found to be correlating well with the NBO energy of the nitrogen lone-pair electrons (R2=0.81-~0.82, n=59). The performance of the quantum calculation models developed in this study overall turned out to be similar to or better than the quantatitive structure-actitivty relationship (QSAR) models previsouly developed [2] for aromatic compounds (nphenols=28, nbenzenes=21, nanilines=14), olefins (n=40), and amines (n=48).

References1. C. von Sonntag and U. von Gunten. Chemistry of ozone in water and wastewater treatment: From

basic principles to applications (IWA, London 2012).2. Y. Lee and U. von Gunten, Water Res. 46, 6177-6195 (2012).

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O-A4-01-04

SURFACE WATER TREATMENT BY O3 or AOP O3/H2O2: IS A COMPROMISE BETWEEN MICROPOLLUTANTS REMOVAL AND

MITIGATION OF OXIDATION PRODUCTS AND BY-PRODUCTS POSSIBLE?

Marc Bourgin1, Ewa Borowska1,2, Jakob Helbing3, Hans-Peter Kaiser3, Juliane Hollender1,4, Christa S. McArdell1, Urs von Gunten1,4,5

1Eawag, Swiss Federal Institute of Aquatic Science and Technology, CH-8600 Dübendorf, Switzerland2Silesian University of Technology, Environmental Biotechnology Department, PL-44100 Gliwice, Poland

3Zurich Water Works, CH-8021 Zurich, Switzerland4Institute of Biogeochemistry and Pollutant Dynamics (IBP), ETH Zurich, CH-8092 Zurich, Switzerland

5School of Architecture, Civil and Environmental Engineering (ENAC), Ecole Polytechnique Fédérale de Lausanne (EPFL), CH-1015 Lausanne, Switzerland


The combination of O3 and H2O2 is a widely applied advanced ozonation process (AOP), producing highly reactive •OH radicals, to improve water quality at moderate cost compared to other AOPs but more expensive than conventional ozonation.In the present study, Lake Zürich water was spiked with 1 000 ng L-1 of various organic micropollutants presenting wide ranges of applications (pharmaceuticals, pesticides, X-Ray contrast media, artificial sweeteners and industrial chemicals) and ozone reactivity (kO3 <<1 (sucralose) – 106 (tramadol) M-1 s-1)1.The oxidation of micropollutants by either conventional ozonation or the AOP O3/H2O2 was investigated in two pilot plants, a conventional system and an alternative reactor design with a flow of 4 – 5 m3/h. The following parameters were studied: ozone dose (0.5 – 3 mg/L), initial bromide concentration (16 – 200 µg/L), pH (6.5 – 8.5) and O3:H2O2 mass ratio (1:0.35 – 1:3).Water treatment efficiency was evaluated in particular by following the removal of parent compounds as well as the fate of selected transformation products formed during oxidation with online SPE-LC-HRMS analysis2.At optimized conditions, the addition of H2O2 enables to achieve an elimination of chemicals greater than 90% even for the most persistent compounds like sucralose. Simultaneously, the transformation products were significantly abated under these conditions. The production of bromate, a potentially carcinogenic ozonation by-product1, was also followed and could be substantially reduced by more than a factor of 5 by addition of H2O2. This reduction depended on the O3:H2O2 mass ratio.Therefore, though the costs to implement an AOP with O3/H2O2 and a post-treatment step to remove H2O2 residual are significant, the addition of H2O2 in ozone-based oxidation processes was demonstrated to be very beneficial for an enhanced micropollutant removal in drinking water.

References1. C. von Sonntag and U. von Gunten, Chemistry of ozone in water and wastewater treatment (IWA Publishing, London,

2012).2. H. Singer, S. Jaus, I. Hanke, A. Lück, J. Hollender, A.C. Alder, Environ. Poll. 158 (2010) 3054-3064.3. J. L. Acero, K. Stemmler, U. von Gunten, Environ. Sci. Technol. 34 (2000) 591-597.4. S. G. Zimmermann, A. Schmukat, M. Schulz, J. Benner, U. von Gunten, T. A. Ternes, Environ. Sci. Technol. 46 (2011)

876-884.

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O-A4-01-05

EVALUATION OF OZONATION AND PHOTO-FENTON OXIDATION AS POST-TREATMENT FOR TEXTILE WASTEWATER DEGRADATION

M. Punzi1, F. Nilsson2, B.-M. Svensson3, M. Jonstrup4 and B. Mattiasson1

1Biotechnology, Department of Chemistry, Lund University, 22100, Lund, Sweden2Chemical Engineering, Department of Chemistry, Lund University, 22100, Lund, Sweden

3School of Education and Environment, Kristianstad University, Kristianstad, Sweden4Sweco Environment AB, 20122, Malmö, Sweden


Treatment of textile wastewater is challenging because the water contains low- or non-biodegradable compounds such as dyes, detergents, surfactants, biocides and more that are used to improve the textile process and to make the clothes resistant to physical, chemical and biological agents. New technologies have been developed in the last decades and in particular Advanced Oxidation Processes (AOPs) have shown considerable potential for treatment of industrial effluents [1]. In our study, photo-Fenton oxidation and ozonation have been investigated as post-treatment after the anaerobic degradation of raw textile wastewater. The biological treatment consisted of two anaerobic biofilm reactors operated in continuous mode. The average COD reduction in the biological step was 30%, which is in line with the performance of the anaerobic treatment carried on at the full scale plant in Nijverdal, Holland [2]. The performance of the post-treatments has been compared based on their ability to reduce organic content, as COD, and acute toxicity, which was measured using Microtox® and a toxicity test targeting the brine shrimp Artemia salina. The reduction of absorbance at 254 nm was also measured to monitor the degradation of aromatic compounds. The best results were obtained using the anaerobic/photo-Fenton process with an overall 82% reduction in COD compared with an average of 70% reduction achieved using the anaerobic/ozonation process. The ozonation was carried on in batch mode and 4 ozone concentrations were tested by increasing the length of the ozonation from 1 to 6 minutes. No significant correlation was observed between ozone dose and COD reduction, which was unexpected. However, when looking at the amount of ozone actually consumed, it becomes clear that only a fraction of the ozone fed into the reactor could dissolve in the water and contribute to the oxidation of the contaminants. The final COD was 300 mg/L after photo-Fenton and 530 mg/L after ozonation, which underlines the importance of adding an additional polishing step, such as sand filtration or biological activated carbons. The final effluents had lower toxicity than the untreated wastewater, but, interestingly, the effluent treated with photo-Fenton oxidation was more toxic (EC20 33%) than that treated with ozone (EC20 64%) according to the Microtox test, even though the COD removal would suggest the opposite. In contrast, the toxicity test based on Artemia salina showed no toxicity of the treated effluents. The mutagenicity of the untreated and treated wastewater will be measured using Ames test and costs and environmental impact of the two processes will be evaluated. This study shows that physical-chemical processes, such as ozonation and photo-Fenton oxidation, can improve significantly the treatment of textile wastewater by reducing both organic content and toxicity.

References1. I. Oller, S. Malato and J.A. Sánchez-Pérez, Sci Total Environ 409, 4141-4166 (2011).2. C.T.M.J. Frijters, R.H. Vos, G. Scheffer, R. Mulder, Water Res 40, 1249–1257 (2006).

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O-A4-01-06

EFFECTS OF THE WATER MATRIX ON SULFATE RADICAL BASED OXIDATION

Holger V. Lutze1,2, Nils Kerlin1, Rani Bakkour1, Clemens von Sonntag1,3 and Torsten C. Schmidt1,3,4

1 University Duisburg-Essen, Instrumental Analytical Chemistry Universitätsstr. 5, D-45141 Essen, Germany

2 IWW Water Centre, Moritzstr. 26, D-45476 Mülheim an der Ruhr, Germany3Max-Planck-Institut für Bioanorganische Chemie, Stiftstrasse 34-36, P.O. Box 101365, D-45470

Mülheim an der Ruhr4University Duisburg-Essen, Centre for Water and Environmental Research (ZWU) Universitätsstr. 5

D-45141 EssenHolger V. Lutze: [email protected]

The sulfate radical (SO4●─) finds increasing interest in oxidative water treatment since it is capable of

degrading a large number of recalcitrant pollutants [1]. SO4●─ is formed in the photolysis of persulfate

(UV/S2O82─) in analogy to the photolysis of hydrogen peroxide (UV/H2O2) which is yielding ●OH

(advanced oxidation process (AOP)). SO4●─ displays different reaction mechanisms compared to ●OH

and its unique features may complement AOPs. In oxidative processes the influence of main matrix components such as natural organic matter (NOM), bicarbonate and chloride is very important. In that regard, the reaction of chloride plus SO4

●─ is of particular importance since it can significantly influence the oxidation system. This was investigated by comparing the degradation of two model compounds with very different reactions rates towards SO4

●─ (4-nitrobenzoic acid (pNBA k < 106 M-1 s-1 [2]) and 4 chlorobenzoic acid (pCBA, k = 3.6 × 108 M-1 s-1 [2]). However, if UV/S2O8

2─ is applied to river water pNBA and pCBA are degraded at comparable rates (Figure 1), indicating that another reactive species than SO4

●─ prevails. McElroy has shown, that ●OH are formed in the reaction of SO4●─ plus Cl─ at

neutral pH [3]. This may also apply for natural waters containing Cl─ in the mM range. The influence of NOM was also investigated, revealing that UV/S2O8

2─ is more efficient in pollutant degradation than UV/H2O2, since scavenging of SO4

●─ by NOM is weaker compared with ●OH. Furthermore NOM inhibits the formation of the potential carcinogen bromate in UV/S2O8

2─.

Figure 1: Degradation of pCBA and pNBA in UV/S2O82─,

River water (1 mM chloride, 2.45 mg L-1 DOC, 1 mM HCO3

─, pH 7.2)

References1. R. L. Siegrist, M. Crimi, T. J. Simpkin, York Heidelberg Dordrecht London, 2011.2. P. Neta; V. Madhavan, H. Zemel, R. W. Fessenden,. J. Am. Chem. Soc. 99, 1, 163-164 (1977).3. W. J. McElroy, J. Phys. Chem. 94, (6), 2435-2441 (1990).

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O-A4-02-02

PHOTOCATALYTIC DEGRADATION OF PESTICIDES BY DECATUNGSTATE ANION INTERCALATED IN LAYERED DOUBLE

HYDROXIDES PREPARED AS AEROGELS

E. S. Da Silva1,2, Claude Forano2, H. D. Burrows1, M. Sarakha2, P. Wong-Wah-Chung3, V. Prevot2

1Department of Chemistry, University of Coimbra, Rua Larga, 3004-535, Coimbra, Portugal2Clermont Université, Université Blaise Pascal, Institut de Chimie de Clermont-Ferrand, BP

10448, F-63000 Clermont-Ferrande, France3Aix-Marseille Université, Laboratoire Chimie de l`Environnement, Équipe Micropolluants

Organiques, Campus Arbois,13006 Marseille, France Presenting author: [email protected]

Water pollution originating from pesticides is a global threat, with its magnitude increasing day-by-day due to their large-scale use in intensive agriculture. In view of this, providing clean water and a clean environment is a challenging task. The advanced oxidation processes (AOPs) [1], and the branch of heterogeneous photocatalysis in particular, are very promising methods for the elimination of these pollutants due to their oxidizing efficiency even towards traces of the target compounds, leading to total mineralization, or at least to their transformation into more harmless products, allowing also the recovery of the catalyst. Several materials have been used as catalysts, as is the case of the polyoxometalate decatungstate anion (W10O32

4-), which exhibit excellent photocatalytic properties [2]. Layered double hydroxides (LDHs), a class of mineral clays displaying unique anion exchange properties, have application in various different fields, including photocatalysis [3]. In the present work we report the synthesis of LDHs aerogels trough a new simple and ecofriendly strategy, implying a fast coprecipitation combined with CO2 supercritical drying, followed by the intercalation of W10O32

4- into the layered structure through anionic exchange reaction. The photocatalytic activity of this W10O32

4--LDH heterogeneous catalyst was assessed towards photodegradation of the pesticide 2-(1-naphthyl) acetamide (NAD). NAD is a plant growth regulator that has been widely used in agriculture for more than 60 years as a component in many commercial plant rooting and horticultural formulations [4]. The photocatalyst as-prepared was carefully characterized using a large panel of solid state characterization techniques (X-ray diffraction, FTIR, TGA, SEM, etc.) and the influence of different parameters such as amount of catalyst, pH and oxygen concentration on the photocatalytic behavior of NAD were investigated. Under our experimental conditions, NAD was mineralized and the photocatalyst was recycled and reused without any loss of photocatalytic activity over four cycles of degradation, making it a promising catalyst for water treatment.

AcknowledgementsEliana S. Da Silva acknowledges Portuguese FCT (Fundação Ciência e Tecnologia) for PhD grant (SFRH/BD/43171/2008).

References1. R. Andreozzi, V. Caprio, A. Insola, R. Marotta, Catal. Today 53, 51-59 (1999).2. C. Tanielian, Coord. Chem. Rev. 178-180, 1165-1181(1998).3. E. S. Da Silva, V. Prevot, C. Forano, P. Wong-Wah-Chung, H. D. Burrows, M. Sarakha, Environ. Sci Poll. Res., DOI:10.1007/s11356-014-2971-z (2014).4. F. E. Gardner, Proc. Fla. State Hort. Soc. 54, 20-26 (1941).

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O-A4-02-03

INTENSIFICATION OF THE CHEMICAL TREATMENT OF PHARMACEU-TICAL PROCESS WASTEWATERS: CATALYTIC WET OXIDATION WITH

DOE AND IRRADIATION COMBINED WITH WET OXIDATION

Erika Szabados1, Antal Tungler1, Sándor Kemény2

1Centre for Energy Research, Hungarian Academy of Sciences, H-1121 Budapest2Department of Chemical and Environmental Process Engineering, Budapest University of Technolo-

gy and Economics, H-1111 BudapestPresenting author: [email protected]

The tested process wastewaters (PWW) were aqueous solutions generated by the fine chemical, mainly by pharmaceutical companies. Because of their high organic content they cannot be discharged directly into the domestic treatment plants. Significant part of them is sent to incineration, but it isn’t a sustain-able solution. These PWWs could be utilized as carbon source for denitrification process, their volatile content could be separated and utilized also.

The organic content of PWWs is partly easily biodegradable, most of them can be introduced into acti-vated sludge treatment after mixing with domestic wastewater (in high ratio), but their minority inhibit the functioning of the activated sludge even in very small concentrations [1,2].

Chemical oxidation could be an effective method for treating these wastes in order to detoxify them. The appropriate oxidation processes are wet (air) oxidation (WAO), advanced oxidation processes (AOP’s). In this research model and real process wastewaters were tested with CWO (catalytic wet ox-idation) and irradiation combined wet oxidation, in order to reduce their COD value and toxicity [3]. In the first part of the research work the effect of the main parameters on reaction rate has been determined by design of experiments (DOE) technique. The intensification, namely further decrease the tempera-ture and the pressure of the oxidation could be possible by enhancement of the generation of OH rad-icals. For this purpose electron beam irradiation has been applied from a linear electron accelerator, through a titanium window into the reaction mixture being in the autoclave under oxygen pressure. The reaction rate was determined with COD and TOC conversion measurements. Our research had triple aim: optimization of the process, increase the reaction rate and moreover to deduce some mechanistic conclusions.

References

1. A. M. Hosseini, V. Bakos, A. Jobbágy, G. Tardy, P. Mizsey, M. Makó, A. Tungler, Per. Pol. Chem. Eng., 55/1 3-10 (2011)

2. A. M. Hosseini, A. Tungler, V. Bakos, Reac. Kinet. Mech. Cat. 103 251-260 (2011)

3. M. Chamam, Cs. M. Földváry, A. M. Hosseini, A. Tungler, E. Takács, L. Wojnárovits, Rad. Phys. Chem, 81 1484-1488 (2012)

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O-A4-02-04

HIGHLY EFFICIENT AND COMPLETE REDUCTION OF p-NITROPHENOLS BY HETEROSTRUCTURED Au-Fe3O4 NANOCATALYSTS

Ruey-an Doong, Fang-Hsin Lin

Department of Biomedical Engineering and Environmental Sciences, National Tsing Hua University, 30013, Hsinchu, Taiwan


Nitrophenols are one of the most often used chemicals in production of explosives and are easily released to the environment through the improper disposal. The Au-Fe3O4 heterostructures (Fig. 1) are novel nanomaterials with high magnetic property and excellent catalytic activity because of their unique physicochemical and catalytic properties. However, the role of electronic behaviors at the interface between Au and Fe3O4 nanoparticles in the catalytic activity of Au-Fe3O4 nanocatalysts remains unclear and the influence of environmental parameters on the catalytic reduction of p-nitrophenol by Au-Fe3O4 in aqueous solutions has received less attention. This gives a great impetus to develop a systematic study on structure characterization to elucidate the reaction mechanism for p-nitrophenol reduction by Au-Fe3O4 heterostructures in aqueous solutions.

In this study, the catalytic reduction of p-nitrophenol by heterostructured Au-Fe3O4 nanocatalysts using NaBH4 as the reducing agent was investigated in aqueous solutions under various environmental conditions. The electron behaviors at the interface of Au and Fe3O4 nanoparticles were also examined to elucidate the reaction mechanisms for p-nitrophenol reduction. XPS and NEXAS results show that electrons flow is from Au seeds to Fe3O4, and lead to the formation of positively charged Au surface to accelerate the catalytic reduction efficiency and rate of p-nitrophenol. The reduction of p-nitrophenol is a surface-mediated reaction and complete reduction of p-nitrophenol by Au-Fe3O4 heterostructures is oberved under various environmental conditions. The kobs for nitrophenl reduction are in the range 0.61-1.51 min-1. The increase in pH lowers the reduction efficiency and rate of p-nitrophenol and a 2.4-fold decrease in the pseudo-first-order rate constant is observed when pH increases from 5 to 9. In addition, the Au-Fe3O4 nanocatalysts show a good separation ability and reusability which can be repeatedly applied for complete reduction of nitrophenol for at least 6 successive cycles without the loss of saturation magnetization. The possible reaction mechanism for p-nitrophenol reduction by Au-Fe3O4 heterostructures in the presence of NaBH4 is proposed (Fig. 2). Results obtained in this study clearly demonstrate that the Au-Fe3O4 heterostructures are excellent nanocatalysts which can be applied in heterogeneous catalysis, water treatment, and green chemistry.

e-

e-

e-e-

e-

e-electron flow

δ+

δ+

δ+δ+

Fe3O4

AuBH4-

H2 + BO3- e-

H+ +

e-

Fe2+Fe(II)

Fe3+

H2O2

•OH

end products,CO2

Fe(II)

Fe(II)

: Au atom : O atom

: Fe atom

: Surface bound ferrous ion

4-NP 4-AP

Fig. 1. HRTEM images ofAu-Fe3O4 Fig. 2. The Regone plot for as-preparedheterostructures. and CO2-activated HPCMs.

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O-A4-02-05

ZERO VALENT IRON-BASED ADVANCED OXIDATION PROCESSES AS POTENTIAL ALTERNATIVES TO THE CLASSICAL HOMOGENOUS

FENTON TREATMENT OF INDUSTRIAL MICROPOLLUTANTS: A CASE STUDY WITH DIMETHYL PHYTHALATE AND OCTYLPHENOL

POLYETHOXYLATE

I. Arslan-Alaton, T. Olmez-Hanci, K. Temiz, C. Bihter Yazici

Istanbul Technical University, School of Civil Engineering, Department of Environmental Engineering, 34469 Maslak, Istanbul, Turkey

[email protected]

Intensive industrial and urban activities have led to increased pollutant concentrations in water and wastewater, causing serious health-related and ecotoxicological problems in the environment. In the last three decades, Advanced oxidation processes (AOPs) have been developed to treat problematic (toxic, biorefractory) pollutants found in effluent streams. More recently, the use of sulfate radical (SO4

·-)-based AOPs (S2O82-/UV-C, S2O8

2-/Fen+, etc.) and zero-valent iron (ZVI; Fe0) has received global interest and promising treatment efficiencies have been reported so far in the scientific literature. ZVI-based treatment systems have already been applied as alternatives to the more conventional Fenton and Fenton-like processes for the removal of chlorinated organics, nitroaromatic compounds, arsenic, heavy metals, nitrate, industrial dyes, and phenols. ZVI is reactive (RP=-0.44 eV), non-toxic, abundant, cheap, relatively easy to produce and its treatment applications require little maintenance. ZVI is capable of oxidizing pollutants by an electron transfer mechanism; however, for harsher conditions, ZVI treatment has to be enhanced chemical or thermally. In the present study, two industrial micropollutants (dimethyl phthalate-DMP; octylphenol polythoxylate-OPPE) were chosen as model contaminants and subjected to nano-sized ZVI treatment under varying reaction conditions for 20 mg/L aqueous pollutant. DMP is a common representative of di-alkyl phthalate esters being classified as an endocrine-disrupting and priority pollutant by various environmental agencies, whereas the nonionic surfactant OPPE has been widely used in the formulations of detergents, emulsifiers, wetting agents, solubilizers and dispersants. The fate of OPPE metabolites is of main concern since they can mimic natural hormones in aquatic organisms, wildlife and even humans. Our treatment results have indicated that (i) no removal of DMP/TOC was observed with 1 g/L ZVI at different treatment pH’s (3-5-7-9); (ii) no DMP/TOC removal was observed at pH 5 and different ZVI concentrations (0.25-0.5-1.0-2.5 g/L); (iii) 29% TOC removal occurred after 40 min treatment levelling off until 120 min in the presence of 2.5 mM persulfate-PS (1 g/L ZVI at pH 5). In the case of OPPE, (i) highest OPEO/TOC removal (10%) in the absence of PS was achieved at pH 5 with 1 g/L ZVI among 0.25-0.5-1.0-2.5 g/L after 60 min; (ii) OPEO/TOC removal decreased only at pH’s above 7 (from 19-22% at pH 3-7 to 3% at pH 9), in the presence of 2.5 mM PS after 60 min treatment; (iii) highest OPEO/TOC removal (33%) was obtained in the presence of 2.5 mM PS and 1 g/L ZVI at pH 5 after 60 min. In the absence of ZVI, 17% TOC removal was obtained for 20 mg/L OPEO with 2.5 mM PS after 60 min treatment at pH 5. Changes in acute toxicity will be examined for the selected ZVI-based treatment processes by two different bioassay protocols employing the photobacteria Vibrio fischeri and the freshwater algae Pseudokirchneriella subcapitata.

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O-A4-02-06

PERFORMANCES OF MODIFIED CERIA-ZIRCONIA NANOMATERIALS FOR THE DEGRADATION OF ORANGE II DYE IN

PRESENCE OF H2O2

H. Issa Hamoud, B. Azambre, G. FinqueneiselUniversité de Lorraine - Laboratoire de Chimie et Physique Approche Multi-échelle des Milieux

Complexes (LCPA2MC) – EA 4632, Institut Jean Barriol– Rue Victor Demange, 57500 Saint Avold, France

[email protected].

The need of more efficient processes for the oxidation of contaminants in wastewaters, has led many researchers to design new Fenton systems based on heterogeneous solid catalysts and H2O2 [1]. Ceria based ones have also attracted some attention due to their unique redox properties and oxygen storage capacity (OSC) [2, 3].

In the present work, the structural and chemical parameters affecting the reactivity of non-sulfated and sulfated commercial ceria-zirconia (CexZr1-xO2) nanomaterials with varying CeO2 content (x = 1, 0.80, 0.50, 0.21, 0) towards the adsorption and degradation of Orange II dye have been evaluated. Characterization of the nanomaterials was performed using nitrogen adsorption (at 77K), XRD, Raman, XPS, TGA and DR-UV-Vis spectroscopy. Briefly, it can be deduced that the sulfation treatment mostly affects the Ce-rich catalysts by increasing the crystallite size and lowering the specific surface area. It is shown that the adsorption of the anionic dye is highly pH-dependent and proceeds via electrostatic interactions with surface cationic Ce and Zr metal centers in acidic medium. On the other hand, H2O2 dissociates on Ce(III) surface sites to yield peroxide-like species. Catalytic tests performed under illuminated or dark conditions indicated that the discoloration rates of Orange II strongly depend on the composition of mixed-oxides. Pure ceria and Ce-rich mixed oxides exhibit the best catalytic activity. Hence, it is proposed that the formation of surface peroxides on Ce(III) defective sites are directly involved into the production of active radical species, which are further promoted by the presence of UV radiation. Though peroxides are rather stable in the absence of organic compounds, it is suggested that they form a reactive complex with the dye on the catalyst surface, this being one of the first step of the discoloration/degradation process. By contrast, the sulfation treatment is unfavorable for H2O2 adsorption, because of the cerium centers inhibition by stable surface sulfates, overall resulting in a reduced catalytic activity, especially for CeO2.

Keywords : peroxide species, direct sulfation, AOP, Fenton, solid solution.

References:[1] L. Marçal, E.H. Faria, M. Saltarelli, P.S Calefi, E.J. Nassar, K.J. Ciuffi, Ind. Eng. Chem. Re. 50, 239-246 (2011).

[2] E.G. Heckert, S. Seal, W.T. Self, Environmental Science & Technology 42, 5014-5019 (2008).

[3] A. Westermann, B. Azambre, Catalysis Today 176, 441-448 (2011).

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O-A4-03-02

OZONATION OF CETIRIZINE - KINETICS AND DETERMINATION OF TRANSFORMATION PRODUCTS

Ewa Borowska1,2, Marc Bourgin1, Juliane Hollender1,3, Christa S. McArdell1, Urs von Gunten1,3,4

1Eawag, Swiss Federal Institute of Aquatic Science and Technology, CH-8600 Dübendorf, Switzerland

2Silesian University of Technology, Environmental Biotechnology Department, PL-44100 Gliwice, Poland

3Institute of Biogeochemistry and Pollutant Dynamics (IBP), ETH Zurich, CH-8092 Zurich, Switzerland

4School of Architecture, Civil and Environmental Engineering (ENAC), Ecole Polytechnique Fédérale de Lausanne (EPFL), CH-1015 Lausanne, Switzerland

The efficiency of ozonation for the removal of many micropollutants from water is already proven. However, the list of emerging contaminants is growing and their fate during ozonation is still unknown. The development of analytical tools like HR-MS/MS made the detection and identification of these substances as well as their transformation products more efficient. Cetirizine, an antihistamine drug, is usually not completely removed by conventional wastewater treatment and significant concentrations were observed in aquatic environment- up to 220 ng/L in the wastewater effluent and up to 9 ng/L in the river [1]. The aims of this study are (i) to measure the ozone reactivity of cetirizine and (ii) to identify the ozonation products (OPs) formed during the reaction with ozone using both suspect and non-target approaches. The ozone reactivity of the compound was assessed by determining the ozonation rate constant. Considering the structure of cetirizine, a competition kinetic method was chosen [2]. By comparison of the decay of both cetirizine and a competitor (here carbamazepine) under different ozonation conditions, the second-order rate constant was calculated to be 2.1x105 M-1s-1 at pH 7. For the determination of ozonation products, aqueous solutions of cetirizine were ozonated under different compound-to-ozone molar ratios, ranging from an excess of compound (2:1) to an excess of ozone (1:10) in presence of tertiary butanol as a hydroxyl radical scavenger at pH 7 to guarantee only direct ozone reactions. Subsequently the OPs were detected by Liquid Chromatography coupled with a Q-Exactive High-Resolution Mass Spectrometer (ThermoScientificTM). MS data were collected using full scan mode (60-700 m/z) at 70,000 resolution and data-dependent MS2 mode at 17,500 resolution, with both positive and negative electrospray ionization. By comparison of treated samples (spiked and ozonated) with control samples (spiked and non-ozonated) using the SIEVETM software (ThermoScientificTM), the peaks potentially corresponding to OPs can be selected. The MS2 spectra of detected peaks were subsequently analyzed to propose the structure of OPs, including expert knowledge on ozone reaction mechanisms. So far, 14 cetirizine ozonation products have been detected and 3 of them could be confirmed with commercial standards. For the others, structures can be proposed and a general cetirizine ozonation pathway can be formulated.

References1. J. Kosonen and L. Kronberg, Environ. Sci. Pollut. Res. 16, 555-564 (2009).2. C. von Sonntag and U. von Gunten, Chemistry of ozone in water and wastewater treatment

(IWA Publishing, London, 2012).

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O-A4-03-03

DEGRADATION OF ATRAZINE DURING ADVANCED OXIDATION PROCESSES AND FORMATION OF TOXIC TRANSFORMATION

PRODUCTS

Sebastien Allard1, Francesco Busetti1, Janet Y.M. Tang2, Jeffrey W.A. Charrois1, Beate I. Escher.2,3

1Curtin University, CWQRC, GPO Box U1987, Perth WA 6845, Australia 2The University of Queensland, National Research Centre for Environmental Toxicology (Entox), 39

Kessels Rd, Brisbane Qld 4108, Australia 3 Helmholtz Centre for Environmental Research GmbH – UFZ, Permoserstraße 15, 04318 Leipzig,

GermanyPresenting author: [email protected]

Advanced oxidation processes are designed to efficiently remove micropollutants that are refractory to usual drinking water treatment. Even by advanced oxidation, full mineralisation to carbon dioxide is not realistic and transformation products (TPs) are formed. To date, little is known on the identity of the TPs and their relative toxicity.

In this study, water sampled post reverse osmosis in an advanced water treatment plant was spiked with atrazine and treated by UV/H2O2 as well as other common tertiary treatments (UV, ozone and ozone with t-BuOH to quench the OH radical for comparison). The main TPs were identified by liquid chromatography high-resolution mass spectrometry (Orbitrap) and the degradation of atrazine quantified in parallel with a bioanalytical assessment of the reaction mixture using a battery of toxicity tests. The bioassays applied were the Microtox assay for cytotoxicity, the chlorophyll fluorescence assay (IPAM) for photosynthesis inhibition and the AREc32 assay for oxidative stress response.

Results showed that atrazine was efficiently degraded by OH radicals as confirmed by the UV/H2O2 and ozone experiments (Figure 1). Degradation of atrazine led to the formation of multiple TPs. They were identified through high resolution MS2 and MS3 and molecular structure were proposed.

Figure 1: Comparison of different tertiary treatment on the degradation of atrazine and on the mixture effect

The photosynthesis inhibition in green algae was assessed as target effect for herbicides. As expected the inhibitory effect on photosynthesis decreased with the degradation of the atrazine. In contrast, the cytotoxicity and the oxidative stress response remained constant or even increased in the case of UV/H2O2 despite disappearance of atrazine (Figure 1), indicating that the transformation products mixtures exhibit equal or higher toxicity compared to atrazine. The identified TPs have similar structure as atrazine, therefore the mixture effect on the toxicity results are easily justified. This study demonstrated the relevance of toxicity related to the formation of TPs which suggests that the TPs have to be included in the risk assessment of advanced oxidation processes.

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O-A4-03-04

OXIDATION OF ENROFLOXACIN WITH PERMANGANATE: KINETICS, IDENTIFICATION OF OXIDATION PRODUCTS AND DETERMINATION OF

RESIDUAL ANTIBACTERIAL ACTIVITY

Yongpeng Xu1,2, Shiyao Liu1,2, Fuyi Cui.1,2

1State Key Laboratory of Urban Water Resource and Environment, Harbin Institute of Technology, 150090, Harbin, China

2School of Municipal and Environmental Engineering, Harbin Institute of Technology, 150090, Harbin, China


Potassium permanganate [Mn(VII)] Chemistry Oxidation of fluoroquinolone antibiotic enrofloxacin in water is investigated with respect to the kinetics, the mechanisms on the oxidation and the evaluation of residual antibacterial activity after oxidative treatment. High-resolution and high-accuracy Accurate-Mass Quadrupole Time-of-Flight mass spectrometry coupled to high performance liquid chromatograph was used to determine the accurate mass of the measured degradation products. Four main and four minor oxidation products were identified at neutral pH. An oxidation with Mn(VII) pathway for enrofloxacin is proposed. The oxidation took place at the piperazine ring, at which the C-H adjacent to the amine group was attacked by Mn(VII) [1]. Structural changes to the piperazine ring include N-dealkylation, hydroxylation and hydrolysis. The quinolone core remained intact and, defluorination and structural changes to cyclopropyl group were not observed [2]. Residual antibacterial activity of the oxidative reaction solutions against nonresistant Escherichia coli (G-) reference strain DH5ɑ is evaluated by means of quantifying bacterial colonies. It is noticed that the oxidation products exhibited reduction in antibacterial activity comparing to their precursor. The relationship between antibacterial activity and chemical substituent on quinolone ring was assayed, the substituent at carbon-7 is the binding site to enzyme, which significantly affected the activity against Gram negative bacteria [3].

References1. E. T. Denisov and I. B. Afanas’ev, Oxidation and Antioxidants in Organic Chemistry and Biology

(Taylor & Francis Group, U.S., 2005).2. X. V. Doorslaer, K. Demeestere et al, Applied Catalysis B: Environmental 138-139, 333-341 (2013).3. P. C. Sharma, A. Jain, and S. Jain, Acta. Pol. Pharm 66, 587-604 (2009).

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O-A4-03-05

APPLICATION OF ADVANCED OXIDATION PROCESSES IN THE TRANSFORMATION OF ENDOCRIN DISRUPTING PHENYLUREA

HERBICIDES - TOXICOLOGY ASPECTS

G. Simon1, K. Kovács2, T. Alapi1,3, J. Farkas, G. Veréb1, K. Gajda-Schrantz1, A. Dombi1 K. Hernádi1 M. Radács4, Zs. Molnár4, M. Gálfi4

1University of Szeged, Institute of Material Sciences and Engineering, H-6725 Szeged, Tisza Lajos Krt. 103.

2Institute of Isotopes of the Hungarian Academy of Sciences, H-1525 Budapest, P.O.Box 77. 3University of Szeged, Department of Inorganic and Analytical Chem., H-6701 Szeged, P.O.Box 440

Hungary4University of Szeged, Faculty of Juhász Gyula Education, Department of Environmental Biology and

Education, H-6725 Szeged, Boldogasszony sgt. 6.Presenting author: [email protected]

We live in a world in which man-made chemicals have become a part of everyday life. Some of these chemical pollutants can affect the endocrine (hormonal) system and interfere with important developmental processes in humans and wildlife. Close to 800 chemicals are known or suspected to be capable of interfering with hormone receptors, hormone synthesis or hormone conversion. The effects of EDC are not detectable in subtoxic dose in acute experiments. However, these changes can already notice by the chronic treatment with extreme low doses of EDC. Endocrine disrupting chemicals (EDCs) are groups of emerging contaminants that have been detected at trace concentrations in waters around the world. The convencional water treatment technologies are not able to eliminate these trace compounds from waters, thus additional technologies are suitable. Advanced oxidation processes (AOPs) are technologies with significant importance in environmental restoration applications. The AOPs are defined as processes involving the generation of highly reactive oxidizing species able to attack and degrade organic substances. In this work, the efficiency of the various advanced oxidation processes (UV-induced photolysis, heterogeneous photocatalysis, ozonation) and their combinations were investigated an compared in several aspects (initial rate of transformation, rate of mineralization, dehalgenization, and toxicocogy aspects) in the decomposition of diuron, monuron and phenuron, which are suspected endocrin disrupting chemicals and widely used pesticides.In our work toxicology measurements were carried out by different ways. The ecotoxicity tests were done on Selenastrum capricornutum microalgae culture, Daphnia magna zooplankton and bioluminescence inhibition assay using the marine bacterium Vihrio fischeri as the test organism. Another aim of this work was to investigate the neuroendocrine homeostatic effects of EDC agents on in vitro neuroendocrine cell culture modell systems. Our results showed that these EDC agents alone are ineffective on the monoamine activated hormone release (arginine-vasopressin). If the EDC agents were applied with monoamine active compounds together, these effects were significantly.

AcknowledgementsThis research was supported by the European Union and the State of Hungary, co-financed by the European Social Fund in the framework of TÁMOP-4.2.4.A/ 2-11/1-2012-0001 ‘National Excellence Program’. Financial help of the Társadalmi Megújulás Operatív Program (TÁMOP-4.2.2.A-11/1/KONV-2012-0047) also highly appreciated.

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O-A4-03-06

OZONATION OF RANITIDINE UNDER VARIOUS PHYSICOCHEMI-CAL CONDITIONS. DEGRADATION KINETICS AND INTERMEDIATE

BY-PRODUCTS

Christophoros Christophoridis1, Nikolaos Thomaidis1

1Laboratory of Analytical Chemistry, Department of Chemistry, National and Kapodistrian University of Athens, Zografou, Athens 15771, Greece, [email protected]

Ranitidine is pharmaceutical compound, widely used for the treatment of ulcer and other gastroin-testinal conditions. Its occurrence in surface waters and wastewater has been established. Ozonation can be a useful technique for the degradation of ranitidine in water, since molecular ozone selectively attacks organic compounds with high electron density functional groups, such as double bonds, acti-vated aromatic rings or deprotonated amines. The objectives of this study was to assess the effects of various operational parameters (pH, ozone concentration, presence of hydroxyl radical scavengers, matrix effects and natural organic matter) on the kinetics of the ozonation process and to identify and elucidate the structure of intermediate oxidation by-products of ranitidine in aqueous solutions during the ozonation process. Results proved the high reactivity of ranitidine with molecular aqueous ozone with half-life times ranging 0.3-0.5 min. Reaction kinetics are greatly influenced by the initial ozone concentration, with ranitidine removal higher than 80% observed at initial ozone concentrations above 5 mg L-1. As expected, pH was a significant process parameter, with increased values enhancing degra-dation kinetics and overall percentage of mineralization. Pseudo-first-order reaction constants ranged 0.19-6.06 min-1 and the highest values were observed at lower initial ranitidine concentrations and alkaline solutions. At low pH mineralization was limited, while at pH 10, mineralization reached 68%. Water that included cations and ions such as chlorides, bicarbonates, sodium and calcium, tended to decrease the overall ranitidine removal. NOM acted antagonistically, consuming ozone and limiting its overall degradation. Hydrolysis of ranitidine at different pH was limited and this minimal degradation occurred only in extended time periods (>2 days). Furthermore, the main intermediate byproducts of ozonation degradation were identified and structurally elucidated using liquid chromatography coupled to quadrupole-time-of-flight tandem mass spectrometry (HPLC-QqTOF-MS/MS). After background subtraction, selected chromatographic peaks were analyzed and possible molecular formulas based on their exact m/z values were proposed. MS/MS data in relation to various databases were employed in order to tentatively identify intermediate by-products. Proposed by-products showing lowest error (ppm) and highest identification score (including isotopic pattern), along with their chemical structures, include sulfoxide C13H22N4O4S, imine C13H21N3O2S and nitrocompound C4H10N3O2 indicating a direct attack of the molecular ozone to the sulfur and amine group of the compound.

AcknowledgmentsThis research has been co-financed by the European Union and Greek national funds through the Oper-

ational Program “Education and Lifelong Learning” of the National Strategic Reference Framework (NSRF) – ARISTEIA 624 (TREMEPOL project).

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O-A4-04-02

DEVELOPMENT OF A SELF-CONTAINED, PV-POWERED DOMESTIC TOILET AND ELECTROCHEMICAL WASTEWATER TREATMENT

SYSTEM

Michael R. Hoffmann

Environmental Science & EngineeringLinde-Robinson Labs, California Institute of Technology

Pasadena, California 91125 [email protected]

The Hoffmann research group has developed a transportable prototype designed for the treatment of raw domestic wastewater, human urine, human feces, and synthetic human waste analogues. After several hours of PV-powered electrochemical treatment, the turbid, black-water influent can be clarified with the elimination of the suspended particles along with the reduction or total elimination of the chemical oxygen demand (COD), total enteric coliform disinfection via in situ reactive chlorine species generation, and the elimination of measurable protein after 3 to 4 hours of PV-powered treatment. Our advanced prototype incorporates additional features such as a residual sludge handling unit, a hydrogen purification and filter system, and a closed-loop water reuse system for flushing water. We have packaged our second-generation prototypes into modified shipping containers are ready for field-testing in remote locations that lack traditional urban infrastructure. Extensive field-testing in India began in April 2014.

DEVELOPMENT OF A SELF-CONTAINED, PV-POWERED DOMESTIC TOILET

AND ELECTROCHEMICAL WASTEWATER TREATMENT SYSTEM Michael R. Hoffmann

Environmental Science & Engineering Linde-Robinson Labs, California Institute of Technology

Pasadena, California 91125 USA [email protected]

The Hoffmann research group has developed a transportable prototype designed for the treatment of raw domestic wastewater, human urine, human feces, and synthetic human waste analogues. After several hours of PV-powered electrochemical treatment, the turbid, black-water influent can be clarified with the elimination of the suspended particles along with the reduction or total elimination of the chemical oxygen demand (COD), total enteric coliform disinfection via in situ reactive chlorine species generation, and the elimination of measurable protein after 3 to 4 hours of PV-powered treatment. Our advanced prototype incorporates additional features such as a residual sludge handling unit, a hydrogen purification and filter system, and a closed-loop water reuse system for flushing water. We have packaged our second-generation prototypes into modified shipping containers are ready for field-testing in remote locations that lack traditional urban infrastructure. Extensive field-testing in India began in April 2014.

Figure 1: Caltech pre-alpha prototype on display in New Delhi, India. The unit combines a toilet room and an integrated, self-contained, PV-powered-electrochemical treatment system in which the treated water is used as flushing water.

Figure 1: Caltech pre-alpha prototype on display in New Delhi, India. The unit combines a toilet room and an integrated, self-contained, PV-powered-electrochemical treatment system in which the treated water is used as flushing water.

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O-A4-04-03

COMPARATIVE STUDY OF DIFFERENT UV TYPES (UV-C, UV-B, AND UV-A) INDUCED PHOTOLYSIS OF A NEW Β-BLOCKER (NEBIVOLOL)

IN AQUEOUS SOLUTION

A.Salma1, T.C. Schmidt2, J. Tuerk1.1 Institute of Energy and Environmental Technology e.V. (IUTA), 47229 Duisburg, Germany

2 Instrumental Analytical Chemistry, University of Duisburg-Essen, Universitätsstr. 5, 45141 Essen, Germany


Advanced oxidation processes (AOPs) using ultraviolet (UV) light alone or in combination with other oxidizing agents (e.g. TiO2, hydrogen peroxide, Fenton’s reagent etc.) have recently emerged as an im-portant class of technologies for water treatment [1]. Such processes involve the in-situ generation of powerful oxidants such as the hydroxyl radical (HO•) which accelerate the degradation of a wide range of organic contaminants in polluted water [2]. In UV direct photolysis the pollutant to be destroyed will absorb the incident radiation and undergo degradation after excitation from the ground state to its excited state. The efficiency of photodissociation strongly depends on the light absorption event, thus limiting the industrial application of the UV photolytic process compared to the hydroxyl radical driven technologies, where the light absorption by the target pollutant is not required.

However, there are many cases where the target pollutants are strong absorbers of UV radiation, and therefore their UV photolysis may become a significant component during the treatment by UV-driven AOP. There are cases when the pollutant can be treated by both direct photolysis and (HO•) radical induced processes. In such cases, the optimization of the treatment process is driven by economic con-siderations.

The overlap of the UV radiation range with the target pollutant absorption range and the electrical ener-gy efficiency of the different UV lamps play a crucial role in the usage of AOPs [3]. Therefore, the main aim of this work is to provide insight into the effectiveness of different types of ultraviolet radiation (UV-C, UV-B and UV-A) on the photodissociation of Nebivolol, a new pharmaceutical compound from the β-blocker group. The understanding of the overall kinetic behavior of Nebivolol degradation (i.e. zero or first order) is necessary for describing meaningfully the degradation mechanism in a wastewater stream. The photochemical degradation reaction of Nebivolol was examined and compared based on the fluence-based kinetic and electrical energy efficiency per order of magnitude of removal (EEO). The degradation rates and efficiencies were compared in the presence and absence of (HO•) radical scavengers in order to propose the main photodegradation pathway, namely direct UV photolysis or (HO•) radical oxidation reaction. The photolytic reactions were also conducted with Nebivolol contain-ing wastewater treatment plant effluent in order to have an overview of the wastewater matrix effect on the degradation rate. Liquid chromatography tandem mass spectrometry and high resolution mass spectrometry were used to identify transformation products at specific degradation times.

References1. A. Vogelpohl, S. M. Kim, J. Ind. Eng. Chem.10, 33-40 (2004).2. I. H. Kim, N. Yamashita, Y. Kato, H. Tanaka, Water Sci. Technol. 59, 945-955 (2009).3. Z. Q. Shu, J. R. Bolton, M. Belosevic, M. G. El Din, Water Res.47, 2881-2889 (2013)

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O-A4-04-04

PHOTOCATALYTIC DEGRADATION OF MICROCYSTIN-LR UNDER VISIBLE LIGHT USING DOPED TiO2

T. Fotiou 1, T. Triantis 1, T. Kaloudis 2, A. Hiskia 1

1 NCSR ‘‘Demokritos’’, 15341, Athens, Greece2 EYDAP SA, 11146, Athens, Greece


Microcystins ( MCs) are a group of cyclic heptapeptide hepatotoxins that are produced by various cyanobacteria genera. MCs contain three D-amino acids, alanine (Ala), methylaspartic acid (MeAsp), and glutamic acid (Glu), two unusual amino acids, N-methyldehydroalanine (Mdha) and 3-amino-9-methoxy-2,6,8-trimethyl-10-phenyldeca-4,6-dienoic acid (Adda), and two variable L-amino acids (X and Y). The Adda is the amino acid responsible for their toxicity. Microcystin-LR (MC-LR) is the most studied derivative of MCs due to its frequent appearance in water resources and toxicity. Photocatalysis in the presence of TiO2/UVA appears to effectively degrade MC-LR through the formation and decay of several intermediates prior to mineralization [1]. Degradation pathways have been presented [2, 3] with hydroxyl radical (HO•) being the main oxidative species. Even though TiO2 exhibit high efficiency under UVA light, its activation to visible light can facilitate the development of remediation processes replacing the costly facilities for UV light generation. In this study, the photocatalytic degradation of MC-LR is reported using C-doped TiO2 (Kronos vlp-7000) under visible light. C-doping involves substitution of oxygen by carbon atoms producing new energy states deep in the TiO2 band gap, which are responsible for the visible light absorption. Upon TiO2 photocatalysis, excitation of electrons (e-) from the valence to the conduction band leads to the formation mainly of holes (h+), HO• and superoxide radicals (O2

•−). Although the mechanism followed under UV light is well studied, limited information is available concerning the mechanism under visible light photocatalysis [4]. Contribution of those reactive oxygen species (ROS) in the process of photodegradation under visible light was defined using a variety of scavengers (superoxide dismutase, catalase, KBr, MeOH, p-Benzoquinone) specific for different radicals. The transformation products were found to be m/z 795, m/z 835, m/z 1011.5 and m/z 1029. Product with m/z 1029 is a dihydroxylation product (possibly formed though reaction with O2

•−) with the most intense peak. Formation of m/z 1011.5 intermediate (monohydroxylation, from HO• attack) is evidenced after an induction period. Also products with m/z 795 and m/z 835 could be formed after O2

•− addition followed on either of the double bonds of Adda amino acid and by cleavage and formation of carbonyl compounds. Results showed that O2

•− seems to play a key role in the process.

References1. T. Triantis, T. Fotiou, T. Kaloudis, A. Kontos, P. Falaras, D. Dionysiou, M. Pelaez and A. Hiskia, J. Haz. Mat. 211, 196 (2012).2. T. Fotiou, T. Triantis, T. Kaloudis and A. Hiskia, Ind. Eng. Chem. Res. 52, 13991 (2013).3. A. Hiskia, T. M. Triantis, M.G. Antoniou, A. De La Cruz, K. O’Shea, W. Song, T. Fotiou, T. Kaloudis, X. He, J. Andersen and D.D. Dionysiou, Transformation Products of Emerging Contaminants in the Environment: Analysis, Processes, Occurrence, Effects and Risks, Chapter 23 p.687 (Wiley, 2013).4. J. Andersen, C. Han, K. O’Shea and D. Dionysiou, App. Catal. B: Envir. 259, 154–155 (2014)

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O-A4-04-05

KINETIC AND PRODUCT STUDIES OF THE FERRATE(VI) INDUCED OXIDATION OF MICROCYSTIN-LR

Kevin E. O’Shea1, Dionysios D. Dionysiou2, Wenjun Jiang1, Long Chen3, Sudha Rani Batchu1, Piero

R. Gardinali1 and Virender K. Sharma3

1Department of Chemistry and Biochemistry, Florida International University,11200 SW 8th St. Miami, Florida 33199

2Environmental Engineering and Science Program, University of Cincinnati705 Engineering Research Center, Cincinnati, OH 45221-0012

3Department of Environmental and Occupational Health, School of Rural Public Health,Texas A&M University, 1266 TAMU, College Station, Texas 77843-1266


The presence of microcystin-LR (MC-LR) a potent hepatotoxin produced by blue green algae in drinking water sources, is a serious threat to human health. The consumption of MC contaminated water can lead to serious liver damage and related disorders. We have demonstrated a number of hydroxyl radical mediated processes can effectively decompose and detoxify microcystins (1-4). The current study involves the use of ferrate, Fe(VI), an environmental friendly oxidant, as a potential biocide and coagulating agent for MC producing cultures and as an effective oxidant for MC. The addition of ferrate (K2FeVIO4, Fe(VI)) to a MC-LR producing culture kills the culture, which can result in the release of MC-LR from the cells. The levels of MC following Fe(VI) treatment were measured at different growth stages after treatment. The chemical kinetics for the ferrate(VI) (FeVIO4

2-, Fe(VI)) oxidation of MC-LR and model compounds (sorbic acid, sorbic alcohol, and glycine anhydride) were measured over a range of solution pH. The second-order rate constants (k) for oxidation of MC-LR decreased with increase in pH in basic medium as follows from 1.35±0.10 ×102 M-1s-1 at pH 7.5 to 8.08 ±0.08 M-1s-1 at pH 10.0. Product studies using LC/HR-MS/MS indicate the oxidation products involve primarily hydroxylation likely of the benzene ring and olefinic and diene double bonds. Hydrolysis of peptide bond of MC-LR is also proposed. While a number of the Fe(VI) mediated products are analogous to those produced by hydroxyl radical mediated oxidation we have demonstrated hydroxyl radical is not produced during Fe(VI) treatment. The protein phosphatase (PP1) activity of the treated MC-LR solution demonstrates the MC-LR biological activity is readily eliminated by ferrate treatment. Environmental factors can have negative impacts of the effectiveness of oxidative treatments. The presence of carbonate ions in water has minimal effect on the degradation efficiency under our experimental conditions. However the presence of fulvic acids(≥ 0.4 mg L-1) decreases the removal efficiency and higher Fe(VI) dosages would likely be required to effectively treat MC-LR in natural waters.References1) Virender K. Sharma, Theodoros M.Triantis, Maria G. Antoniou, Xuexiang He, Miguel Pelaez,

Changseok Han, Weihua Song, Kevin E. O’Shea, Armah A. de la Cruz, Triantafyllos Kaloudis, et al Separation and Purification Technology 91, 3-17, 2012.

2) J Andersen, C Han, K O’Shea, DD Dionysiou, Applied Catalysis B: Environmental 154, 259-266, 2014.

3) Weihua Song, Tielian Xu, William J. Cooper, Dionysios D. Dionysiou, Armah A.de la Cruz, Kevin E. O’Shea, (Environ. Sci. Technol. 43(5), 1487-1492, 2009.

4) Weihua Song, Kevin E. O’Shea and Patrick Walsh, (Toxicology and Applied Pharmacology 220, 357-363, 2007.

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O-A4-05-02

A NEW TRICHLORAMINE ANALYSIS METHOD, FACTORS INFLUENCING ITS CONCENTRATION IN POOL WATER AND THE EFFECT OF UV

TREATMENT

F. Soltermann1,2, T. Widler1, S. Canonica1 and U. von Gunten1,2,3

1Eawag, Swiss Federal Institute of Aquatic Science and Technology, 8600 Dübendorf, Switzerland2Institute of Biogeochemistry and Pollutant Dynamics, ETH Zürich, 8092 Zürich, Switzerland

3School of Architecture, Civil and Environmental Engineering, EPF Lausanne, 1015 Lausanne, Switzerland


Trichloramine is a problematic disinfection by-product in indoor pool facilities representing a health risk for visitors and employees. Adverse health effects related to trichloramine are skin and eye irritations, inflammations of the respiratory tract and asthma. Up to date, trichloramine in pool water has been measured only in few studies due to the lack of an appropriate analytical method. A fast, sensitive, easy applicable and low cost colorimetric method was developed and validated with membrane inlet mass spectrometry (MIMS). This allowed for the measurement of 30 samples from different pools which revealed that trichloramine concentrations are strongly correlated with free chlorine concentrations. Combined chlorine and pH are weakly correlated with trichloramine while urea showed no correlation with trichloramine. A field study confirmed that the trichloramine concentration responds quickly to changes of the free chlorine concentration. Furthermore, trichloramine concentration in a wading pool increased with the number of bathers. The most common technique to mitigate combined chloramines (inclusive trichloramine) is UV treatment. Laboratory experiments showed that the trichloramine quantum yield in purified water is 2.1 ± 0.1 mol einstein-1. Quantum yields in pool water were in a similar range and they were influenced by the free chlorine concentration. From laboratory experiments it can be concluded that standard UV reactors in Swiss swimming pools degrade 30-50% of the trichloramine per treatment cycle. This was confirmed by an on-site measurement. However, the effect of UV treatment on trichloramine concentrations in the pools (wading and swimming pool) was less pronounced (20% and 10% reduction, respectively) because of the long residence time of the water in the pools (Figure 1).

Figure 1: Effect of UV treatment on NCl3 concentration in a wading pool.

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O-A4-05-03

Formation and reactivity of (organic) bromamines and their relevance in oxidative water treatment

Michèle B. Heeb1, Urs von Gunten1,2

1School of Architecture, Civil and Environmental Engineering (ENAC), École Polytechnique Fédérale de Lausanne (EPFL), CH-1015, Lausanne, Switzerland

2 Eawag, Swiss Federal Institute of Aquatic Science and Technology, Ueberlandstrasse 133, CH-8600 Duebendorf, Switzerland


Oxidative water treatment such as chlorination or ozonation is widely applied for disinfection, removal of taste and odor compounds and the elimination of (anthropogenic) micropollutants. Bromide (Br-) has, besides natural organic matter (NOM), been identified as one of the key components of the water matrix relevant in oxidation processes. It is present in all freshwaters in concentrations ranging from a few mgL-1 to several mgL-1 and is non-toxic at these concen trations. During oxidative water treatment bromide can be oxidized to bromine (hypobromous acid, HOBr). Even though bromide concentrations in source waters and thus also HOBr concentrations are small compared to the primary oxidants, it can have a significant impact on the formation of disinfection by-products and transformation products as well as on the degradation of micropollutants [1]. This is due to its high reactivity, especially towards phenolic (apparent second-order rate constants in the order of 103 to 105 M-1s-1 at pH 7), amine and sulfamide moieties (apparent second-order rate constants in the order of 105 to 106 M-1s-1 at pH 7) but also with inorganic compounds such as ammonia, iodine, sulfite and cyanide (apparent second-order rate constants in the order of 103 to 109 M-1s-1 at pH 7) [1]. Only lim ited data is available on the kinetics of bromine with amines. These reactions lead to the formation of bromamines, which are considered to be reactive themselves. However, data on their reactivity is scarce as well. Our goal is thus on one hand to determine the kinetics of bromamine formation and on the other hand, to investigate their reactivity with components of the water matrix. Stopped-Flow measurements were performed to determine rate constants of the reaction of HOBr with methylamine, dimethylamine and N,N-dimethylsulfamide, while the reactivity of bromamines (inorganic bromamine, bromomethylamine, dibromomethyl amine, and bromodimethylamine) with phenol was assessed using DPD, a colorimetric assay, and HPLC analysis. Phenol was chosen as a surrogate for organic matter in the water matrix. Bromamines are formed rapidly with species-specific rate constants of around 108 M-1s-1 and apparent second-order rate constants in the order of 104 to 105 M-1s-1 at pH 7. Furthermore, the selected bromamines react with phenols with apparent second-order rate constants in the order of 102 M-1s-1 at pH 7, forming bromophenols with a yield of around 30 %. This data (which will be supplemented with further experiments) will allow for kinetic modeling of the various competing reactions during oxidative water treatment, i.e. the formation of HOBr in the first place, the reaction of the oxidant with the amine, the reaction of HOBr with the amine and the further reaction of the bromamine (but also of HOBr and the oxidant itself) with organic matter. This study is an important step towards a quantitative understanding of the fate of bromine during oxidative water treatment processes in presence of amine- and phenol-type moieties in terms of oxidation and by-product formation.

Reference: [1] Heeb, MB, Criquet, J, Zimmermann-Steffens, SG, von Gunten, U, Water Res. 48, 15-42 (2014).

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O-A4-05-04

Role of bromide for N-nitrosamine formation from nitrogen-containing precursors during ozonation

S.G. Zimmermann-Steffens1, U. von Gunten.1,2

1School of Architecture, Civil and Environmental Engineering (ENAC), Ecole Polytechnique Fédérale de Lausanne (EPFL), 1015 Lausanne, Switzerland

2 Eawag, Swiss Federal Institute of Aquatic Science and Technology, 8600 Dübendorf, SwitzerlandPresenting author: [email protected]

N-nitrosamines are a toxic class of nitrogenous disinfection by-products (N-DBPs) which can form during oxidative water treatment. Most research has focused on N-nitrosodimethylamine (NDMA) as prominent member of the class of N-nitrosamines. Bromide catalysis is an important NDMA formation mechanism from the precursor dimethylsulfamide (DMS) during ozonation [1]. The present study focuses on the role of bromide for the formation of N-nitros-amines from N-containing precursors during ozonation. The structure of the potential sulfamide- and hydrazine-type precursors was systematically varied. Reaction solutions were screened after ozonation by means of a HPLC - post-column UV photolysis/Griess reaction method that detects nitroso- and nitro-moieties adjacent to C- or N- atoms [2].N,N-methylethylsulfamide (MES) and N,N-diethylsulfamide (DES) could be confirmed to be precursors for the corresponding N-nitrosomethylethylamine (NMEA) and N-nitrosodiethyl-amine (NDEA), respectively. In analogy to DMS/NDMA [1], the formation pathway is bromide-catalyzed. In contrast, ozonation of the monosubstituted methylsulfamide did not lead to the corresponding N-nitrosomethylamine. This might be due to an additional site of HOBr attack at the monomethylated N-amine as compared to the dialkylated sulfamides DMS, MES, or DES. Substituting the primary N’-amine of DMS with one or two methyl groups prevented the formation of any N-nitrosamine since the methyl groups cannot be cleaved from the sulfamide structure by ozone or HOBr attack. In contrast, substitution with one phenyl group led to the formation of NDMA, a reaction which was bromide-catalyzed. Further sulfamide precursors tested contained a differently substituted phenyl ring at the N’-amine (tolylfluanide (TF) and five TF biometabolites). NDMA was the only N-nitrosamine forming, with bromide catalysis being confirmed for TF so far. It is hypothesized that the phenyl ring is the first site of oxidant attack, yielding DMS and subsequently enabling NDMA formation. Other precursors investigated contained a preformed N-N bond as building block for potential N-nitrosamines. Exclusive NDMA formation was confirmed for two hydrazines with the preformed dimethylamine group: unsymmetrical dimethylhydrazine and daminozide, for which bromide catalysis was excluded. Micropollutants containing a triazenyl or hydrazine moiety showed signals in the Griess method. However, the structure of these products still has to be elucidated by high resolution mass spectrometry.The results from the present study will further deepen our understanding of N-nitrosamine formation and potentially allow a mitigation of this toxic class of N-DBPs.

1. U. von Gunten, E. Salhi, C.K. Schmidt, W.A. Arnold, Environ. Sci. Technol. 44 (15), 5762 – 5768 (2010).

2. M. Lee, Y. Lee, F. Soltermann, U. von Gunten, Water Res., 47, 4893 – 4903 (2013).

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O-A5-01-02

COMPREHENSIVE TWO-DIMENSIONAL LIQUID CHROMATOGRAPHY APPLIED TO NATURAL ORGANIC MATTER FROM URBAN ATMOSPHER-

IC AEROSOLS

A.S. Paula, C.A.D. Loureiro, S.M.S.C. Freire, R.M.B.O. Duarte, and A.C.Duarte

Department of Chemistry & CESAM, University of Aveiro, 3810 - 193 Aveiro, PortugalPresenting Author: [email protected]

The interest of studying natural organic matter (NOM) in atmospheric aerosols has become an emer-gent topic in Atmospheric Chemistry. Indeed, its chemical composition, structural characteristics, and effects on climate and health are far from being known in detail. For the purpose of resolving the chem-ical heterogeneity of such complex organic mixtures, comprehensive two-dimensional liquid chroma-tography (LC×LC) was employed to map the hydrophobicity versus molecular weight (MW) distribu-tion of NOM from atmospheric aerosols collected during different seasons in an urban location at the Western European Coast (Aveiro, Portugal).

The LC×LC method employed a mixed-mode hydrophilic interaction column operating under aqueous reversed-phase mode in the first dimension, and a size-exclusion column in the second dimension. The LC×LC fractions were screened on-line by a photodiode array and fluorescence detectors. Findings suggest that the combination of two independent separation mechanisms is promising in extend the range of NOM separation. The applied LC×LC method also indicate that the aerosol NOM samples collected in different seasons exhibit dissimilar profiles in terms of average MW and hydrophobicity.

Acknowledgements:

Centre for Environmental and Marine Studies (PEsT-c/MAR/LA0017/2013, University of Aveiro, Portugal) and the Portu-guese Science and Technology Foundation (FCT), through the European Social Fund and “Programa Operacional Potencial Humano – POPH”, are acknowledged for financial support. This work was also funded by FEDER under the Operational Program for Competitiveness Factors – COMPETE and by National funds via FCT within the framework of research proj-ects ORGANOSOL (PTDC/CTE-ATM/118551/2010) and CN-linkAIR (PTDC/AAG-MAA/2584/2012).

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O-A5-01-03

UNFOLDING THE STRUCTURAL FEATURES OF ORGANIC AEROSOLS BY NMR SPECTROSCOPY

R.M.B.O. Duarte1, A.M.S. Silva2, A.C. Duarte1

1Department of Chemistry & CESAM, University of Aveiro, 3810-193 Aveiro, Portugal 2Department of Chemistry & QOPNA, University of Aveiro, 3810-193 Aveiro, Portugal


Organic aerosols (OA) encompass a multitude of molecular structures, physical properties, and sourc-es. This complexity constitutes a major obstacle to an improved understanding of OA chemistry and composition, but also on how OA affect the climate system, atmospheric processes, and human health. Unfolding the detailed composition and structure of such complex atmospheric organic mixtures is a truly exciting challenge that offers unparalleled rewards toward a better understanding of their role in various atmospheric processes. This study highlights the potential and limitations of nuclear magnetic resonance (NMR) spectroscopy to deliver new qualitative information on the substructures present in natural organic matter (NOM) from fine atmospheric aerosols collected at different locations during different seasons. The emphasis is given on the wealth of information that is obtainable with solid-state 13C NMR and one- and two-dimensional solution-state NMR methods and on how these data can be employed for assessing aerosol source fingerprints in different areas with disparate levels of pollution. By combining the information provided by all these NMR experiments, it was possible to identify a set of organic structures, which are likely to be representative of the whole NOM mass in the studied aerosol samples.

AcknowledgmentsCentre for Environmental and Marine Studies (PEsT-c/MAR/LA0017/2013, University of Aveiro, Por-tugal) and the Portuguese Science and Technology Foundation (FCT), through the European Social Fund and “Programa Operacional Potencial Humano – POPH”, are acknowledged for financial support. This work was also funded by FEDER under the Operational Program for Competitiveness Factors – COMPETE and by National funds via FCT within the framework of research projects ORGANOSOL (PTDC/CTE-ATM/118551/2010) and CN-linkAIR (PTDC/AAG-MAA/2584/2012).

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O-A5-01-04

CONTAMINATION OF SETTLED INDOOR DUST WITH POLYCYCLIC AROMATIC HYDROCARBONS IN THE UK: SOURCES AND

SIGNIFICANCE AS AN EXPOSURE PATHWAY

Y. Ma, S. Harrad

School of Geography, Earth & Environmental Sciences, University of Birmingham, Birmingham, United Kingdom, B15 2TT


Polycyclic aromatic hydrocarbons (PAH), a group of pollutants with reported adverse health impacts including cancer, are emitted inadvertently from a wide range of combustion activities (e.g. cooking, heating, vehicle exhausts, etc.) in indoor environments.1 While human exposure to these chemicals via the diet and inhalation of indoor air has been widely studied; very little is known about exposure via contact with indoor dust present on surfaces such as floors, soft furnishings and tables etc.2 Indeed to date, concentrations of PAH have been reported in only 1 sample of indoor dust from the UK.3 Thus, our study (by investigating more than 50 UK homes and collecting more than 200 samples) provides a valuable base-line evaluation of the range of exposure of the UK population to PAH received via ingestion of indoor dust. We will also examine potential putative sources of contamination with PAH in indoor dust. Our findings will both aid risk assessment, and by improving our understanding of the sources of such contamination, will inform strategies to reduce such contamination.

References1. K. Srogi, Environ. Chem. Lett. 5, 169–195, (2007).2. C. A. Menzie, B. B. Potocki, and J. Santodonato, Environ. Sci. Technol. 26, 1278–1284 (1992).3. N. Anders, M. Abb, E. Sorkau, R. Kubinec, and W. Lorenz, Fresen. Environ. Bull. 21, 372–379 (2012).

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O-A5-01-05

1H NMR STUDIES OF ALKALINE-SOLUBLE ORGANIC MATTER FROM URBAN ATMOSPHERIC AEROSOLS

S.P. Lopes1, C.A.D. Loureiro1, S.M.S.C. Freire1, R.M.B.O. Duarte1, A.M.S. Silva2, A.C. Duarte1

1Department of Chemistry & CESAM, University of Aveiro, 3810-193, Aveiro, Portugal2Department of Chemistry & QOPNA, University of Aveiro, 3810-193, Aveiro, Portugal


Over the last two decades, understanding the water-soluble organic matter in atmospheric particles has been the focus of the majority of environmental researchers, mostly because it represents the ma-jor fraction (~20-70%) of particulate matter in the atmosphere, and it could be involved in several atmospheric processes. Nowadays, an emerging topic has been the organic particulate matter that is water-insoluble, in particular the alkaline-soluble organic matter (ASOM), which could account for up to 14% of the organic aerosol carbon. Taking into account that this organic fraction still is poorly understood, a new extraction methodology was developed to isolate the ASOM from fine atmospheric aerosols collected over different seasons in an urban location - Aveiro, Portugal.

Solution-state proton nuclear magnetic resonance (1H NMR) was used for the first time to characterize the structural features of the ASOM extracted from fine atmospheric aerosols. Aliphatic structures are the dominant moieties, followed by oxygenated and unsaturated aliphatic groups, and only a minor contribution from aromatic groups. The most striking feature is that the ASOM samples from colder seasons show a higher aromatic content and a lower amount of aliphatic structures than samples from the warmer period. The winter samples also appear to have lignin-like compounds probably due to wood-burning processes for house heating in domestic fireplaces.

Acknowledgments: Central for Environmental and Marine Studies (PEsT-c/MAR/LA0017/2013, University of Aveiro, Por-tugal) and the Portuguese Science and Technology Foundation (FCT), through the European Social Fund and “Programa Op-eracional Potencial Humano – POPH”, are acknowledged for financial support. This work was also funded by FEDER under the Operational Program for Competitiveness Factors – COMPETE and by National funds via FCT within the framework of research projects ORGANOSOL (PTDC/CTE-ATM/118551/2010) and CN-linkAIR (PTDC/AAG-MAA/2584/2012).

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O-A5-01-06

FORMATION OF SECONDARY ORGANIC AEROSOL ON AQUATED HAZE-AEROSOL WATER: ISOPRENE OXIDATION AND POLYMERIZATION

Michael R. Hoffmann

Environmental Science & EngineeringLinde-Robinson Labs, California Institute of Technology

Pasadena, California 91125 [email protected]

The fate of isoprene (2-methyl-1,3-butadiene, ISO) emissions into the atmosphere is not fully understood. Increasing awareness that ISO is only partially processed in the gas-phase has refocused attention on its reactive uptake by fog, cloud, and aerosol droplets. A hydrophobic gas, ISO should preferentially partition to the surface rather than the bulk of aqueous aerosols such as haze, fogs, or clouds. These aquated aerosol phases are saturated with dissolved O2 and water-soluble unsaturated organics; they also support OH radical generation rates primarily from the solar photolysis of dissolved H2O2 that are several orders of magnitude larger than in the gas-phase. Similar results are obtained using TiO2 and Fe2O3 in suspension without the addition of added H2O2. ISO is converted therein to heavier products rather than into the C4 to C5 volatile compounds produced in the gas-phase. At λ >305 nm, photolysis of H2O2 in dilute aqueous ISO solutions yields C10H15OH species as primary products, whose formation both requires and is inhibited by O2. A minimum of seven C10H15OH isomers are resolved by reverse-phase high-performance liquid chromatography and detected as MH+ (m/z = 153) and MH+-8 (m/z = 135) signals by electrospray ionization mass spectrometry. Our findings are consistent with the addition of center OH radical to ISO, followed by HO-ISO radical reactions with ISO in competition with O2, leading to second generation HO(ISO)2 radicals that terminate as C10H15OH via beta-H abstraction by O2. We have shown that a significant fraction of gas-phase olefins should be converted into less volatile species via this process on wet airborne particles. In addition, to hydroxyl radical generated via hydrogen peroxide photolysis, Fenton’s reaction involving H2O2 and Fe(II)/Fe(IV) species also take place. In these reactions interfacial Fe(II) ions react with H2O2 and O3 > 103 times faster than Fe(H2O)6

2+ in bulk water via a process that favors inner-sphere two-electron O-atom transfer over outer-sphere one-electron transfers. The higher reactivity of di-iron ferryl ions vs. O=Fe(IV) as O-atom donors indicates that electronic coupling of mixed-valence iron centers in the weakening of the Fe(IV)-O bond in polymeric-iron ferryl species.

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O-A5-02-02

AIR-SEA EXCHANGE OF PAHs, PCBs, OCPs AND PBDEs IN THE AEGEAN 2012

G. Lammel1,2, C. Samara3, D. Voutsa3, B. Vrana1, A. Besis3, C. Efstathiou1, F. X. Meixner2, P. Přibylová1, R. Prokeš1, T. Rusina1, G. Z. Song2

1 Masaryk University, Research Centre for Toxic Compounds in the Environment, 62500 Brno, Czech Republic

2 Max Planck Institute for Chemistry, 55128 Mainz, Germany3Aristoteles University, Dept. of Chemistry, 54124 Thessaloniki, Greece


Seawater is storing persistent organic substances following atmospheric transport from land-based sources and deposition as well as riverine input. Following accumulation the direction of mass flux may reverse (net-volatilisation) turning the sea surface into a secondary source of pollutants (e.g. [1]).Organic trace substances in air were collected by passive (PAS, polyurethane foam disk deployed in protective chamber [2]) and active (high, medium and low volume) sampling (AAS) at sites in the Thessaloniki area / Thermaikos Gulf (5 locations) and at a remote site on Crete (2 locations) in July 2012. The effective sampling volume of PAS was ‘calibrated’ based on side-by-side PAS and high volume AAS (1 location). Silicone rubber (SR) sheets were applied as passive samplers of free dissolved contaminants in seawater [3]. From these measurements the direction of diffusive air sea exchange was determined (3 locations). Based on AAS from 2 heights above ground and measurement of the turbulent exchange coefficient by an Eddy covariance system [4] the vertical flux of several PAHs and OCPs could be determined (1 location). Vertical gradients were derived for sampling intervals with replica concentrations determined [5]. Chemical analysis of 28 3-6-ring PAHs, 13 OCPs, 7 indicator PCBs and 8 PBDEs was by organic solvent extraction from sampling media, followed by extract fractionation and instrumental analysis by GC-MS. All results were corrected for field blanks. Surrogate recovery standards were spiked prior to extraction.The results are discussed in the context of local processes (air-sea exchange), sources and long-range transport of the pollutants in and to the Aegean.

References1. I. Stemmler and G. Lammel G, 2009, Geophys. Res. Lett. 36, L24602 (2009).2. J. Klánová, P. Cupr, J. Kohoutek and T. Harner, Environ. Sci. Technol. 42, 550-555 (2008).3. T. Rusina, F. Smedes, M. Kobližková and J. Klánová, Environ. Sci. Technol. 44, 362-367 (2010).4. V. Wolff, I. Trebs, C. Ammann and F.X. Meixner, Atmos. Meas. Techn. 3, 187-208 (2010).5. G. Lammel, J. Klánová, L. Erić, P. Ilić, J. Kohoutek and I. Kovacić, J. Environ. Monit. 13, 3358 –

3364 (2011).

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O-A5-02-03

The Impact of Aerosols on Global Horizontal Irradiance over Southeastern Anatolia of Turkey

Burak Öztaner1, Ceyhan Kahya2, Selahattin Incecik2

1Istanbul Technical University, Eurasia Institute of Earth Science, Climate and Marine Science, Maslak Istanbul Turkey

2Istanbul Technical University, Department of Meteorology, Maslak Istanbul Turkey

ABSTRACT

The present study deals with the impact of aerosols on global horizontal irradiation which are assessed during the periods April 2011 and April 2012 over Southeastern Anatolia in Turkey using ground-based measurements, WRF model and satellite data. Aerosols affect the earth’s atmosphere through interactions with solar and terrestrial radiation as well as clouds. Solar energy utilization in various applications has increased seriously considered for satisfying a significant part of the energy demand in Turkey due to its geographical position. Specifically Southeastern Anatolia (SEA) of Turkey present a significant potential of solar energy. A photovoltaic power production is significantly dependent on Global Horizontal Irradiance (GHI), cloudiness and aerosols.

The aim of the study is to understand the impact of aerosols on GHI over the SEA region. For this purpose daily MODIS Level-2 aerosol optical depth (AOD) data obtained from MODIS Terra platform products are used. MODIS at 550 nm have a spatial resolution of 500m.

In addition to AOD data, PM10 data measured at ground level air quality stations in SEA, is used for the air quality stations of SEA (Kilis, Bozova, Mardin and Sırnak). The relationship of AOD and GHI are examined for spring (MAM) and summer (JJA) seasons. The time series of GHI data with AOD for spring and summer of 2011 and 2012 are compared. We found a significant negative relationship between AOD and GHI data for all sites (Level of significance is less than 0.001). Similarly, AOD and PM10 data are compared for both seasons. The scatter plots reveal that there exists a relationship between PM10 and AOD 550 nm in both season. The mean AOD levels in summer are higher than in the spring season. Furthermore, the Cloud-Aerosol Lidar and Infrared Pathfinder Satellite Observations (CALIPSO) data is used to provide continuous high resolution vertical profiles of aerosol properties. Finally, back trajectories have been used to infer source regions of the investigated region via an integrated WRF/HYSPLIT modeling approach. The model is run for the selected episode periods (exceeding air quality standard level) 14-21 April 2011 and 6 -12 April 2012. Modeling results show that aerosols, which have effect on GHI, transport from Saharan, Egyptian and Syrian deserts.

The results show that the satellite measurements are able to measure and observe the increase of the dust concentrations over the SAE region of Turkey.

Keywords: Aerosol, AOD, dust transport, global horizontal irradiance, CALIPSO

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O-A5-02-04

PAH in PM10 collected in São Paulo, Brazil (2003-2013)

P. Vasconcellos1, S. E. Caumo1, G. Pereira1, S. Soares1, J. B. De Andrade2

1 Institute of Chemistry, University of São Paulo, São Paulo, BrazilPresenting author email: [email protected]

Aerosols were collected from 2003 to 2013 at an urban site in São Paulo city, Brazil (n=152 samples). Samples were collected during the winter and during 3 extensive campaigns (spring, summer and autumn) in the campus of the University. This site is a green area, ~ 2 km from the road with intense traffic of heavy and light vehicles, and with influence of long-range transport of pollutants. Organic compounds were extracted in Soxhlet apparatus with dichloromethane and the different fractions were obtained with a silica gel column and different solvents of increasing polarity following the procedure proposed by Gogou et al. (1998).

The results show that in the wintertime total PAH average concentrations were circa of 7 times higher than in the other seasons. In the wintertime, the lighter PAH presented the higher concentrations than the heavier PAH and fluoranthene and pyrene were the most abundant compounds. On the other hand, chrysene and Benzo(ghi)perilene were more abundant in the samples collected in warmer seasons. Ratios between some PAH showed that in situ emissions are predominant, and the presence of retene in the winter samples indicate the mass transport from sugarcane region contributes to air pollution (Vasconcellos et al., 2010).

Figure 1: PAH concentrations collected during winter (intensive) and extensive campaigns.

Benzo(a)pyrene equivalent values show higher risk of cancer in samples collected during the winter campaigns than in extensive campaigns.

References1. Gogou, A., Apostolaki, M. et al., J. Chrom. 799, 215 (1998).2. P. Vasconcellos, Souza, D. et al., 408, 5836 (2005).

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O-A5-02-05

SOURCE APPORTIONMENT OF ORGANIC AEROSOL IN AMAZON REGION

P.C. Vasconcellos1, N. de Oliveira Alves2, J. Brito3, A. Arana4, S. E. Caumo1, P. Artaxo3, S. Hacon5, R. Hillamo6, S. R. Batistuzzo de Medeiros7

1 Institute of Chemistry, University of São Paulo, São Paulo, Brazil2 Biochemistry Department, Federal University of Rio Grande do Norte, Natal, Brazil

3 Institute of Physics, University of São Paulo, São Paulo, Brazil4 National Institute for Amazonia Research, Manaus, Brazil

5National School of Public Health at Oswaldo Cruz Foundation, Rio de Janeiro, Brazil6Finnish Meteorological Institute, Atmospheric Composition Research, Helsinki, Finland

7 Cellular Biology and Genetics Department, Federal University of Rio Grande do Norte, Natal, BrazilPresenting author email: [email protected]

The Brazilian Amazon contains about 40% of the world’s remaining tropical rainforest, corresponding to 61% of the area of Brazil [1]. The appropriate source identification is fundamental as guidance of public health policies and providing foundations for health intervention.

The aim this work is to evaluate the origin of organic compounds using a Principal Component Analysis (PCA) near Porto Velho, southwest of Brazilian Amazon region.

The results show a three-factor solution was resolved by PCA analysis (Table 1).

Table 1: Results of PCA analysis.

The results show a three-factor solution was resolved by PCA analysis. The first factor clearly showed that the source apportionment of OC (76%), EC (72%), levoglucosan (100%), and retene (100%) were dominated by biomass burning. The second factor depicts an important contribution of several PAHs without a single source class and therefore was considered as mixed sources factor. The third factor was characterized by more than 65% of each of dibenz[a,h]anthracene, indene[1,2,3-c,d]pyrene and benz[g,h,i]pyrene. Also, about 20% of OC and EC were associated with this factor. Therefore, this factor was considered as diesel emissions that are higher during the dry season because there is a great demand for energy supply. This is also a critical period for the human health implications.

This work enhances the knowledge of aerosol sources on an Amazon region highly impacted by anthropogenic activities with significant contribution on climate and potential risks to human health, especially for the most vulnerable groups.

AcknowledgementsThis work was supported by CNPq and Brazilian National Institute of Science and Technology (INCT) for

Climate Change funded by CNPq Grant Number 573797/2008-0 and FAPESP Grant Number 2008/57719-9.

Reference[1] Davidson, E. a, De Araújo, A. C., Artaxo, P. et al. (2012). The Amazon basin in transition. Nature, 481(7381).

CompoundsBiomass Burning Mix Diesel

F1 F2 F3Levoglucosan 0.93 0.23 0.12

Organic carbon 0.92 0.14 0.11Retene 0.87 0.23 0.04PM10 0.86 0.14 0.21

Elementar Carbon 0.85 0.27 0.33Benz[e]Pyrene 0.76 0.54 0.22

Anthracene 0.23 0.89 0.25Chrysene 0.29 0.82 0.49Pyrene 0.33 0.77 0.53

Benz[a]anthracene 0.31 0.75 0.57Benz[a]pyrene 0.40 0.71 0.57

Benz[b]fluoranthene 0.42 0.67 0.60Benz[g,h,i]pyrene 0.20 0.30 0.93

Dibenz[a,h]anthracene 0.21 0.30 0.93Indene[1,2,3-c,d]

pyrene 0.12 0.41 0.89Benz[k]fluoranthene 0.33 0.62 0.69

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O-A5-02-06

MULTI-ELEMENTS ATMOSPHERIC DEPOSITION STUDY IN ALBANIA

P. Lazo1, F. Qarri2, L. Bekteshi3, T. Stafilov4, M. Frontasyeva5, H. Harmens6

1 Department of Chemistry, Faculty of Natural Sciences, University of Tirana, 10, Tirana, Albania

2 Department of Chemistry, University of Vlora, 13, Vlora, Albania3 Department of Chemistry, Faculty of Natural Sciences, University of Elbasan, 23,

Elbasan, Albania4 Institute of Chemistry, Faculty of Science, Sts. Cyril and Methodius University, 1000,

Skopje, Macedonia5 Frank Laboratory of Neutron Physics, Joint Institute for Nuclear Research, 141980, Dubna, Russia

6 Centre for Ecology & Hydrology, BT20, Bangor, United Kingdom Presenting author: [email protected]

Air quality can be monitored by measuring the concentration of pollutants in the air or directly on deposits by building models that describe the transport of pollutants or by using biomonitors [1]. Through the use of different types of vegetation, the levels of atmospheric trace metal deposition have been successfully monitored [2]. The use of native terrestrial ectohydric mosses as biomonitors is now a well-recognized technique in studies of atmospheric contamination [3] and is applied as a practical mode in establishing and characterizing deposition sources.For the first time, the moss biomonitoring technique and ICP-AES analysis were applied to study the multi-element atmospheric deposition in Albania. Moss samples (Hypnum cupressiforme) were collected during the summer of 2011 and autumn 2010 from 44 sites, evenly distributed over the country. The sampling was performed in accordance with the LRTAP Convention–ICP Vegetation protocol and the strategy of the European Programme on Biomonitoring of Heavy Metal Atmospheric Deposition. This study was conducted in the framework of ICP Vegetation in order to provide a reliable assessment of air quality throughout Albania and to produce information needed for better identification of contamination sources and improving the potential for assessing environmental and health risks in Albania, associated with toxic metals. The spatial distribution of 19 elements throughout the Albanian territory was explored in this research. For comparison, the Albanian data were compared with neighboring countries [3] and with Norwegian moss data from a pristine area [4]. For better interpretation of the results, the contamination factor (CF) scales [5] were used to interpret the results of CFs values obtained in this study and to distinguish the contamination level caused by each element. Cluster and factor analysis with varimax rotation were applied to distinguish elements mainly of anthropogenic origin from those originating from natural sources. The geographical distribution maps of the elements over the sampled territory were constructed using GIS technology. The median values of the elements in moss samples of Albania were high for Al, Cr, Ni, Fe, and V and mediate for Cd, Cu, and Pb compared to other European countries, but generally were of a similar level as some of the neighboring countries such as Bulgaria, Croatia, Kosovo, Macedonia, and Romania.

References1 B. Markert, A.M. Breure, H.G. Zechmeister (2003) Bioindicators and biomonitors. Elsevier, Oxford, pp 3–392 J. Schilling, M. Lehman (2002) Atmospheric Environment 36:1611–16183 Harmens H, Norris D, Mills G. and the participants of the moss survey, (2013), Heavy metals and nitrogen in mosses: spatial patterns in 2010/2011 and long-termtemporal trends in Europe, 63 p. http://icpvegetation.ceh.ac.uk 4 E. Steinnes, T. Berg, H.Uggerud, M. Vadset (2007) State Program for Pollution Monitoring, Report 980/2007, Norwegian State Pollution Control Authority, Oslo 2007, 36 pp. (In Norwegian)5 J.A. Fernandez and A. Carballeira (2001). Arch Environ Contam Toxicol 40:461–468. doi:10.1007/s002440010198

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O-A5-03-01

POLLUTION CHARACTERIZATION OF ORGANIC ATMOSPHERIC EMISSION IN THE ARCTIC BY COMBINING QUANTITATIVE TRACE

ANALYSIS WITH SCANNING ELECTRON MICROSCOPY

K. Schütze3, R. Kallenborn1,2, S. Weinbruch3

1Institute for Chemistry, Biotechnology and Food Sciences, Norwegian University of Life Sciences (NMBU), NO-1432 Ås, Norway.

2University Centre in Svalbard (UNIS), Department of Arctic Technology, NO-9171 Longyearbyen, Svalbard, Norway

3Institute for Applied Geosciences, Technical University of Darmstadt, DE-64287 Germany

During two subsequent sampling campaigns in 2011 and 2012, simultaneous sampling for aerosol char-acterization and the polycyclic aromatic hydrocarbons (PAH) and polychlorinated biphenyls (PCB) quantification was conducted in the vicinities of the power plants and from Arctic background samples in Longyearbyen and Barentsburg (Svalbard; Norwegian Arctic). The particle/ aerosol characterization was performed using Environmental Scanning Electron microscope (ESEM) at the Technical Uni-versity Darmstadt (Germany). The trace analytical quantification of the air samples was done at the analytical laboratories of the Norwegian University of Life Sciences (UMB), Dept. of Chemistry, Bio-technology and Food Sciences (IKBM) using gas chromatography coupled to a low-resolution mass spectrometer in Electron impact mode. During the 2012 campaign (01. – 14.03.2012), air samples were taken at 7 different locations in Barentsburg and Longyearbyen in distinct differences from the local electric power plants identified as significant local contamination source for the emission of organic pollutation to the nearby settlements. The highest levels for PAHs were found for the direct gas phase emissions from the Longyearbyen power plant (74 mg/m3 total PAH, around 90% of the emissions via the gas phase). The major contributions in the direct emitted air samples are associated with Benzo[a]pyrene and Benzo[a]flouranthene. The distribution of PAH in the background stations is mainly influ-enced by a combination of direct local emissions and PAHs reemitted from secondary sources. The particle composition and characterization of the emitted aerosols were performed by environmental scanning electron microscope (ESEM). Particle distribution as well as mineral composition testing was done and combined with the PAH concentration data. The results of the here presented study confirm that PAH level distribution is obviously directly associated with the particle fractions identified in the emission samples.

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O-A5-03-02

POLYCHLORINATED BIPHENYLS IN URBAN ATMOSPHERIC PARTICLES OF THESSALONIKI, GREECE

A. Tsolakidou, D. Voutsa, C. Samara

Environmental Pollution Laboratory, Department of Chemistry,Aristotle University of Thessaloniki, 54 124 Thessaloniki, Greece

Polychlorinated biphenyls are environmental contaminants regulated by the Stockholm Convention of Persistent Organic Pollutants due to their persistence, potential to bioaccumulate and toxicity. PCBs are among the organic pollutants usually found in airborne particles and contribute to their toxicity [1, 2, ].

In this study size segregated samples (<0.49μm, 0.49-0.97μm, 0.97-1.5μm, 1.5-3.0μm, 3.0-7.2μm and <7.2μm) of airborne particles were collected at an urban traffic and an urban background site in Thessaloniki, Northern Greece. Sampling was conducted during winter and summertime. Microwave assisted extraction with a 3:2 dichloromethane/hexane solution was employed for the extraction of the PCBs. The extracts were further cleaned up and fractionated on a silica gel/alumina column. The final extracts containing PCBs were analysed by employing GC-MS. Fifteen congenerss were determined: six dioxin-like polychlorinated biphenyls (PCB77, PCB105, PCB118 PCB126, PCB156 and PCB169), the Dutch-seven congeners (PCB28, PCB52, PCB101, PCB118, PCB138, PCB153, PCB180) together with PCB31, PCB128 and PCB170.

This study presents the particle size distribution of PCBs and their occurrence in the alveolar fraction. Spatial and temporal variations are discussed.

References

1. Breivik K., Sweetman A., Pacyna JM, Jones KC (2002) Sci Total Environ 290:181-198

2. Heal MR, Kumar P, Harrison RM (2012). Chem Soc Rev 41:6606–6630

3. Landlová L., Čupr P., Franců J., Klánová J., G. Lammel (2014) Environ Sci Pollut Res (DOI10.1007/s11356-014-2571-y)

AcknowledgementsThis research has been co-financed by the European Union (European Social Fund – ESF) and Greek national funds through the Operational Program “Education and Lifelong Learning” of the National Strategic Reference Framework (NSRF) - Research Funding Program: Thales. Investing in knowledge society through the European Social Fund. Project code/Title: MIS 377304/”Bioactivity of airborne particulates in relation with their size, morphology and chemical composition”.

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O-A5-03-03

X-Ray Diffraction Study of Asbestos Fibers in Urban Atmosphere of City of Pilsen (West Bohemia, Czech Republic)

D. Havlíček1, O. Vik1,3, M. Klán2, J. Plocek.3

1Dept. of Inorg. Chem., Faculty of Science, Charles University in Prague, 128 40, Praha 2 , Czech Republic

2Institute for Environmental Studies, Faculty of Science, Charles University in Prague, 128 40, Praha , Czech Republic

3Inst. of Inorg. Chem. of the ASCR, v.v.i., 250 68 Řež u Prahy, Czech Republic,Presenting author: [email protected]

Our work deals with actinolite occurrence in solid fraction of ambient aerosol in Pilsen basin, and its source apportionment. Such type of study can be successfully done when solving four basic problems: 1) sample collection, 2) measurement 3) way of evaluation and calculation, 4) deduction of the results. Ad 1: Our technology consists of collection dust particles on glass fibre (non-diffracting) filters in different places around the city and at different meteorological conditions. Ad 2: The filters were worked up directly by X-ray powder diffraction using parallel-beam geometry (like thin layer) and by electron microscopy. Ad 3: Semiquantitative analysis were done by “Reference Intensity Ratio” (RIR) method [1], used previously i.e. for XRD analysis of atmospheric dust in several other places [2], [3]. Ad 4: The origin of dust and source apportionment was studied with use of direct mineralogical analysis of potential dust sources (transport – engines, tyres, brakes, local burning places, heat plants ashes, building industry, quarries etc.) by X-ray diffraction. The minerals significant for each source were identified and searched on filters collecting atmospheric dust. Great surprise was high content of actinolite in some samples. We have clarified the origin of this mineral in atmospheric dust and identified its resources.

References1. B.L. Davis, Reference Intensity Method of Quantitative X-Ray Diffraction Analysis (Davis Consulting, Rapid City, 1988)2. B. L. Davis, Atmospheric Environment 18, 2197 (1984).3. B. L. Davis and Jixiang Guo, Atmospheric Environment 34, 2703 (2000).

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O-A5-03-04

Investigation of the partitioning behavior of Volatile Organic Compounds between air and airborne dust by means of Selected Ion Flow Tube Mass Spectrometry

Christophe Walgraeve, Kristof Demeestere, Jo Dewulf, Herman Van Langenhove

Research group EnVOC, Department of Sustainable Organic Chemistry and Technology, Ghent, Belgium

The investigation of the complex fate and behavior of pollutants in the environment is of paramount importance. In this respect, our research focuses on the study of the partitioning behavior of a selected set of volatile organic compounds (VOCs) between the free air phase and the airborne particulate matter. In order to quantify the partitioning coefficients of the VOCs, a state-of-the art analytical technique is used, namely Selected Ion Flow Tube Mass Spectrometry or SIFT-MS. The SIFT-MS is a new analytical technique for the real-time measurement of trace-gases and Volatile Organic Compounds (VOCs) concentrations. Detection limits in the lower ppbv level are obtained. By this technology, target molecules are ionized by chemical ionization using H3O

+, NO+ and O2+ precursor ions, produced by a

microwave discharge source. Product ions are formed and unreacted precursor ions are analyzed by a downstream quadrupole mass filter and allow for a direct calculation of the concentration of the VOCs. It is proven by our results that the SIFT-MS real-time measurement offers unique and new opportunities to study the interaction of VOCs with particulate matter. The partitioning coefficients for a selected set of volatile organic compounds (having different physical chemical properties) are determined. This was accomplished by the measurement of breakthrough curves of the VOCs through a column packed with airborne particulate matter. A step function of the target VOCs was applied to a column and the response was registered by means of SIFT-MS. Data obtained will be quantitatively discussed and the relevance of these determined partitioning coefficients with respect to odor nuisance caused by agricultural activities will be explained.

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O-A5-03-05

Assessment of volatile organic compounds exposure among different transporta-tion modes in Ghent, Belgium

Duc Hoai, Do; Herman, Van Langenhove; Stephen Izuchukwu, Chigbo; Abebech Nuguse, Amare; Kristof, Demeestere and Christophe, Walgraeve

Research group EnVOC (Environmental Organic Chemistry and Technology), Department of Sustain-able Organic Chemistry and Technology, Ghent University, Belgium

Abstract:

People spend up to 85-90% of their time indoors (houses, offices, bars), and a significant amount of time (5%) in traffic while commuting to and from work. Real life exposure to volatile organic com-pounds (VOCs) could be higher than estimated from concentration data obtained from fixed air quality stations. Increasing efforts of the government to promote public transportation (bus tram, metro, train) and healthy non-motorized alternatives (walking, cycling) as substitutes for cars makes it valuable to assess the exposure levels to which commuters, using different transportation modes, are exposed. Therefore, three transportation modes including tram, car and bicycle are selected and concentration levels of 84 volatile organic compounds were measured along a route in Ghent, Belgium. Concentra-tion levels were obtained by active sampling on Tenax TA sorbent tubes followed by thermal desorp-tion gas chromatography mass spectrometry (TD-GC-MS). It is observed that aromatic hydrocarbons account for a significant proportion in the total VOCs concentration (TVOCs) being as high as 41-57%, 59-72% and 58-72% for the tram, car and bicycle respectively. Commuters using the tram experience the highest TVOCs concentration levels. However, the physical activity level involving the mode of transportation is important to assess the exposure to toxic VOCs. It is proven that the commuter using a bicycle (4.3 ±1.5 µg) inhales seven and nine times more benzene compared to the commuter using the car and tram respectively, when the same route is followed.

Key words: VOC, active sampling, commuter exposure, inhalation dose, traffic air, transportation modes, tram, car, bicycle, Ghent, Belgium

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O-B1-01-03

PORTABLE NON INVASIVE ANALYSES FOR CULTURAL HERITAGE

S. Ridolfi1, E. Caponetti2, D. Chillura Martino3, M. L. Saladino3

1Arsmensurae, 00188, Rome, Italy2 Università di Palermo CGA, 90128, Palermo, Italy

3Università di Palermo STEBICEF, 90128, Palermo, ItalyPresenting author: [email protected]

Cultural Heritage needs to be preserved, conserved, and restored from time to time. Before or during the restoration process usually it is analyzed. It is in fact useful to know its nature and composition, not only for a conscious restoration, but also for identifying fakes or ancient restoration areas or simply to study the story of art.The requirements that the scientific analyses for Cultural Heritage must have are: nondestructive and noninvasive, multielemental, sensitive, reliable and sufficiently rapid, able to carry out measurements in situ on objects of all types, and to deduce information practically on-line. Among the techniques that fulfill these requirements we find: multispectral imaging, portable EDXRF, Raman and UV-VIS-NIR spectrometry [1]. But simply applying the techniques one after the other does not make a good job. To enhance the single results it is necessary to relate the results of each technique to the preceding ones and to the subsequent ones in order to produce an organic set of self explanatory data. In this paper we are going to show some cases in which it will appear clear the necessity of the correct order with which applying the non invasive techniques and what data of each of them it is necessary do understand in situ to obtain the maximum of the subsequent scientific techniques.In Figure 1 we see the application of multispectral imaging techniques on a painting on canvas to detect repainting and the application of XRF spectrometry to determine the pigments of the retouches.

Figure 1: Application of multispectral imaging and XRF spectroscopy on a painting on canvas

References1. R.Cesareo, S.Ridolfi. “Portable systems for EDXRF Analysis of Works of Art”, in “Portable X-ray

Fluorescence Spectrometry”, The Royal Society of Chemistry, ISBN 978-0-85404-552-5 (2008).

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O-B1-02-03

Chemists in Guatemala: The case of practicing as a Chemist were we are not needed

Fayver Manuel De León, Roy Morales

San Carlos University of Guatemala

In Guatemala, the formation of a Chemist requires a final step: Supervised practices in the Industry. Being an almost-Bachelor, there is a broad scope of possibilities were a chemist can develop knowledge in a variety of fields, as synthetic, analytic or theoretical chemist. But, the industries en Guatemala doesn’t have the need for knowledge: they only need someone that can perform only a couple of analyses, leaving the chemist thinking about the 5 years almost wasted in University. The same is with investigations. Because government guidelines for Science are almost none, investigations carried on are not focused on a path that a chemist can follow. The focus of the career is not on Industry, but in Science. For that, we propose two new focuses, because the actual one doesn’t fulfill the needs of industry and also, science in Guatemala.

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O-B2-01-02

Improving the efficiency of outstripping training of engineers in interaction with European Higher Education Area conditions.

N.Y. Bashkirtseva, M.V. Zhuravleva, O.V.Zinnurova, Vagapov B.R.

Kazan National Research Technological University, Russia

The construction of national innovation economy integrated into the global community determines the vector of development of innovative industries with breakthrough value.

Petrochemical complex is the most promising [1] revenue generating sector of the economy Russia. Trends in the development of oil and gas complex determine the focus of outstripping professional training, including fundamentalization with elements of versatility, complexity, variability, international focus, time optimization of the training on the basis of the cluster approach in the organization of the educational process.

One of the most promising forms of organization of innovative educational process of preparing engineers for petrochemical complex stands project-activity training.

The basic idea of the project-activity education is a graduate who has mastered the knowledge and ways of activity. In this case a student turns from passive consumer of knowledge to active subject of educational activities. Because in its future career a specialist will always face, adapt, participate and implement various types of innovations and focus on the individual work with independent decision making.

The project-active education is aimed at the following objectives: to form a specialist as a member of society; training of highly qualified personnel; continuing professional readiness, motivation for self-development and progress on the career ladder.

The essence of project-activity education of future engineers for the petrochemical complex is to train engineers required for enterprises to solve specific problems. A high level of professional training helps to enter the production activity in the enterprise without the adaptation period.

Designing project-active training of engineers for petrochemical plants was based on such principles as systematic, continuity, integration, interdisciplinary connections, correspondence and regionality.The mechanism for implementing the project-activity training of engineers includes several parts:

1) Forming project teams from students in association with companies;2) Development of individual training plans;3) Educational planning of the project-activity training considering a workload of students in the basic educational program;4) Development of institutional mechanisms of interaction between the university and the enterprises to implement the project-activity

training;5) Matching the content of training with companies:a) identifying subjects and organization forms of scientific research and development work carried out by students;b) content definition and control of all types of industrial practice by representatives of enterprises;c) attracting leading engineering personnel in the educational process;d) formation criteria of quality of professional training of engineers.6) Employment of graduates.

The educational process is built based on the level of education and training of students from course to course. It’s a dynamic system opened for change, transformation and continuous interaction of structural components with each other. Patterns and trends in the development of enterprises were taken into account when planning the content of the project-activity training of engineers. Changes in the technical and social progress, new technologies, production impact on the content and structure of professional activity. Therefore, the leading rule in determining the selection of the content of the project-activity training of engineers is to focus on current and foreseeable needs of the individual, businesses, industry, region and society in general [2].

Forms of Project and activity-oriented training: 1.Training of engineers on individual curricula, taking into account the specifics of production. Such specialists are needed

for enterprises to solve specific production problems. The University has contracts to carry out such training with the largest Russian enterprises.

2. Training of engineers in industrial branches of departments includes theoretical and practical training , так и практическое обучение under the direction of supervisors from the enterprises. Such system of education is used for the training:

- Engineers at oil and gas processing in design institute of the JSC «Lukoil»- Chemical technologists for basic organic and petrochemical synthesis in the production association “Kazanorgsintez”.3. Training of designers – specialists in the 3D design. Their training takes place at magistracy based on a leading design

organizations. Total number of students enrolled in the project magistracy is 180 people.4. Training of engineers-managers. It determined the relevance of opening management magistracy, which is preparing the

programs:Chemical engineering of petrochemical plantsLifecycle management of petrochemical companyQuality management in the production and technological systems.5. The task of strengthening the competitiveness of graduates in the labor market organization provided by additional education

for senior students:- Additional economic education of bachelors for “Economics and Management” program;

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-Additional qualifications: craftsman, operator of technological installations, laboratory analyst. The effectiveness of the implementation of innovative educational process is determined by the creation of conditions such as

the integration of education, science and industry, developing of the content of the training, the organization of the educational process, psychological and educational readiness of students, teacher’s competence, availability of appropriate material and technical base in vocational education and etc.

Improving the performance of outstripping training ensures the process of internationalization of education. Its beneficial effect is obvious: it is increasing the number of participants in the educational process by bringing relevant subjects of the international community and pooling their resources to improve the innovativeness of the organization, content and material-technical base of educational process; universalization of knowledge; expansion and strengthening of international cooperation with universities in a single line, scientific and professional societies and industries, that deepens the knowledge base of institutions and participants in the educational process and expands the scope of scientific researches, enriches the educational programs.

An example of a positive impact on the process of outstripping professional training for the oil and gas complex is the result of international cooperation of the federal state educational institution of higher professional education “Kazan National Research Technological University” and “European Chemistry Thematic Network Association” (ECTNA) which allows enriching of the educational process by the strengths that the integrable subject has.

The activities of ECTNA focuses on four areas: creating conditions for a quality education, organization and development of distance education, intensification of training and increasing the attractiveness of chemical education in the community. To do this following tools are used:• a virtual community on Chemical Education, which provides vocational and higher education institutions students, , as well as scientists and engineers, the opportunity to cooperate;• European quality marks in chemistry: Eurobachelor, Euromaster and Chemistry Doctorate Eurolabel, which is awarded for the development and implementation of basic education programs in chemistry or interdisciplinary programs, As well as for research in chemistry and related sciences;• intensive scientific school on chemistry for researchers, teachers and students, which are the means of transfer of modern specialized knowledge and skills, enhance multinational cooperation and intercultural communication at the undergraduate and teaching level, the development of specific to the subject area language skills.

The implementation of these mechanisms in the educational process will ensure: increasing the motivation of students to higher levels of competence; institutional partnerships; the creation of strategic educational alliances; mobility of educational programs and institutional mobility; increased academic and professional mobility of students, teachers and professionals; integration into the curriculum and the international dimension of educational standards; the formation of a team of engineers-professionals with international certifications to employers.

Internationalization as an objective process of sustainable interaction and mutual influence of national systems of higher education contributes to the development of international integration of universities. This allows you as a promising areas of international cooperation, to improve the quality of outstripping training to consider:

development of individual mobility of the teaching staff, students, graduates; the formation of an integrated system of foreign training of scientists and teachers; realization of joint international scientific researches; the creation of strategic educational alliances; integration into the global programs of the European educational space; the establishment of international educational programs with the issuance of double diplomas; marketing and promotion of research projects and educational programs.

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O-B2-03-02

EDUCATION IN GREEN AND SUSTAINABLE CHEMISTRY IN SPAIN AT THE POSTGRADUATE LEVEL

B. Altava, M. I. Burguete, E. García-Verdugo, S.V. Luis.

Dept. of Inorganic and Organic Chemistry, University Jaume I, E-1208, Castellón, SpainPresenting author: [email protected]

During the last decade, researchers and University teachers from different Spanish Institutions have cooperated in the effort of developing an integrated and cooperative program for Master and PhD interuniversity studies in Sustainable Chemistry (www.miqs.uji.es). This process was integrated in the context of the generation of the European Higher Education Area (EHEA), which has led, in Spain, to a large number of continuous legal modifications. The selection of the subjects to be included in Master was based on the definition of several modules that were then developed in different courses that could be modified and adapted easily when required. The inclusion of a module related with general training in basic concepts in chemistry, engineering and technology allowed for a simple homogenization, when required, of students coming from different backgrounds. Our common program has been able to survive with a high level of vitality during last years, having trained several hundreds of postgraduate students. It is important to note that more than 30% of the students proceeded from foreign countries: America, Europe and North Africa.

The Master degree represents the central learning activity for the students in terms of courses to be followed. Those activities are to be completed by an experimental work properly defined in areas related to Sustainable Chemistry. In the case of the PhD studies, the research is the main activity and requires having followed the Master courses or, at least to demonstrated a sound training in the corresponding subjects. This research, is however to be completed with complementary teaching activities based on a system of common workshops and seminars to be carried out on a yearly bases. Thus, the overall system involves a high level of exchange activities between institutions, teachers, researchers and students. It is expected that the best Spanish experts of each subject will participate in the courses, but the presence of workshops and seminars open the way for the incorporation of international experts. A cooperative effort and a modular design are the key elements that have allowed maintaining the Spanish Interuniversity Master and PhD program for more than a decade, providing a high level of quality and a unique possibility of being trained in Green Chemistry for many students. Internationalization, in particular at an European level, is an essential trend for the future.

Acknowledgements: The contribution from the Green Chemistry Network of Spain (http://redqs.s43.eatj.com/redqs/index.jsp) is essential. Research associated to this program is possible thanks to MINECO (CTQ2011-28903-C02, and 2012-38543-C03), GV (PROMETEO/2012/020) and UJI (P1·1B2013-37 and -38). Educational funding from UJI is also acknowledged.

References1. B. Altava, M. I. Burguete and S. V. Luis, Educ. Quím., 2013, 24, 132 (in Spanish).2. B. Altava, M. I. Burguete, E. García-Verdugo and S. V. Luis, SmartQuimic, 2014, 1 (2), 68 (in Spanish).3. B. Altava, M. I. Burguete, E. García-Verdugo and S. V. Luis, Educational efforts in Green and Sustainable Chemistry from the

Spanish Network in Sustainable Chemistry, in Worldwide Trends in Green Chemistry Education, V. Zuin and L. Mammino Eds, Royal Society of Chemistry, in the press.

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O-B2-03-03

VIRTUAL RESEARCH COMMUNITY IN MOLECULAR AND MATERIALS SCIENCES AND TECHNOLOGIES FOR RESEARCH-BASED EDUCATION

A. Costantini1, A. Laganà2, C. Manuali2, N. Faginas Lago2, L. Pacifici2.1INFN, 06123, Perugia, Italy

2Department of Chemistry, Biology and Biotechnology, 06123, Perugia, ItalyPresenting author: [email protected]

The fast development of networked computing has led in recent years to the assemblage of a European Grid Infrastructure (https://www.egi.eu/about/) whose mission is to deliver integrated computing services to European researchers in order to drive innovation and enabling new solutions to meet present and future societal needs. Within EGI the Chemistry, Molecular Materials Science and Technologies (CMMST) community has structured itself as (https://documents.egi.eu/public/ShowDocument?docid=2221) a Virtual Research Community (VRC).

The CMMST VRC is working at gathering together software tools and computer applications aimed at facilitating the implementation of Service Oriented approaches grounded on electronic structure packages (like GAMESS, GAUSSIAN, MOLPRO, DALTON, MOLCAS, NWCHEM, TURBOMOLE, etc.), Molecular dynamics codes (RWAVEPR, MCTDH, FLUSS, ABC, VENUS, DL_POLY, GROMACS, CPMD, CP2K, NAMD, etc.).

In order to support the offering of services to the members of the VRCs EGI has just launched a call for proposals aimed at establishing thematic Competence Centres one of which will be addressed to the CMMST community. An important component of the CMMST VRC is the European Chemistry Thematic Network (ECTN) Association (http://ectn-assoc.cpe.fr/) whose Virtual Education Community (VEC) standing committee is strongly committed to support the development of modern services to research based education.

In particular, the CMMST competence centre will be heavily engaged in implementing competitive/collaborative models of designing and developing educational software, introducing community tools allowing Quality of Service (QoS) [1] selection of educational products, establishing a community credit system [2] to reward collaborative work, connecting the activities of public education Institutions to sector spinoffs and Small medium esterprises by exploiting the outcomes of its research activities.

References1. C. Manuali, A. Laganà, GRIF: A New Collaborative Framework for a Web Service Approach to Grid Empowered Calculations, Future Generation of Computer Systems, 27(3), 315-318 (2011)2. C. Manuali, A. Laganà, A Grid Credit System Empowering Virtual Research Communities Sustainability, Lecture Notes Computer Science 6784, 397-411 (2011)

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O-B3-01-02

DESIGNING SCIENTIFIC PRESENTATIONS: A TOOLBOX FOR RESEARCHERS

Fréderique Backaert1

1Department for Organic Chemistry, Ghent University, 9000 Ghent, BelgiumPresenting author: [email protected]

Whether you are an experienced speaker or not, everybody knows the feeling, the last five minutes before your scientific lecture starts. A combination of excitement, doubts, fears and nervousness kicks in, all of them able to create an unfavorable effect on your oral communication. Even more, during your presentation, you have to entertain your audience for the whole lecture time, both vocally and visually.

This lecture will provide tools for researchers giving scientific presentations including tips and tricks on how to become a good or better speaker and to make your presentation more attractive and inspiring for the audience [1].

Furthermore, questions and practical problems from the audience will be answered.

References

1. a) M. Davis “Scientific Papers and Presentations” 2nd edition (2006), Elsevier; b) M. Carter “Designing science presentations: a visual guide for figures, papers, slides, posters and more” 1st edition (2013), Elsevier.

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O-B3-01-03

You and your virtual self

Menno de WaalLife Science and Chemistry, Amsterdam Profession Institute, Amsterdam The Netherlands

In everyday life you create an image, learn skills and build a network. Combine these things, put it on a digital profile and you are virtual. The most important thing is to create a positive image, by being conscious of yourself. Easily said, know yourself and your public. You need to know who you are, to be able to sell and present yourself to a company or research group. What are your qualities and skills? And above all, how to describe your underdeveloped skills in a positive way?

Facebook, Google and LinkedIn provide others with your profile and a view in your life. These social media can be fun to have, easy methods of communication and a great way to build your network. But there is more to presenting yourself virtually. The first thing most managers do these days, is digital research. So what are the do’s and don’ts in presenting yourself through social media?

Describing your underdeveloped skills is a skill itself. By exploring your qualities and competencies, you can discover how others see you. A skill which is a quality to you, can be perceived differently by others. E.g. enthusiasm can be experienced as chaotic or wild, being helpful can be perceived as interference.

You and your virtual self are dynamic. Adjust your profile constantly to create the desired image. Be aware of yourself and the way others may perceive you.

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O-B3-02-01

Solving World Challenges through Chemistry: Research, Entrepreneurship and Leadership

J. Garcia-Martinez

Department of Inorganic Chemistry. University of Alicante. Alicante. 03690. Spain Presenting author: [email protected], www.nanomol.es, www.rivetechnology.com

We are all facing unprecedented challenges as our pressure on natural resources is increasing, the world population is exploding and global issues are becoming more complex and interconnected. Science and technology in general and chemistry in particular have been very effective in providing solutions in the past, from the green revolution to antibiotics. However, we need to find better more effective ways to quickly and effectively make discoveries widely available to the millions of people who desperately need them.

There is still a significant gap between academia and industry that needs to be bridged by bold entrepreneurs able to connect these two worlds and successfully commercialize the new and exciting research carried out in universities.

In order to get there, science education, from primary school to college, needs to be reinvented to put the student at the center of the learning process and provide him or her with the skills needed to become a more complete and creative scientist.

Figure 1: From challenge to solution through research, entrepreneurship and leadership

During the presentation, some successful examples of the transition from university research to commercialization will be discussed including some practical tips and provocative ideas on how to go from challenge to solution through research, entrepreneurship and leadership so everybody will be able to benefit from better chemistry.

References1. E. Serrano-Torregrosa, J. Garcia-Martinez, The Chemical Element. Wiley-VCH (2011), http://

www.thechemicalelement.com/ 2. J. Garcia Martinez, The Third Way: Becoming an Academic Entrepreneur, Science, March 20,

2014 http://bit.ly/ODMOzC 3. J. Garcia Martinez, Questing for Blue Oceans, Science, March 10, 2012 http://bit.ly/1i9YO3O 4. J. Garcia Martinez, How can we take science out of its ivory tower?, World Economic Forum,

February 20, 2014 http://bit.ly/1mM8G7r 5. E. Serrano-Torregrosa, J. Garcia-Martinez, Chemistry Education, Wiley-VCH (2014)

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O-B3-03-01

ANALYTICAL CHEMISTRY: THE KEY TO PRESERVE ETHICS AND FAIRPLAY IN SPORTS

P. Van Eenoo1, K. Deventer1, W. Van Gansbeke1, M. Polet1, S. Esposito1, E. Tudela Palomar1, P. Van Renterghem1, L. Lootens1

1DoCoLab - UGent, BE-9052, Zwijnaarde, BelgiumPresenting author: [email protected]

The use of performance enhancing drugs in sports is in breach with the essential values and ethics of sport. Doping is therefore prohibited and testing is performed by the analysis of biological samples for the use of such drugs. In agreement with the Olympic motto “Citius, Altius, Fortius”(i.e. faster, higher, stronger) analytical chemists continuously develop faster, more sensitive and comprehensive methods.

As the range of products, potentially used by athletes, is ever expanding a wide range of analytical techniques is currently used in anti-doping laboratories accredited by the World Anti-Doping Agency (WADA).

Chromatography-mass spectrometry is the preferred technology of choice. Although this technology has been used since the 1970s on a routine basis by anti-doping laboratories, new methods are still developed to intensify the fight against doping. Among the latest evolutions are the use of GC-MS/MS for more sensitive target screening and the introduction of LC-HRMS for untargeted screening of doping agents. As the statute of limitation is now extended to ten years, long-term storage of samples –and eventual suspension- has no become a reality The use of LC-HRMS will allow the re-evaluation of acquired data from previously analyzed samples; allowing a more swift re-assessment of anti-doping samples and retrospective suspension of athletes who used ‘unknown’ doping agents at the time of control.

Since the nineties, the classes of prohibited substances have expanded from small molecules to high molecular weight peptides. Similar as to the groups of designer steroids, designer stimulants and synthetic cannabinoids, the class of peptides has expanded rapidly on the black market. Often these substances are sold legally via the internet thanks to loopholes in legislation. According to the regulations in sports, they are however prohibited and methods need to be developed for these substances.

During the presentation, the challenges, solutions and recent developments in the anti-doping field will be discussed; showing that analytical chemistry can affect the history of sports…

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O-B3-03-02

Making your job application work for you

Marie ChapmanMember Networks Specialist

The Royal Society of [email protected]

Full of handy hints and tips for maximizing your chances of landing your dream job, this talk covers topics such as finding your chosen career path, writing an eye-catching CV and job application, and suggested ‘do’s and don’ts’ for interviews; all with the aim of increasing your chances of successfully applying for the job you want.

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O-B3-03-03

„Commune“ mistakes in scientific English

Sarah RuthvenManaging Editor

The Royal Society of Chemistry, Cambridge, [email protected]

This lecture will look at the processes that a paper goes through after acceptance at the Royal Society of Chemistry, highlighting how Editors work with authors to produce a paper ready for publication. This will be an interactive session with tips on how you can clearly communicate your research in scientific papers.

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O-B3-04-01

CAREER WORKSHOP: LEADERSHIP AND FOLLOWING

A. Schiller

Friedrich Schiller University Jena, Humboldtstrasse 8, 07743 Jena, Germanywww.schillermertens.de

[email protected]

If you are interested in leadership in science, then let’s make a workshop happen, start to finish, in 3 hours, and dissect some lessons: “A leader needs the guts to stand alone. But what he’s doing is so simple, it’s almost instructional. This is key. You must be easy to follow!” stated by Derek Sivers in his famous talk “Leadership Lessons from Dancing Guy”.

In this EYCN workshop, we will together reflect on some necessities of leadership in academia and in-dustry: How to communicate with people? How to delegate and how to listen? The workshop is highly interactive. We will install group activities with joint review sessions to get the most out of it for you! Trust the program, trust the dramaturgy, evaluate later.

The workshop will be lead by Alexander Schiller, chemist and Juniorprofessor at University Jena.

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O-B3-05-01

THE EUROPEAN YOUNG CHEMISTS’ NETWORK

F. Backaert1, V.-L. Ene2, L. Phelan3, A. Stefaniuk4, M.-C. Todasca2, A. Walshe5, K. Wijnbergen6

1Ghent University, 9000 Ghent, Belgium2Univeristy Politehnica of Bucharest, 011061 Bucharest, Romania

3Boston Scientific, Galway, Ireland

4Lodz University of Technology, 90-924 Lodz, Poland

5Trinity College Dublin, Dublin 2, Ireland

6CGI, 6801HA Arnhem, The NetherlandsPresenting author: [email protected]

The European Young Chemists’ Network (EYCN) is the young members division of the European Association for Chemical and Molecular Sciences (EuCheMS) and unites the young members divisions of 25 chemical societies in Europe. Whenever European young chemists are a member of an EYCN associated chemical society and younger than 35 years old, then these young chemists are automatically a member of EYCN. Anno 2014, EYCN counts more than 30000 members spread over 22 European countries from 25 chemical societies. Generally, our members study; do research on an academic level or work as young professionals in industry.

The aim of our organisation is to support information and knowledge transfer among European chemists, to accelerate the establishment of a strong professional network and to promote events organised by and for young chemists and a broad scientific-minded public. Even more, we create a united voice towards policy makers regarding research funding, sustainability, education and innovation in Europe.

During this talk, EYCN’s on-going activities and projects will be showcased in order to increase the awareness of our actions spread over Europe, eventually leading to a higher benefit for our members and our industrial partners.

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O-C1-01-02

Nanostructured thermoelectric materials in the system Ge/Sb/Te with skutterudite-type and copper telluride precipitates

O. Oeckler,1 F. Fahrnbauer,1 S. Schwarzmüller,1 T. Rosenthal,2 G. Wagner.1

1) Leipzig University, Faculty of Chemistry and Mineralogy, IMKM, Scharnhorststr. 20,04275 Leipzig, Germany

2) LMU Munich, Department of Chemistry, Butenandtstr. 5-13, 81377 Munich, GermanyPresenting author: [email protected]

In recent years, micro- and nanocscale heterostructures have received increasing attention as highly efficient thermoelectric materials. Facile strategies for bottom-up synthesis are highly desirable. Quenching appropriate melts may involve exsolution processes that lead to nano-precipitates. This is an intriguing way towards enhanced phonon scattering without significant loss of electrical conductivity and, as a consequence, better thermoelectric performance.[1] Metastable phases (GeTe)nSb2Te3 (GST materials) exhibit pronounced intrinsic nano structures due to short-range defect ordering upon quenching.[2] These depend on the composition and the history of thermal treatment. Without perturbing the charge balance, Ge atoms in these compounds can be substituted by twice the amount of Cu atoms up to a certain extent; this reduces the vacancy concentration. Higher Cu contents in e. g. Cu2Ge11Sb2Te15 lead to a rocksalt-type (GeTe)~11Sb2Te3 matrix that contains precipitates of Cu2Te and probably other copper tellurides. In some samples, endotactic intergrowth of matrix and precipitates is observed in high-resolution transmission electron micrographs. The thermal conductivity is significantly reduced in comparison to the corresponding GST materials and the thermoelectric figure of merit (ZT) reaches values ≥ 1.6 at 500 °C.

Quenching GST melts with additional CoSb3 yields heterogeneous nanocomposites with skutterudite-type precipitates. GeTe partially replaces Sb in the crystal structure of CoSb3, distorting the characteristic Sb4 units and changing the electronic structure.[3] Both the crystal structure of the GST material and of the precipitates has been elucidated by synchrotron microdiffraction on crystallites that were preselected by transmission electron microscopy and space-resolved X-ray spectroscopy (EDX). For metastable (GeTe)19Sb2Te3, for example, the precipitation of CoSb2(GeTe)0.5 improves the ZT value by an order of magnitude at low temperatures. The Seebeck coefficient strongly depends on the concentration of the precipitates. The partial substitution of Sb by As further increases the electrical conductivity up to 80 % without a significant change of the Seebeck coefficient. This substitution also makes the system more robust concerning thermal treatment, i. e. repeated heating and cooling cycles. When phase transitions occur, the temperature-dependent changes of the Seebeck coefficient and the electrical as well as the thermal conductivity compensate each other up to a certain degree so that the characteristics of the ZT value change quite smoothly.

References

1. S.N. Guin, D.S. Negi, R. Datta, K. Biswas, J. Mater. Chem. A 2014, 2, 4324.

2. T. Rosenthal, M.N. Schneider, C. Stiewe, M. Döblinger, O. Oeckler, Chem. Mater. 2011, 23, 4349.

3. X. Su, H. Li, Q. Guo, X. Tang, Q. Zhang, C. Uher, J. Electron. Mater. 2011, 40, 1286.

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O-C1-01-03

LIGAND EXCHANGE ON TRANSITION METAL OXO CLUSTERS

Johannes Kreutzer, Ulrich Schubert

Institute of Materials Chemistry, Vienna University of Technology, 1060 WienGetreidemarkt 9, Austria

Transition metal oxo clusters find increasing interest in material science as nanosized building blocks, especially for inorganic-organic hybrid materials. When polymerizable ligands are attached to the cluster surface, the inorganic building blocks can be incorporated in polymers by covalent bonding. Numerous transition metal oxo clusters with polymerizable ligands were synthesized and used to obtain polymers with tailored properties.

Most of the clusters used as comonomers so far have a high number of polymerizable groups of the same kind on their surface, resulting in highly crosslinked polymers. Ligand exchange on transition metal oxo clusters is one way to control the ratio of functionalized and non-functionalized ligands and can lead to less crosslinked polymers. Furthermore it is possible to obtain clusters with more than one functional group in the ligand sphere in an easy-to-adjust ratio by ligand exchange reactions.

In this work we will present a detailed NMR study of exchange reactions on Zr/Ti oxo clusters with different carboxylic acids. Complementary we will present a DFT study on the electronic structure of the clusters and site selective effects which may influence the exchange reaction will be discussed. It will be shown how the crosslinking density of the polymer can be changed by adjusting the ratio of polymerizable and non-polymerizable ligands.

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O-C1-01-04

Molecular Chalcoxide-based Materials: Design Approach and Emergence of Functionality

H. N. Miras,1 L. Cronin.1

1School of Chemistry, University of Glasgow, G12 8QQ, Glasgow, UPresenting author: [email protected]

Polyoxometalates (POMs) have been the subject of a large number of studies due to their nanoscale size, versatile architectures and tunable electronic and physical properties, [1] as well as fundamental investigations of self-assembly in supramolecular chemistry [2]. Additionally, POMs are excellent models for the investigation and deeper understanding of the properties of infinite metal oxides. Based on the above observation, I discuss here the potential for rational design of a fundamentally new family of molecular chalcoxides (ChalcoPOMs), [(Mo2S2O2)x(XO3)y(OH)z]

-(2x-2y-z) (where X: S, Se, Te), [3] and the implications in chalcogenide chemistry and materials science. The molecular chalcoxides could play an important role in the development of new “intermediate” materials with a new range of interesting and configurable electronic properties [4].

Figure 1: LEFT: Space-filling representation of a selenite-based, {Mo16S16Se8}, chalcoxide ring. Colour code: Mo: light grey; Se: blue; S: yellow; O: red; RIGHT: Nyquist plot of the {Mo16S16Se8} at 90% RH and temperatures 30, 35, 40, 45, 50 and 55 oC.

References1. H. N. Miras, J. Yan, D.-L. Long and L. Cronin, Chem. Soc. Rev. 41, 7403 (2012).2. A. Sartorel, M. Carraro, G. Scorrano, B. S. Bassil, M. H. Dickman, B. Keita, L. Nadjo, U. Kortz and

M. Bonchio, Chem. Eur. J. 15, 7854 (2009).3. H.-Y. Zang, J.-J. Chen, D.-L. Long, L. Cronin and H. N. Miras, Adv. Mater. 25, 6245 (2013).4. H. N. Miras, Chem. Eur. J. 20, 0000 (2014) DOI: 10.1002/chem.201402407.

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O-C1-01-05

NANOSTRUCTURED CdS AND ZnS-BASED PHOTOCATALYSTS FOR WATER SPLITTING: EFFECT OF PREPARATION ON SURFACE,

CATALYTIC AND ELECTRONIC PROPERTIES

E. Balantseva1, G. Berlier1, A.M. Ferrari1, G. Trunfio2, F. Arena2, S. Coluccia1

1University of Turin, Department of Chemistry and NIS Centre of Excellence, 10125, Torino, Italy2Department of Industrial Chemistry and Materials Engineer, University of Messina, I98066,

Messina, Italy Presenting author: [email protected]

In the modern society, striving for the most economical environment, hydrogen plays an important role with its clean potential uses in fuel cells, modern automotive engines, etc. [1]. On this account, much attention is being paid on new ways for hydrogen production and the catalytic overall water splitting is emerging as a potential method. Although different systems have been tested, the lack of stable electrode materials makes the accomplishment of an economic electrolysis system complicated and far away from industrial applications [1]. CdS photocatalysts own adequate requirements for the oxi-reduction of water under visible light in presence of sacrificial agents, but it presents as main drawbacks its toxicity and environmental concern. Recent works have demonstrated that the main features for optimal catalysts are composition, high cristallinity and surface area, and small particle size [1-2]. On the other hand new doping strategies applied for electron levels engineering of semiconductors has shown promising results. Therefore, this study is aimed at developing and probing photocatalytic water reducing activity of: 1) new optimized CdS systems obtained via different synthesis routes; 2) new eco-friendly metal/doped ZnS nanoparticles.

NANOSTRUCTURED CdS AND ZnS-BASED PHOTOCATALYSTS FOR WATER

SPLITTING: EFFECT OF PREPARATION ON SURFACE, CATALYTIC AND

ELECTRONIC PROPERTIES

E. Balantseva1, G. Berlier1, A.M. Ferrari1, G. Trunfio2, F. Arena2, S. Coluccia1 1University of Turin, Department of Chemistry and NIS Centre of Excellence, 10125, Torino,

Italy 2Department of Industrial Chemistry and Materials Engineer, University of Messina, I98066,

Messina, Italy Presenting author: [email protected]

In the modern society, striving for the most economical environment, hydrogen plays an important role with its clean potential uses in fuel cells, modern automotive engines, etc. [1]. On this account, much attention is being paid on new ways for hydrogen production and the catalytic overall water splitting is emerging as a potential method. Although different systems have been tested, the lack of stable electrode materials makes the accomplishment of an economic electrolysis system complicated and far away from industrial applications [1]. CdS photocatalysts own adequate requirements for the oxi-reduction of water under visible light in presence of sacrificial agents, but it presents as main drawbacks its toxicity and environmental concern. Recent works have demonstrated that the main features for optimal catalysts are composition, high cristallinity and surface area, and small particle size [1-2]. On the other hand new doping strategies applied for electron levels engineering of semiconductors has shown promising results. Therefore, this study is aimed at developing and probing photocatalytic water reducing activity of: 1) new optimized CdS systems obtained via different synthesis routes; 2) new eco-friendly metal/doped ZnS nanoparticles.

Figure 1: From left to right: employ of solar collectors for thermo-chemical activation of water; photocatalytic cycle employing sacrificial agents; interaction of the (110) ZnS surface with H2O molecules

The obtained systems were characterized by XRD, BET, TEM, FTIR and UV-Vis spectroscopies for chemical composition, structural and textural features, while their reactivity was tested using a photoreactor properly designed to maximize the radiation flux and minimize interphase diffusional resistances. Moreover, for a deeper understanding of the mechanisms involved in the doping strategy (band engineering) and photocatlytic activity (surface description) density functional theory (DFT) periodic calculations were employed. Computed results were compared with FTIR, UV-Vis and luminescence spectroscopy data recorded on particles synthesized in our laboratory.

References 1. A. Kudo, Y. Miseki. Chem. Soc. Rev., 38, 253-278. (2009). 2. K. Maeda, K. Domen. Chem. Mater., 22, 612-623 (2010).

The obtained systems were characterized by XRD, BET, TEM, FTIR and UV-Vis spectroscopies for chemical composition, structural and textural features, while their reactivity was tested using a photoreactor properly designed to maximize the radiation flux and minimize interphase diffusional resistances. Moreover, for a deeper understanding of the mechanisms involved in the doping strategy (band engineering) and photocatlytic activity (surface description) density functional theory (DFT) periodic calculations were employed. Computed results were compared with FTIR, UV-Vis and luminescence spectroscopy data recorded on particles synthesized in our laboratory.

References1. A. Kudo, Y. Miseki. Chem. Soc. Rev., 38, 253-278. (2009).2. K. Maeda, K. Domen. Chem. Mater., 22, 612-623 (2010).

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O-C1-01-06

A NOVEL HYBRID ORGANIC/INORGANIC COPPER(II)- DIPHOSPHO-NATE COMPLEX [{Cu2(4,4’-Bpy)}O3PC10H6PO3]; SYNTHESIS, STRUCTURE,

AND MAGNETIC PROPERTIES

A. Bulut1, G. Yucesan2

1Department of Chemistry, Bogazici University, 34342, Bebek-Istanbul, Turkey2Department of Bioengineering, Yildiz Technical University,34220, Davutpasa-Istanbul

Metal organic frameworks (MOF’s) are important type of organic/inorganic hybrit molecules perfor-ming wide variety of duties ranging from small molecule storage for renewable energy purposes to CO2 capture and catalysis due to their highly porous nature [1,2]. The synthesis of this group of materials mostly relies on the hydrothermal reactions of aromatic carboxylic acids with selected transition me-tals. Aromatic phosphonic acids form strong compounds with the transition metals and they are the strongest candidates to be studied for the synthesis of novel MOF materials [3,4]. In this study, we synt-hesized a new aromatic phosphonic acid using a modified Arbuzov reaction; Napthalene-1,4-dylbis(p-hosphonicacid). This synthesized aromatic phosphonic acid was reacted with copper under hydrother-mal reaction conditions under autogeneous pressure to obtain a novel organic/inorganic hybrit material. The structure of the crystal obtained after hydrothermal reaction was solved using single crystal X-ray diffraction and the structure is further confirmed by FTIR. DSC/TGA-FTIR and magnetic analysis also performed on the molecule. Small molecule storage properties is still under investigation.

Figure 1: A view of the structure of [{Cu2(4,4’-Bpy)}O3PC10H6PO3]

References1. S. Ushak, E. Spodine, E. Le Fur, D. Venegas-Yazigi, J.-Y. Pivan, W. Schnelle, R. Cardoso-Gil and R. Kniep, Inorg.Chem, 45; 5393-5398 (2006)2. G. Yucesan, W. Ouellette, Y.H. Chuang and J. Zubieta, Inorganica Chimica Acta, 360; 1502-1509 (2007)3. G. Yucesan, J. E. Valeich, H. Liu, W. Ouellette, C. J. O’connor and J. Zubieta, Inorganica Chimica Acta, 362, 1831-1839 (2009)4. D.-G. Ding, M.-C. Yin, H.-J. Lu, Y.-T. Fan, H.-W. Hou and Y.-T. Wang, Journal of Solid State Chem-istry, 179; 747–752 (2006)

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O-C1-02-02

Growth Phenomena of Inorganic Semiconducting Nanowires Using Solid Seeds

S. Barth1, M. S. Seifner1

1 Vienna University of Technology, 1060, Vienna, Austria.Presenting author: [email protected]

A high degree of experimental control over morphology, dimension, crystallographic phase and orientation has been achieved to date [1]; however some fundamental issues, such as defect control and integration issues, are not sufficiently solved yet. The presented lecture will focus on Ge and In2O3 model systems, which are formed by a metal-supported growth strategy. The nanowires investigated are predominantly grown by CVD techniques using molecular sources. The choice of the metal seed offers unique opportunities to modify the structure and properties of the growing material. Metal-seeded growth of 1D semiconductor nanostructures is still a very active field of research, despite the huge progress which has been made in understanding this fundamental phenomenon. However the transfer of crystallographic information from a nanoparticle seed to a growing nanowire has not been described in the literature. We investigated the formation of Ge and In2O3 nanowires using solid metal growth promoters a CVD process. We could demonstrate that (i) defects from a nanoparticle seed can be transferred to a growing semiconductor nanowire [2] and (ii) nanowires can be grown from solid seeds by a seed orientation dependent growth mechanism for non-alloying metal/nanowire materials combinations [3]. We defined requirements for the possibility of an effective defect transfer and pointed out which seeds could be used. We will discuss in this contribution the influence of solid growth seeds on the crystal quality and growth rate of these nanowires dependent of the choice of metallic growth promoter.

Figure 1: Schematics of (a) an orientation-dependent solid particle supported nanowire growth and (b) a defect transfer from nanoparticle to nanowires.

References[1] S. Barth, F. Hernandez-Ramirez, et al.. Prog. Mater. Sci. 2010, 55, 563.[2] S. Barth, J. J. Boland, J. D. Holmes, Nano Lett. 2011, 11, 1550.[3] S. Barth, M. S. Seifner, J. Bernardi, accepted.

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O-C1-02-03

The parent magnetic Mott-Jahn-Teller state of the high-Tc Cs3C60 superconductor studied by infrared spectroscopy

G. Klupp1,2, J. Horváth2, P. Matus2, K. Kamarás2, V. Kocsis3, I. Kézsmárki3, A. Y. Ganin4, M. J. Rosseinsky4, R. H. Colman1, R. H. Zadik1, M. D. Tzirakis1,

Y. Takabayashi1, K. Prassides1,5.1Department of Chemistry, Durham University, DH1 3LE, Durham, UK

2Institute for Solid State Physics and Optics, Wigner Research Centre for Physics, P.O. Box 49, 1525 Budapest, Hungary

3Department of Physics, Budapest University of Technology and Economics, Budafoki út 8, 1111 Budapest, Hungary

4Department of Chemistry, University of Liverpool, Liverpool L69 7ZD, UK5WPI Research Center, Advanced Institute for Materials Research, Tohoku University,

Sendai 980-8577, JapanPresenting author: [email protected]

The molecular material known to show superconductivity with the highest Tc of 38 K under pressure is the A15-structured polymorph of Cs3C60.[1] It is a non-conventional isotropic superconductor with electron correlations playing a decisive role in determining the electronic properties of its parent state which is found to be an antiferromagnetic Mott insulator at ambient pressure.[2] Here we present a study of the emergence of the magnetically ordered state in A15 Cs3C60 at TN = 47 K via infrared spec-troscopy. These results provide information about the symmetry of the constituent fulleride ions, and shed light on the interplay between crystal field effects and the molecular Jahn-Teller distortion. Recently, x-ray diffraction measurements found a subtle structural change that occurs at the onset of the antiferromagnetic ordering in the A15 polymorph of Cs3C60, implying that spin order is accompanied by orbital symmetry breaking. This structural change can be followed by infrared spectroscopy. Above TN the infrared measurements are in agreement with the presence of the dynamical Jahn-Teller effect implicated previously [3]. By comparing the infrared spectra of magnetically ordered and disordered phases, we are able to investigate the influence of the spin order on the Jahn-Teller distortion of the molecules in the Cs3C60 lattice and gain deeper understanding of magnetic Mott-Jahn-Teller insulators.

References1. A.Y. Ganin, Y. Takabayashi, Y. Z. Khimyak, S. Margadonna, A. Tamai, M. J. Rosseinsky, and K.

Prassides: Nature Materials 7, 367 (2008).1. Y. Takabayashi, A. Y. Ganin, P. Jeglic, D. Arcon, T. Takano, Y. Iwasa, Y. Ohishi,

M. Takata, N. Takeshita, K. Prassides, and M. J. Rosseinsky, Science 323, 1585 (2009).2. G. Klupp, P. Matus, K. Kamarás, A. Y. Ganin, A. McLennan, M. J. Rosseinsky,

Y. Takabayashi, M. T. McDonald, and K. Prassides, Nature Communications 3, 912 (2012).

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O-C1-02-04

TIME DEPENDENT ASSEMBLY OF CLUSTER-IN-CLUSTER {AG12}-IN-{W76} POLYOXOMETALATES UNDER SUPRAMOLECULAR CONTROL

C. H. Zhan1, J. M. Cameron1, J. Gao1, J. Purcell1, D. L. Long1, L. Cronin.*1

1WestCHEM, School of Chemistry, The University of Glasgow, G12 8QQ, Glasgow, UK Presenting author: [email protected]

Polyoxometalates (POMs) occupy an unique ‘mesoscopic’ space between molecular oxoanions and infinite oxides, and offer unique possibilities for materials design at the nanoscale.[1-2] In POMs archi-tectural control can be achieved at the fragment level by carefully selecting the heteroanion templates. However, discriminating the self- assembly, aggregation and isolation of nanoscale POM species as a function of time, and whilst under supramolecular control, has proved especially difficult until now. We report here the time resolved supramolecular assembly of series of nanoscale polyoxotungstate (POW) clusters, from the same reaction, of the form: [H(10+m)Ag18Cl(Te3W38O134)2]n where n = 1 and m = 0 for compound 1 (after 4 days), n=2 and m = 3 for compound 2 (after 10 days) and n = ∞ and m = 5 for compound 3 (after 14 days). The system is based upon the {Te3W38} unit whereby two units self-organise around a single chloride template and, with silver cations, form a {Ag12} cluster giving a {Ag12}-in-{W76} cluster-in-cluster in compounds 1-3 which further aggregates mediated by supramo-lecular Ag-POM interactions to the cluster of clusters compounds in 2 and 3. The proposed mechanism for the formation of the clusters has been confirmed by ESI-MS studies. Further, control experiments demonstrate the crucial role that TeO3

2-, Cl-, and Ag+ play in the self-assembly compounds 1-3. This work serves to illustrate the vast potential of using soft cations like silver in the assembly of gigantic molecular metal oxide nanostructures.

Figure 1: The assembly of cluster-in-cluster {Ag12}-in-{W76} around a single chloride template (left) and the time resolved crystallization of compounds 1-3 (right).

References

1. T. Liu, E. Diemann, H. Li, A. W. M. Dress and A. Müller Nature 426, 59-62 (2003).

2. D. L. Long, R. Tsunashima and L. Cronin Angew. Chem. Int. Ed. 49, 1736-1758 (2010).

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O-C1-02-05

Gas Diffusion in a Porous Organic Cage: Analysis of Dynamic Pore Connectivity using Molecular Dynamics Simulations

D. Holden1, K. Jelfs2, M. Haranczyk3, A. Cooper1.1University of Liverpool, L69 7ZD, Liverpool, United Kingdom

2Department of Chemistry, SW7 2AZ, Imperial College London, London, United Kingdom3Computational Research Division, CA 94720, Lawrence Berkeley National Laboratory, Berkeley


Most organic molecules pack in such a way to minimize free space therefore exhibiting minimal void volume, and hence permanent porosity is rare. However, previously we have shown that tetrahedral organic cages can be synthesized and then desolvated to generate porous crystals that adsorb small guest molecules such as nitrogen, hydrogen, methane and carbon dioxide.1 We have also shown that it is possible to control the particle size of these systems by altering the building blocks used within the makeup of the material.2 These all exhibit a 3D-di-amondoid pore network and by altering the modulus there is an impact on the pore size; as a result the diffusion of gases through them changes.

Upon the generation of a bespoke force field, it has been possible to simulate how the diffusion of small gases alter dependent on their particle size.3 Molecular dynamics simulations were subsequently used to investigate the diffusion of six small gas molecules in a crystalline porous organic cage, CC3.4 A flexible host model was used to simulate transient channel formation, the effects of which are reflected in the calculated diffusion coefficients for the six gases of 5.64 × 10-8, 5.94 × 10-9, 2.60 × 10-9, 9.60 × 10-9, 2.40 × 10-9, and 1.83 × 10-10 m2 s-1, respectively, for H2, N2, CO2, CH4, Kr, and Xe. By contrast, a larger gas molecule, SF6, was predicted to be unable to diffuse in the pores of this material. We then introduce a new method – a void space histogram – to analyze dynamic pore topologies and to graphically illustrate the structural factors determining guest diffusion. This new technique has unlocked phenomena such as gas selectivity, rare-event hopping and diffusion of gases to regions previously considered inaccessible, via the formation of transient pore channels; all of which help to rationalize experimen-tal observations. The overall aim is to predict materials that show good selectivity to one gas over another.

Gas Diffusion in a Porous Organic Cage: Analysis of Dynamic Pore Connectivity

using Molecular Dynamics Simulations

D. Holden1, K. Jelfs2, M. Haranczyk3, A. Cooper1. 1University of Liverpool, L69 7ZD, Liverpool, United Kingdom

2Department of Chemistry, SW7 2AZ, Imperial College London, London, United Kingdom

3Computational Research Division, CA 94720, Lawrence Berkeley National Laboratory, Berkeley


Most organic molecules pack in such a way to minimize free space therefore exhibiting minimal void volume, and hence permanent porosity is rare. However, previously we have shown that tetrahedral organic cages can be synthesized and then desolvated to generate porous crystals that adsorb small guest molecules such as nitrogen, hydrogen, methane and carbon dioxide.1 We have also shown that it is possible to control the particle size of these systems by altering the building blocks used within the makeup of the material.2 These all exhibit a 3D-diamondoid pore network and by altering the modulus there is an impact on the pore size; as a result the diffusion of gases through them changes.

Upon the generation of a bespoke force field, it has been possible to simulate how the diffusion of small gases alter dependent on their particle size.3 Molecular dynamics simulations were subsequently used to investigate the diffusion of six small gas molecules in a crystalline porous organic cage, CC3.4 A flexible host model was used to simulate transient channel formation, the effects of which are reflected in the calculated diffusion coefficients for the six gases of 5.64 × 10-8, 5.94 × 10-9, 2.60 × 10-9, 9.60 × 10-9, 2.40 × 10-9, and 1.83 × 10-10 m2 s-1, respectively, for H2, N2, CO2, CH4, Kr, and Xe. By contrast, a larger gas molecule, SF6, was predicted to be unable to diffuse in the pores of this material. We then introduce a new method – a void space histogram – to analyze dynamic pore topologies and to graphically illustrate the structural factors determining guest diffusion. This new technique has unlocked phenomena such as gas selectivity, rare-event hopping and diffusion of gases to regions previously considered inaccessible, via the formation of transient pore channels; all of which help to rationalize experimental observations. The overall aim is to predict materials that show good selectivity to one gas over another.

Figure 1. a) Scheme showing generation of pore topology from the connectivity of adjacent CC3 molecules in the supercell. b) The gray square boxes represents each CC3 subunit, and

a)

b)

c)

Figure 1. a) Scheme showing generation of pore topology from the connectivity of adjacent CC3 molecules in the supercell. b) The gray square boxes represents each CC3 subunit, and the two distinct void cavities (the cage cavities and the inter-cage voids) are colored green. If these voids start to overlap then transient channels are formed between them until, c), a 3-D diamondoid network is formed across the 2 × 2 × 2 CC3 supercell.

References1. Tozawa, T.; Jones, J. T. A.; Swamy, S. I.; Jiang, S.; Adams, D. J.; Shakespeare, S.; Clowes, R.; Bradshaw, D.; Hasell, T.; Chong,

S. Y.; Tang, C.; Thompson, S.; Parker, J.; Trewin, A.; Bacsa, J.; Slawin, A. M. Z.; Steiner, A.; Cooper, A. I. Porous Organic Cages. Nature Mater. 2009, 8, 973–978.

2. Hasell, T.; Culshaw, J. L.; Chong, S. Y.; Schmidtmann, M.; Little, M. A.; Jelfs, K. E.; Pyzer-Knapp, E. O.; Shepherd, H.; Adams, D. J.; Day, G. M.; Cooper, A. I. Controlling the Crystallization of Porous Organic Cages: Molecular Analogs of Isoreticular Frameworks Using Shape-Specific Directing Solvents. J. Am. Chem. Soc. 2014, 136, 1438–1448.

3. Holden, D.; Jelfs, K. E.; Cooper, A. I.; Trewin, A.; Willock, D. J. Bespoke Force Field for Simulating the Molecular Dynamics of Porous Organic Cages. J. Phys. Chem. C 2012, 116, 16639–16651.

4. Holden, D.; Jelfs, K. E.; Trewin, A.; Willock, D. J.; Haranczyk, M.; Cooper, A. I. Gas Diffusion in a Porous Organic Cage: Analysis of Dynamic Pore Connectivity using Molecular Dynamics Simulations. J. Phys. Chem. C 2014, Accepted.

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O-C1-03-01

Engineering the growth of gold on the tips of palladium nanoparticles

Guangchao Zheng1, Enrique Carbó-Argibay3, Elisa Gonzalez-Romero4, Isabel. Pastoriza-Santos1, Jorge. Pérez-Juste1, Luis M. Liz-Marzán1,2

1 Departamento de Química Física, Universidade de Vigo, 36310 Vigo, Spain2 BNP Laboratory, CIC biomaGUNE, Paseo de Miramón 182, 20009 Donostia, Spain

3 Analytical and food chemistry, university of vigo, 36310 Vigo, Spain4 INL- International Iberian Nanotechnology Laboratory, Avenida Mestre José Veiga s/n, 4715-330

Braga, PortugalPresenting author: [email protected]

A key step in metal nanocrystal synthesis is the control over its shape and composition. Therefore the ability to obtain materials with nanosized domains within a single hybrid nanoparticle offers a promising way to engineer nanomaterials. Such hybrid nanomaterials could present multiple functionalities or enhance the properties of one particular domain. For instance, recent advances in nanocrystal synthesis allow the shape control of palladium nanoparticles in organic media.[1] The large surface-to-volume ratio and the present of sharp corners confers better catalytic properties to such nanoparticles. In this context, in the present study we show a novel approach to synthesize Pd-Au hybrid systems based on the selective growth of gold on the tips of the Pd nanoparticles. Through the proposed methodology the size of the gold domain can be nicely tuned (see Figure 1). The electrocatalytic activity of the different Au-Pd hybrids has been investigated.

Figure 1: (a)(d) are the HRTEM of the hybrids; (b)(c) STEM-EDS elemental mapping performed by HRTEM at a HAADF-STEM image responding to (a) (d) separately.

References1. Zhiqiang Niu1, Angew. Chem. Int. Ed. , 50, 6315 –6319(2014).

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O-C1-03-02

NEW MULTIMETALLIC ASSEMBLIES AS PHOTOLUMINESCENT MATERIALS

A. Duerrbeck1,2, Nicholas Long1, Andy Hor.2

1Imperial College London, Department of Chemistry, UK2National University of Singapore, Department of Chemistry, Singapore


The preparation of metal-coordination compounds between pybox (pyridine-bis-oxazoline) as the ligand and Eu(III) and Tb(III) ions has recently attracted great interest.1 High quantum yields and efficient ligand-to-metal energy transfer make pybox-related ligands good sensitizers for lanthanide emission. They are promising materials for performance-enhanced photoactive devices. However, the research in the field to date, has shown that modifications of the pybox ligand do not result in remarkable changes in the photoluminescent properties, limiting the diversity of these complexes and therefore, their potential for further application. The main focus of this project is therefore, the synthesis of new dumbbell-shaped bis-tridentate ditopic ligands and the subsequent preparation of photoluminescent lanthanide coordination networks (Figure 1).

NEW MULTIMETALLIC ASSEMBLIES AS PHOTOLUMINESCENT MATERIALS

A. Duerrbeck1,2, Nicholas Long1, Andy Hor.2 1Imperial College London, Department of Chemistry, UK

2National University of Singapore, Department of Chemistry, Singapore Presenting author: [email protected]

The preparation of metal-coordination compounds between pybox (pyridine-bis-oxazoline) as the ligand and Eu(III) and Tb(III) ions has recently attracted great interest.1 High quantum yields and efficient ligand-to-metal energy transfer make pybox-related ligands good sensitizers for lanthanide emission. They are promising materials for performance-enhanced photoactive devices. However, the research in the field to date, has shown that modifications of the pybox ligand do not result in remarkable changes in the photoluminescent properties, limiting the diversity of these complexes and therefore, their potential for further application. The main focus of this project is therefore, the synthesis of new dumbbell-shaped bis-tridentate ditopic ligands and the subsequent preparation of photoluminescent lanthanide coordination networks (Figure 1).

Figure 1. Schematic presentation of the preparation of lanthanide coordination networks with pybox-related ditopic ligands.

Figure 2. Time-gated emission spectra of a ditopic pybox Eu(III) compound between 0.1 and 5µs and the overall lifetime decay curve (inset) up to 7ms.

To date, two new types of pybox-ligands, which have blue luminescence, have been synthesized under improved cross-coupling reaction conditions. Coordination of these ditopic ligands with Eu(III) and Tb(III) in different stoichiometries resulted in novel soluble photoluminescent materials. Time-gated emission studies have shown that the blue ligand fluorescence in these samples is completely quenched, indicating efficient energy transfer from the ligand to the lanthanide metal centre which lead to an improved quantum yield of about 68%. Furthermore, time-gated studies of the pybox Eu(III) compounds up to 5 µs showed distinct changes in the intensity ratio of the pure magnetic 5D0 – 7F1 and the symmetry dependent electonic 5D0 – 7F2 transitions (Figure 2), providing a window to assess the nature of the network structure in solution. These novel ditopic ligand-lanthanide network-based materials, having a controllable coordination sphere together with high quantum yields, are therefore promising for the preparation of performance-enhanced photoactive devices. References 1. A. Bettencourt-Dias, P.S. Barber, S. Bauer, Journal of the American Chemical Society, 134, (2012), 6987.

τ = 1.8ms

To date, two new types of pybox-ligands, which have blue luminescence, have been synthesized under improved cross-coupling reaction conditions. Coordination of these ditopic ligands with Eu(III) and Tb(III) in different stoichiometries resulted in novel soluble photoluminescent materials. Time-gated emission studies have shown that the blue ligand fluorescence in these samples is completely quenched, indicating efficient energy transfer from the ligand to the lanthanide metal centre which lead to an improved quantum yield of about 68%. Furthermore, time-gated studies of the pybox Eu(III) compounds up to 5 µs showed distinct changes in the intensity ratio of the pure magnetic 5D0 – 7F1 and the symmetry dependent electonic 5D0 – 7F2 transitions (Figure 2), providing a window to assess the nature of the network structure in solution. These novel ditopic ligand-lanthanide network-based materials, having a controllable coordination sphere together with high quantum yields, are therefore promising for the preparation of performance-enhanced photoactive devices.

References1. A. Bettencourt-Dias, P.S. Barber, S. Bauer, Journal of the American Chemical Society, 134, (2012),

6987.

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O-C1-03-03

CHEMISTRY IN NANOREACTORS: NANOCRYSTALLINE INORGANIC COMPOUNDS VIA MINIEMULSION

Paolo Dolcet1, Maurizio Casarin1, Silvia Gross1,2

1Dipartimento di Scienze Chimiche, Università degli Studi di Padova, via Marzolo, 1, 35131, Padova, Italy

2Istituto per l’Energetica e le Interfasi, IENI-CNR and INSTM, UdR, via Marzolo, 1, 35131, Padova, Italy


Colloidal systems are highly appealing to achieve a good control on inorganic nanoparticles size, size distribution, crystallinity and shape. Among them, emulsions play a leading role and, in more detail, miniemulsions (MEs) represent a promising way to achieve a good control on the features of the final materials. Thanks to the high shear forces applied during homogenization, these systems reach the minimum droplet size possible, diffusion and collision phenomena are hindered, and droplets maintain their identity. A ME thus represents an ensemble of 1018-1020 independent droplets, where a reaction can take place in a parallel fashion. In these last years we exploited inverse MEs for the syntheses of a wide variety of inorganic materials. For example, ZnO nanostructures were obtained at RT, through an easy and reproducible route, which also enabled controlled doping [1,2].A similar approach was applied to the preparation of other lanthanide-doped binary and ternary systems, i.e., sulphides (ZnS), halogenides (CaF2) and hydroxides (Ca(OH)2 and Mg(OH)2). These materials showed good doping control, interesting luminescence properties and low cytotoxic effects, leading to appealing systems with potential bioimaging applications.The ME approach was also exploited for the photodecomposition in confined space of a tailored single-source Au/TiO2 precursor, enhancing catalytic properties with respect with the same materials prepared in a bulk [3].

References[1] P. Dolcet, F. Latini, M. Casarin, A. Speghini, E. Tondello, C. Foss, S. Diodati, L. Verin, A.

Motta, S. Gross, Eur. J. Inorg. Chem. 2013, 2013, 2291–2300.

[2] P. Dolcet, M. Casarin, C. Maccato, L. Bovo, G. Ischia, S. Gialanella, F. Mancin, E. Tondello, S. Gross, J. Mater. Chem. 2012, 22, 1620–1626.

[3] N. A. Heutz, P. Dolcet, A. Birkner, M. Casarin, K. Merz, S. Gialanella, S. Gross, Nanoscale 2013, 5, 10534–41.

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O-C1-03-04

Planar and Twisted Polycyclic Aromatic Hydrocarbons with Pyrazine Rings

Aurelio Mateo-Alonso1,2

1 POLYMAT, University of the Basque Country UPV/EHU, Avenida de Tolosa 72, E-20018 Donostia-San Sebastian, Spain

2 Ikerbasque, Basque Foundation for Science, Bilbao, [email protected]

The most recent advances on planar and twisted polycyclic aromatic hydrocarbons with pyrazine rings, including synthetic routes, optoelectronic properties, self-organising properties, and potential applications of these molecular materials will be discussed.

References[8] S. More, R. Bhosale, and A. Mateo-Alonso Chem. Eur. J., 2014, DOI: 10.1002/chem.201304461.[7] S. More, S. Choudhary, A. Higelin, I. Krossing, M. Melle-Franco and A. Mateo-Alonso Chem.

Comm., 2014, 50, 1976-1979.[6] S. Choudhary, C. Gozalvez, A. Higelin, I. Krossing, M. Melle-Franco and A. Mateo-Alonso Chem.

Eur. J., 2014, 20, 1525-1528.[5] M. Grzelczak, N. Kulisic, M. Prato and A. Mateo-Alonso Part. Part. Syst. Charact., 2014, 31,

121–125.[4] S. More, R. Bhosale, S. Choudhary, A. Mateo-Alonso Org. Lett. 2012, 14, 4170-4173.[3] N. Kulisic, S. More, and A. Mateo-Alonso Chem. Comm. 2011, 47, 514-516.[2] M. Grzelczak, N. Kulisic, M. Prato and A. Mateo-Alonso Chem. Comm. 2010, 46, 9122-9124.[1] A. Mateo-Alonso N. Kulisic, G. Valenti, M. Marcaccio, F. Paolucci and M. Prato Chem. Asian J.

2010, 5, 482-485.

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O-C1-03-05

INVESTIGATIONS ON THE FUNDAMENTAL THERMO- AND PIEZO-MECHANICAL PROPERTIES OF SOFT METAL-ORGANIC FRAMEWORKS

Sebastian Henke and Anthony K. Cheetham

University of Cambridge, Department of Materials Science and Metallurgy, CB3 0FS, Cambridge, United Kingdom


Metal-organic frameworks (MOFs) represent a young family of porous materials showing huge potential for various applications ranging from gas storage to catalysis and drug delivery. Some of these zeolite-like inorganic-organic frameworks are flexible and exhibit reversible structural transitions in dependence on external stimuli, such as guest adsorption or changes in temperature and mechanical pressure [1]. Based on their unique multi-stable nature these responsive MOFs, also called soft porous crystals (SPCs), represent the next generation of porous materials by combining responsiveness and selectivity with regular pore architectures. Even though the guest-responsive behaviour of various SPCs has been studied extensively in recent years, reports on their unprecedented thermal and mechanical properties are extremely rare [2,3]. Knowledge and understanding of these fundamental properties (including thermal expansion, Young’s modulus, bulk modulus) of this promising family of functional materials is urgently needed for any technological application and might pave the way for their application in selective sensing, separation and electronic devices.

Figure 1: (a) Representation of the structural variations in a [M2L2P]n SPC as a function of guest molecule adsorption. (b) Young’s moduli of the different guest-containing forms shown in panel a. (c) Thermal expansivity indicatrix for the DMF-containing phase.

We present single-crystal and powder X-ray diffraction studies on the temperature- and pressure-driven structural response of the important family of pillared-layered [M2L2P]n SPCs (Figure 1); with M = Co, Ni, Cu, Zn; L = linear dicarboxylate linker; P = neutral pillar. Extreme thermo- and piezo-mechanical behaviour (negative linear thermal expansion, ‘colossal’ positive thermal expansion, negative linear compressibility) is observed for selected [M2L2P]n frameworks. In addition, the mechanical properties (i.e. Young’s modulus, hardness) of these SPCs have been determined via single-crystal nanoindentation (Fig. 1b). Very large mechanical anisotropy is apparent depending on the variable network geometry of these flexible MOFs. Combining these data allows us to extract fundamental structure-mechanical property relationships for these fascinating responsive materials.

References1. S. Horike, S. Shimomura, S. Kitagawa, Nat. Chem., 2009, 1, 695.2. A. U. Ortiz, A. Boutin, A. H. Fuchs, F.-X. Coudert, Phys. Rev. Lett., 2012, 109, 195502. 3. S. Henke, A. Schneemann, R. A. Fischer, Adv. Funct. Mater., 2013, 23, 5990.

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O-C1-03-06

AQUEOUS SELF- AND CO-ASSEMBLY PROCESSES CONTROLLED BY HYDROPHOBIC INTERACTIONS

N. K. Allampally, M J. Mayoral, G. Fernandez

Institut für Organische Chemie and Center for Nanosystems Chemistry, Universtität Würzburg Am Hubland, 97074 Würzburg, Germany.


Cooperativity is a key mechanism involved in the aqueous self-assembly of various biological systems.[1] Herein, we show that cooperative self-assembly mechanisms in water can be controlled by tuning the balance between hydrophobic and hydrophilic fragments of the self-aggregating units[2] and by co-assembly with guest molecules of appropriate size.[3]

Figure 1: Cartoon representation of the self-assembly of one of the amphiphilic systems described in our group into H-type aggregates and its guest-dependent encapsulation processes

References1. F. Huber, J. Schnauß, S. Rönicke, P. Rauch, K. Müller, C. Fütterer, J. Käs, Adv. Phys. 62, 1 (2013).2. T. Rudolph, N. K. Allampally, G. Fernández, F. H. Schacher, Angew. Chem., submitted.3. N. K. Allampally, A. Florian, M. J. Mayoral, C. Rest, V. Stepanenko, G. Fernández, Chem. Eur. J., 20, 10.1002/chem.201402077 (2014).

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O-C1-04-02

New multinary selenides with pavonite-like and lillianite-like structures

F. Heinke,1 P.Urban,1 C. Fraunhofer,2 G. Wagner,1 O. Oeckler.1

1) Leipzig University,Faculty of Chemistry and Mineralogy, IMKM, Scharnhorststraße 20, 04275 Leipzig, Germany

2) LMU Munich, Department of Chemistry, Butenandtstr. 5-13, 81377 Munich, GermanyPresenting author: [email protected]

Binary lead chalcogenides (except oxides) crystallize in the NaCl structure type. The chalcogenides of Sb and Bi are not isostructural:[1] The sulfides form structures characterized by infinite chains, whereas the tellurides form layered structures. Bi2Se3 may crystallize in both structure types.[2] A large variety of solid solutions in the system Bi-Pb-X (X = S, Se, Te) can formally be derived by the combination of the corresponding binary compounds. As known from the well-investigated system Pb-Bi-S, a variety of such phases can be obtained by heterovalent substitution 2 Pb2+ by Ag+ + Bi3+).[3] In the system Ag/Bi/Pb/Se, new compounds can be obtained by rapid cooling. Quenching a melt with nominal composition Ag0.61Pb0.68Bi2.28Se5 yields multi-phase samples that contain small single crystals. These were investigated using transmission electron microscopy and X-ray spectroscopy (EDX) as well as diffraction experiments with microfocussed synchrotron radiation. The new compound Ag3Pb4Bi11Se22 crystallizes in the a structure type closely related to that of pavonite, AgBi3S5 (space group C2/m, a = 13.85 Å, b = 4.211 Å, c = 19.72 Å, β = 104.6°, R1(obs)=0.035). The cation distribution is not accessible by conventional X-ray experiments as Pb and Bi lack sufficient scattering contrast; it was analyzed by bond-valence sum calculations.There is no scattering-contrast problem in the system Sn-Bi-Se. In the pseudo-binary phase diagram SnSe/Bi2Se3,

[4] a phase “X” in the compositional range (SnSe)nBi2Se3 with 0.8 £ n £ 3 was reported but not investigated yet. In this range, three new phases were now characterized. All of them crystallize in structure types derived from that of lillianite (Pb3Sb2S6). They consist of distorted NaCl-like slabs of different thickness interconnected by tropochemical twin boundaries and can be described with established concepts of “sulfosalt” crystal chemistry.[3,5] (SnSe)~2Bi2Se3 crystallizes in the heyrovskite structure type (Cmcm, a = 4.193 Å, b = 13.87 Å, c = 32.01 Å, R1(obs) = 0.043), (SnSe)~1.5Bi2Se3 in the lillianite structure type (Cmcm, a = 4.196 Å, b = 13.83 Å, c = 21.19 Å, R1(obs) = 0.037) and (SnSe)~0.9Bi2Se3 in the KSn5Bi5Se13 structure type (C2/m, a = 13.85 Å, b = 4.196 Å, c = 23.31 Å, β = 98.8°, R1(obs) = 0.043). Unlike the corresponding lillianite-like sulfides they contain cation vacancies distributed in the structures which might lead to an improvement of their thermoelectric properties.

References1. a) S. Ohba, S. Sato, Y. Saito, Acta Crystallogr. B39, 312 (1983); b) T. L. Anderson, H. B. Krause,

Acta Crystallogr. B30, 1307 (1974).2. a) C. P. Vicente, J. L. Tirado, K. Adouby, J. C. Jumas, A. A. Touré, G. Kra, Inorg. Chem. 38, 2131

(1999); b) R. Caracas, X. Gonze, Phys. Chem. Miner. 32, 295 (2005).3. A. Skowron, R. J. D. Tilley, J. Solid State Chem. 85, 235 (1990).4. K. Adouby, M. L. Elidrissi Moubtassim, C. P. Vicente, J. C. Jumas, A. A. Touré, J. Alloys Compd.

453, 161 (2008).5. J. Takagi, Y. Takéuchi, Acta Crystallogr. B28, 649 (1972).

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O-C1-04-03

Characterization and Identification of Electrides

Eduard Matito, Verònica Postils, Marc Garcia-Borràs, Miquel Solà and Josep M. Luis

Institut de Química Computaciona i Catàlisi (IQCC), Campus de Montilivi, Universitat de Girona, 17071 Girona, Spain

The electrides1-2 are intriguing chemical species with an electron not formally assigned to any atom. This situation is completely different to that given in a metal where the electrons are delocalized be-tween positively charged metal ions. The electron in an electride acts as a formal anion, which is bonded to positively charged species in the molecule. This particular feature of electrides prompts very particular chemical and physical properties: they are powerful reducing reagents, exhibit exalted elec-tric linear and non-linear optical properties as well as a particular magnetic behavior. In this work, we analyze the electronic structure and the identification of several electride structures by means of the Quantum Theory of Atoms in Molecules (QTAIM) and the Electron Localization Func-tion (ELF).3 Our results show that these tools make possible the classification of candidate species as electrides or not. It was already proved that one could distinguish the electride behavior in insulating high-pressure forms of alkali metals from ELF analysis4 but now we show that with QTAIM and ELF is possible to characterize the electride behavior in all sorts of molecules. Thus far, only a few electrides have been synthesized. This work7 uncovers important details of the electronic structure of electrides thus helping to design new electrides with enhanced properties.

[1] Dye, J. L. Science, 2003, 301, 607-608[2] Dye, J. L. Science, 1990, 247, 663[3] Matito, E.; Solà, M. Coord. Chem. Rev., 2009, 253, 647-665[4] Marqués et al., Phys Rev. Lett. 2009, 103, 115501[5] Kim SW., Shimoyama T., Hosono H. Science 333, 71 (2011)[6] Lee K., Kim SW., Toda Y., Matsuishi S. and Hosono H. Nature 494, 336 (2013) [7] Postils V., Garcia-Borràs M., Solà M. Luis JM. and Matito E.; in preparation.

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O-C1-04-04

HIERARCHICAL SUPRAMOLECULAR STRUCTURES INDUCED BY COOPERATIVE PROCESSES

N. K. Allampally, C. Rest, V. Stepanenko, M. J. Mayoral, K. Fucke, G. Fernández*

Institut für Organische Chemie and Center for Nanosystems Chemistry, Universität Würzburg am Hubland, 97074 Würzburg (Germany)[email protected]

Natural macromolecules have the extraordinary ability to self-assemble through cooperative forces into well-defined nanostructures in a controlled fashion.[1] In our group, we have exploited several strategies to construct well-defined cooperative self-assembled structures based on co-assembly processes,[2] metallophilic interactions,[3] and CH∙∙∙X hydrogen bonding.[4] The application of these concepts in drug delivery is currently underway.

Figure 1: Selected examples of hierarchical supramolecular structures described in our group driven by Pd∙∙∙Pd interactions (a) and unconventional CH∙∙∙X hydrogen bonding (b).

References1. T. F. A. de Greef, M. M. J. Smulders, M. Wolffs, A. P. H. J. Schenning, R. P. Sijbesma, E. W. Meijer,

Chem. Rev. 109, 5687 (2009).2. a) N. K. Allampally, A. Florian, M. J. Mayoral, C. Rest, V. Stepanenko, G. Fernández, Chem. Eur. J.,

20, 10.1002/chem.201402077 (2014). b) M. J. Mayoral, C. Rest, J. Schellheimer, V. Stepanenko, G. Fernández, Chem. Eur. J. 18, 15607 (2012).

3. a) M. J. Mayoral, G. Fernández, Chem. Sci. 3, 1395 (2012). b) M. J. Mayoral, C. Rest, V. Stepanenko, J. Schellheimer, R. Q. Albuquerque, G. Fernández, J. Am. Chem. Soc. 135, 2148 (2013).

4. C. Rest, M. J. Mayoral, K. Fucke, V. Stepanenko, J. Schellheimer, G. Fernández, Angew. Chem. Int. Ed. 53, 700 (2014).

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O-C2-01-02

Turkevich revised – answers to mechanistic key questions of a commonly used gold nanoparticles synthesis

M. Wuithschick1, A. Birnbaum1, K. Rademann, J. Polte.1

1Humboldt University of Berlin, Department of Chemistry, Brook-Taylor-Str. 2, 12489, Berlin, Germany


In the community of colloidal nanoparticles the Turkevich method is well known as one of the most commonly used syntheses of colloidal gold nanoparticles in aqueous solution [1]. The synthesis is based on the reduction of HAuCl4 with sodium citrate at elevated temperatures. During the past six decades, many modifications of the synthesis were developed which allowed the preparation of particles with different sizes and material properties [2]. These recipes were derived from systematic variations of synthesis parameters in a trial and error approach whereas a comprehensive understanding of the actual parameter influences on the particle growth mechanism is still missing. Though, such knowledge enables the directed modification of the synthesis parameters in order to produce gold nanoparticles with properties on demand, e.g. for biomedical applications.

From time-resolved small-angle X-ray scattering (SAXS) experiments, we deduced a principle growth mechanism of the Turkevich synthesis [3]. It was shown that particles are formed through a sequence of growth steps comprising a fast initial formation of small nuclei, coalescence into bigger seed particles, slow growth of seed particles sustained by ongoing reduction of Au3+ and subsequent fast reduction ending with the complete consumption of the precursor species.

In this contribution, we present the results of extensive SAXS and UV-vis studies which reveal a sophisticated correlation between growth mechanism and final particle size distribution by answering the following key questions: How do the different physicochemical processes in the colloidal solution influence the growth mechanism? How do the parameters influence the growth? What determines the final particle size? How can the final particle size be adjusted precisely?

Therefore, this contribution addresses (i) the comprehensive mechanistic understanding of the most commonly used gold nanoparticle synthesis and (ii) guidelines to a deliberate adjustment of the synthesis conditions to produce particles with sizes on demand.

References1. J. Turkevich, P.C. Stevenson, and J. Hillier, Discuss. Faraday Soc. 11, 55 (1951).2. S. Kumar, K.S. Gandhi, and R. Kumar, Ind. Eng. Chem. Res. 46, 312 (2007). 3. J. Polte, T. T. Ahner, F. Delissen, S. Sokolov, F. Emmerling, A. F. Thünemann, and R. Kraehnert, J.

Am. Chem. Soc. 132, 1296 (2010).

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NMR EVIDENCE FOR THE ROLE OF CITRATE ON THE STABILIZATION OF GOLD NANOPARTICLES

Hind Al-Johani1, Mohamad EL Eter1, Shiv Shankar Sangaru1, Edy Abou-Hamad1, Dalaver H Anjum1, Lyndon Emsley2, and Jean-Marie Basset1

1KAUST Catalysis Center and Division of Chemical and Life Sciences and Engineering, King Abdullah University of Science and Technology, Thuwal, 23955-6900, Saudi Arabia. 2Université

de Lyon, (CNRS/ENS-Lyon/UCB Lyon 1), Centre de RMN à Très Hauts Champs, 5 rue de la Doua, 69100 Villeurbanne, France.


Surface Organometallic 1has been successful in the last decades to create new molecular complexes at the surface of nanoparticles of metal. This was extremely helpful to understand some elementary steps of heterogeneous catalysis. This field benefited considerably from the recent advances in solid-state NMR. However this technique was largely applied to oxide supported organometallics2,3.{Le Roux, 2005 #538}{Le Roux, 2005 #2538} In fact the field of molecular understanding of heterogeneous catalysis would benefit considerably if the tools of SOMC could be extended to metallic materials. We demonstrate herein by SS NMR that citrate coordinates to gold nanoparticles by its carboxylate function predominantly in a bidentate mode at low coverage and a monodentate mode at high coverage. We also demonstrate by HRTEM EDX that there is a layer of citrate at the periphery of the gold nanoparticles.

Figure 1: 13C CP/MAS NMR spectra of (A) citrate:gold References1. Jean-Marie Basset, Dominique Roberto, Renato Ugo Modern Surface Organometallic Chemistry;

Wiley-VCH Verlag GmbH & Co. KGaA, 2009; Vol. 2. 2. Basset et al. J. Angewandte Chemie International Edition 2005, 44, 6755.

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O-C2-02-03

MOLECULAR OXIDE BASED ELECTRONIC DEVICES

C. Busche1, L. Vilà-Nadal1, J. Yan1, H. N. Miras1, D.-L. Long1, V. P. Georgiev2, A. Asenov2, R. H. Pedersen2, N. Gadegaard2, M. M. Mirza2, D. J. Paul2, J. M. Poblet3, L. Cronin.*1

1WestCHEM, School of Chemistry, The University of Glasgow, Glasgow G12 8QQ, UK2School of Engineering, The University of Glasgow, Glasgow G12 8LT, UK

3Departament de Química Física i Inorgànica, Universitat Rovira i Virgili, c/Marcel·lí Domingo s/n, 43007 Tarragona, Spain


At present, the electronic properties of bulk semiconductors can only be tailored through the irreversible introduction of dopant ions, modifying the electronic structure by either injecting electrons or core holes. By the application of density functional theory (DFT), chemical synthesis, device modelling and nano-device fabrication [1], we were able to design a molecular nano-cluster [2] containing two embedded redox agents that shows different behaviour, depending on the switchable electronic state of the cluster cage or the embedded redox active ion. Construction of two distinct CMOS-based devices demonstrates that not only can the mole-cule based devices act as flash memory, but a two electrode device demonstrates an unprecedented write-once-read-once memory behaviour. Thus, by linking theory, supramolecular design, device level modelling and CMOS fabrication process we have been able fabricate two distinct devices, exploiting the unique properties of the embedded cluster.

Figure 2: SEM image of the nanowire device with a cross sectional TEM images of the nanowire. Sketch and SEM/AFM images of the nanogap electrodes.


C. Busche1, L. Vilà-Nadal1, J. Yan1, H. N. Miras1, D.-L. Long1, V. P. Georgiev2, A. Asenov2,

R. H. Pedersen2, N. Gadegaard2, M. M. Mirza2, D. J. Paul2, J. M. Poblet3, L. Cronin.*1 1WestCHEM, School of Chemistry, The University of Glasgow, Glasgow G12 8QQ, UK

2School of Engineering, The University of Glasgow, Glasgow G12 8LT, UK 3Departament de Química Física i Inorgànica, Universitat Rovira i Virgili, c/Marcel·lí

Domingo s/n, 43007 Tarragona, Spain Presenting author: [email protected]

At present, the electronic properties of bulk semiconductors can only be tailored through the irreversible introduction of dopant ions, modifying the electronic structure by either injecting electrons or core holes. By the application of density functional theory (DFT), chemical synthesis, device modelling and nano-device fabrication [1], we were able to design a molecular nano-cluster [2] containing two embedded redox agents that shows different behaviour, depending on the switchable electronic state of the cluster cage or the embedded redox active ion. Construction of two distinct CMOS-based devices demonstrates that not only can the molecule based devices act as flash memory, but a two electrode device demonstrates an unprecedented write-once-read-once memory behaviour. Thus, by linking theory, supramolecular design, device level modelling and CMOS fabrication process we have been able fabricate two distinct devices, exploiting the unique properties of the embedded cluster.

References: 1. P. A. Lewis, C. E. Inman, F. Maya, J. M. Tour, J. E. Hutchison and P. S. Weiss, J. Am.

Chem. Soc. 127, 17421-17426 (2005). 2. A. Müller, S.Q.N Shah, H. Bögge and M. Schmidtmann, Nature 397, 48-50 (1999).

Figure 1: Linking theory, supramolecular design, device level modelling and CMOS fabrication process to exploit the unique properties of an embedded cluster.

References:1. P. A. Lewis, C. E. Inman, F. Maya, J. M. Tour, J. E. Hutchison and P. S. Weiss, J. Am. Chem. Soc.

127, 17421-17426 (2005).2. A. Müller, S.Q.N Shah, H. Bögge and M. Schmidtmann, Nature 397, 48-50 (1999).

Figure 2: SEM image of the nanowire device with a cross sectional TEM images of the nanowire. Sketch and SEM/AFM images of the nanogap electrodes.


C. Busche1, L. Vilà-Nadal1, J. Yan1, H. N. Miras1, D.-L. Long1, V. P. Georgiev2, A. Asenov2,




At present, the electronic properties of bulk semiconductors can only be tailored through the irreversible introduction of dopant ions, modifying the electronic structure by either injecting electrons or core holes. By the application of density functional theory (DFT), chemical synthesis, device modelling and nano-device fabrication [1], we were able to design a molecular nano-cluster [2] containing two embedded redox agents that shows different behaviour, depending on the switchable electronic state of the cluster cage or the embedded redox active ion. Construction of two distinct CMOS-based devices demonstrates that not only can the molecule based devices act as flash memory, but a two electrode device demonstrates an unprecedented write-once-read-once memory behaviour. Thus, by linking theory, supramolecular design, device level modelling and CMOS fabrication process we have been able fabricate two distinct devices, exploiting the unique properties of the embedded cluster.

References: 1. P. A. Lewis, C. E. Inman, F. Maya, J. M. Tour, J. E. Hutchison and P. S. Weiss, J. Am.

Chem. Soc. 127, 17421-17426 (2005). 2. A. Müller, S.Q.N Shah, H. Bögge and M. Schmidtmann, Nature 397, 48-50 (1999).

Figure 1: Linking theory, supramolecular design, device level modelling and CMOS fabrication process to exploit the unique properties of an embedded cluster.

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Synthesis and Post-Processing of CuInS2 Quantum Dots

Tugce Akdas, Monica Distaso, Wolfgang Peukert

Institute of Particle Technology, Friedrich-Alexander-Universität Erlangen-Nürnberg, Cauerstr. 4, 91058 Erlangen (Germany)

During the last thirty years, quantum dots (QDs) have been widely studied for photovoltaic applications due to their unique opto-electronic properties. More recently, the interest of the scientific community was focused on identifying, producing and applying non-toxic cadmium-free QDs. Among the most promising materials copper based semiconductors (CuO, Cu2-xS, CuInS2/Se2, Cu2ZnSnS4/Se4) have attracted particular attention for their low toxicity. However, while Cu2-xS nanoparticles show low performance in solar cells due to their instability in air,1 CuInS2/Se2 demonstrated remarkable efficiency in functional devices.2 CuInS2 (CIS) has a direct band gap of 1.53 eV and a high absorption coefficient (104-105),3 thus it is an ideal candidate for solar cell applications. Several synthetic strategies have been implemented for the synthesis of CIS QDs, ranging from classical hot injection,4 to one-pot method5 and decomposition of a single-source precursor.6 For high quality QDs, not only the synthesis, but also the post-processing plays an important role. Typically, the post-processing step includes: purification of particles, ligands and/or solvent exchange, film formation and finally incorporation into a working device.In the present contribution, we describe a one-pot synthetic method for the synthesis of CIS QDs with special emphasis on the purification strategies. The synthesis was performed with 1-dodecanethiol as both ligand and sulfur source. In order to obtain QDs with Cu-deficiencies the amount of Cu-precursor was lowered. In the next step, Zn2+ was introduced in the synthesis. The analysis reveals both, the incorporation of Zn2+ into the crystal lattice and the growth of a ZnS shell. This latter step provides an increase of the quantum yields up to 50%. Nuclear Magnetic Resonance (1H-NMR) has been used to identify the chemical nature of the organic ligand shell around the particles. Different purification strategies were tested to properly remove excess organics from the surface, while stability was maintained. The effects of the various purification strategies on the composition and properties of the QDs were investigated.

100 200 300 400 5000

20

40

60

80

100

wei

ght [

%]

temperature [°C]

method w3 method w2 method w1

Figure 1: Thermogravimetric analysis of CuInS2 quantum dots purified with three different procedures.

(Endnotes)1 R. C. Neville Solar Energy Conversion: The Solar Cell, Elsevier, Amsterdam, 1995.2 T. K. Todorov; K. B. Reuter; D. B. Mitzi Adv. Mater. 2010, 22, E156.3 Neumann, H.; Horig, W.; Savelev, V.; Lagzdonis, J.; Schumann, B.; Kuhn, G., Thin Solid Films 1981, 79 (2), 167.4 Allen, P. M.; Bawendi, M. G., J. Amer. Chem. Soc. 2008, 130, 9240.5 Zhong, H.; Zhou, Y.; Ye, M.; He, Y.; Ye, J.; He, C.; Yang, C.; Li, Y., Controlled Chem Mater 2008, 20 (20), 6434.6 Castro, S. L.; Bailey, S. G.; Raffaelle, R. P.; Banger, K. K.; Hepp, A. F., J. Phys. Chem. B 2004, 108 (33), 12429.

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O-C2-02-05

Crystal Growth in Bipyramids: Decahedral Cross Section Revisited

Cansu Zeliha Canbek1, Robinson Cortes Huerto1, Fabienne Testard1, Olivier Spalla1, Jacek Goniakow-ski2, Claudine Noguera2, Simona Moldovan3, Ovidiu Ersen3, Guillaume Wang4, Nicolas Menguy2

1DSM/IRAMIS/SIS2M/LIONS, CEA Saclay, Gif sur Yvette, France2IMPMC, Université Pierre et Marie Curie, CNRS, Paris Cedex 05, France

3Institut de Physique et Chimie des Materiaux de Strasbourg, Strasbourg, France4Laboratoire Matériaux et Phénomènes Quantiques, Université Paris Diderot-Paris 7, Paris Cedex

13, France

In this study we focus on characterization of gold bipyramids from early stages of formation with elec-tron microscopy studies and simulated model analysis. Bipyramids are chosen as a model system due to their unique morphologies and they shed from other anisotropic nanoparticles because of their property to exhibit higher plasmon enhancement than the comparable to other shapes due to their sharp tips.

Our morphological analysis reveals a classical well known decahedron pattern for bipyramid precur-sors whereas for the final particles more complex crystal structures may be observed depending on termination of growth. For that kind of complex analysis, we introduce a simulated model of the par-ticle at different growth stages. Introduction of such mathematical model facilitates the analysis of 2D projected image from 3D particle. Such kind of analysis demonstrates that bipyramids have regular pentagonal cross sections with various twinning faults as the initial precursors. By our method, it is clear to see that small particles conserve their initial twining faults while they start to elongate in par-allel to these stacking faults.

As parallel to crystallographic analysis, we developed a growth model to explain the formation of an-isotropy in such bipyramidal particles as well as pentagonal cross sectioned nanorods. We use HRTEM analysis to explain the crystal growth at different time of reaction.

References

[1] M. Liu, P. Guyot-Sionnest, Journal of Physical Chemistry B, 2005, 109, 22192-22200.[2] J. Burgin, I. Florea, J. Majimel, A. Dobri, O. Ersen, M. Treguer-Delapierre, Nanoscale, 2012, 4, 1299. [3] M. Grzelczak, J. Perez-Juste, P. Mulvaney, L. M. Liz-Marzan, Chemical Society Review, 2008, 37, 1783–1791 | 1783.[4] [5] Z.L. Wang, M.B. Mohamed, S. Link , M.A. El-Sayed, Surface Science, 1999, 440, 809–814[5] Y. Xia, Y. Xiong, B. Lim, S. E. Skrabalak, Angew Chem Int Ed Engl. 2009, 48, 60–103.[6] R. Cortes-Huerto, J. Goniakowski, and C. Noguera, J.Chem. Phys. 138, 244706 (2013)[7] Z.C.Canbek, R. Cortes-Huerto, F.Testard, O.Spalla, J. Goniakowski, C. Noguera N.Menguy, (In prep.)

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O-C2-02-06

THE ENCAPSULATION OF ALKYLATED SILICON QUANTUM DOTS WITHIN INORGANIC-POLYMER COMPOSITE NANOPARTICLES

N.A. Harun1,2, M.J. Benning3, B.R. Horrocks2, D.A. Fulton2 1School of Fundamental Science, Universiti Malaysia Terengganu, 21030, Kuala Terengganu,

Terengganu, Malaysia. 2Chemical Nanoscience Laboratory, School of Chemistry, Newcastle University, Newcastle upon

Tyne, NE1 7RU, UK3School of Mechanical and Systems Engineering, Newcastle University, Newcastle upon Tyne, NE1

7RU, UK.Presenting author: [email protected]

Semiconductor nanocrystals, also known as quantum dots (QDs), have been used extensively as valuable tools for diagnosis, imaging, and optical tracking. QDs offer several outstanding advantages over conventional organic dyes, for instance, a narrow emission spectrum, broad excitation spectrum and large separation between both excitation and emission wavelengths. Furthermore, they show excellent photostability and are often brighter than conventional dyes. The encapsulation of alkylated silicon quantum dots (SiQDs) inside polymer nanoparticles produces composite species which offer the advantages of the luminescence of the SiQDs and the processability of the polymer matrix, increasing the usefulness of SiQDs.

Figure 1: Luminescent enhancement effect of poly(divinylbenzene) composite nanoparticles comprised of silicon quantum dots and gold nanoparticles prepared by miniemulsion polymerization technique.

In this research work, the encapsulation of luminescent SiQDs within polymer nanoparticles has been accomplished. Two-component polymer composite nanoparticles encapsulating both SiQDs and gold nanoparticles (AuNPs) were prepared by a single step miniemulsion polymerization of divinylbenzene.

Luminescence enhancements of up to 15 times were observed from the Au-QDs polymer composite nanoparticles, indicating the luminescence of the SiQDs is enhanced by the proximity of the AuNPs. Miniemulsion polymerization of a monomer mixture of styrene and 4-vinylbenzaldehyde affords polymer nanoparticles presenting reactive aldehyde functional groups on their surfaces allowing the conjugation of molecules through imine, oxime or hydrazone condensation reactions, presenting further scope to modify their properties. We expect that these engineered polymer-encapsulated SiQDs will offer huge potential in numerous applications including new chemical probes of biological processes, and as anti-counterfeiting agents.

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O-C2-02-07

Low oxide, blue luminescent, alkyl functionalized Silicon nanoparticles, with no nitrogen containing surfactant

Jason A. Thomas1, Shane P. Ashby1, Yimin Chao1

1 School of Chemistry, University of East Anglia, Norwich, NR4 7TJ, UKPresenting author: [email protected]

Of ever growing interest in the fields of physical chemistry and materials science, silicon nanoparticles show a great deal of potential. Methods for their synthesis are, however, often hazardous, expensive or otherwise impractical. In our groups previous publications we demonstrated a safe, fast and cheap inverse micelle based method for the production of alkyl functionalized blue luminescent silicon nanoparticles [1], which nonetheless found limitations; due to undesirable Si-alkoxy and remaining S-H functionalization. In the following work these problems are addressed, whereby an optimisation of the reaction mechanism encourages more desirable capping, and the introduction of alcohol is replaced by the use of anhydrous copper (II) chloride. The resulting particles, when compared with their predecessors through a myriad of spectroscopic techniques, are shown to have greatly reduced levels of ‘undesirable’ capping, with a much lower surface oxide level; whilst also maintaining long term air stability, strong photoluminescence and high yields. Luminescence studies show a strong blue luminescence when excited with ultra-violet light. A recent publication by M. Dasog et al. has expressed that this colouration may be attributed to the presence of oxide surface functionality [2], which can only be caused when orange luminescence is quenched by the presence of a nitrogen containing surfactant. This method tests this hypothesis further, and the particles produced by this method are shown to maintain a strong blue photoluminescence despite a reduced surface oxide presence, and no introduction of any nitrogen containing surfactant. This surface elemental analysis is given by both XPS and EDX techniques, and indicates that a more complex system of interactions must be at play, leaving the reasoning behind silicon’s unique Nanoscale luminescence properties once again open for debate.

Figure 1: Optimised inverse micelle SiNP synthesis method quenched through introduction of CuCl2

References1. S. Ashby, J. Thomas, P. Coxon, M. Bilton, R. Brydson, T. Pennycook, and Y. Chao, J. Nanopart. Res.

15, 1425 (2013).2. M. Dasog, Z. Yang, S. Regli, T. M. Atkins, A. Faramus, M. P. Singh, E. Muthuswamy, S. M.

Kauzlarich, R. D. Tilley, and J. G. C. Veinot, ACS NANO 7, 2676 (2013).

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O-C2-03-02

Synthesis and Transport Properties of Functional Oligoyne Molecular Wires

M. Gulcur 1,*, P. Moreno 2, A.S. Batsanov 1, T. Wandlowski 2, M.R. Bryce 1

1 Durham University, Department of Chemistry, South Road, Science Site, Durham, DH1 3LE United Kingdom

2 University of Bern, Freiestrasse 3, CH-3012 Bern, Switzerland* Current Address: University of Leeds, School of Chemistry, Woodhouse Lane, Leeds, LS2 9JT, United Kingdom


Conjugated polyyne molecules comprise an array of sp-hybridized carbon atoms with alternating single and triple bonds and almost cylindrical electron delocalization in a one-dimensional chain. Polyynes and shorter sp oligomers (oligoynes) have been proposed for molecular electronics applications (wires, switches, non-linear optics, etc.) [1]. Theoretical studies have predicted that polyynes should have excellent intramolecular electron- and charge-transport properties, exhibiting efficient molecular wire behavior [2]. A standard protocol for accurately assessing the charge transport through single or a few molecules is to anchor the molecule(s) between metal electrodes (often gold) and to study the electronic properties of the metal-molecule-metal junction by scanning tunneling microscopy (STM) or mechanically controllable break junction (MCBJ) techniques [3].

Ar Ar

Ar = H2N NC HS S

Ar Ar Ar Ar

n = 1 n =

2 n = 4

N

Py SH*

Ar-1 Ar-2 Ar-4

* SH-1, SH-2

and SH-4

were isolated

as thioacetate

NH2 CN DHBT

Figure 1: Diaryloligoyne oligoyne compounds (n= 1, 2, 4) with functionalized end-groups.

In this study, we synthesized series of diaryl oligoyne compounds (Fig. 1) with functionalized end-groups and studied their single molecule electron transport properties by using STM-Break Junction and MCBJ techniques [4]. The results show that oligoynes are excellent candidates for molecular wires since the conductance is weakly dependant to the length of the molecule.

References1. [a] A. D. Slepkov et. al, J. Chem. Phys. 2004, 120, 6807. [b] J. Cornil, et. al, Adv. Mater. 2001, 13,

1053.2. Ž. Crljen, G. Baranović, Phys. Rev. Lett. 2007, 98, 116801.3. W. Hong et al. J. Amer. Chem. Soc., 2012, 134, 2292.4. [a] M. Gulcur et.al. Chem. Eur. J. 2014, 20, 4653. [b] P. Moreno, M.Gulcur et al. J. Amer. Chem.

Soc., 2013, 135, 12228.

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O-C2-03-03

TOWARDS ELECTROACTIVE GRAPHENE BY CHEMICAL MODIFICATION

L. Rodriguez-Perez1, M. Garrido1, A. Ferrer, A. Muñoz1, B. M. Illescas, M. A. Herranz1 and N. Martin1,2

1Organic Molecular Materials Group, Organic Chemistry Department, Complutense University of Madrid, 28040, Spain

2IMDEA Nanoscience, Cantoblanco Campus, 28049 Madrid, Spain Presenting author: [email protected]

The one atom thick layer sheet of graphite -known as graphene- is playing a major role in today’s science and technology due to its outstanding mechanical and electronic properties. The versatility of this carbon honeycomb allows their integration in electron-donor-acceptor structures and, has evolved into a promising platform for novel optoelectronic devices.1

However, one mayor drawback of this 2D material is the low solubility and re-aggregation found in solution processes. To overcome this problem, the chemical modification, by covalent or supramolecular methods, has reveal as an efficient methodology to harvest the full potential of graphene and to facilitate its processing and transfer to solid substrates.2 In particular, the paradigm is shifting towards optimizing the non-covalent interactions since they assist in the stabilization of graphene layers without interfering on the eletronic properties. In contrast, the covalent modification of graphene can alter its inherent properties if it is not controlled, although the robustness of the covalent nanoconjugates make them also suitable for practical applications.

In this communication, we will present our results on different suppramolecular and covalent approaches towards the formation of nanohybrids based on graphene and different electron-donor molecules with the aim of tuning/altering the electronic features of graphene. The detailed characterization of the new chemical nanostructures will be thoroughly discussed.

(Endnotes)1 K. Dirian, M. A. Herranz, G. Katsukis, J. Malig, L. Rodríguez-Pérez, C. Romero-Nieto, V. Strauss, N. Martín and D. M. Guldi, Chem. Sci., 4, 4335, (2013).2 L. Rodríguez-Pérez, M. A. Herranz and N. Martín, Chem. Commun.49, 3721, (2013).

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O-C2-03-04

Selective Solid-Phase Fullerene Encapsulation and Liberation using a Sponge-like molecular cage

C. García-Simón,1 M. Garcia-Borràs,1 L. Gómez,1 Teodor Parella,2 S. Osuna,2 M. Swart,1 J.M. Luis,1 I. Imaz,4 D. Maspoch,4 M. Costas,1 and X. Ribas1

1Institut de Química Computacional i Catàlisi, Departament de Química, Universitat de Girona, E17071, Girona, Catalonia, Spain

2Servei de RMN, Facultat de Ciències, Universitat Autònoma de Barcelona (UAB), Campus UAB, E-08193 Bellaterra Catalonia, Spain

3CIN2(ICN-CSIC), Catalan Institute of Nanotechnology, Esfera UAB, 08193 Bellaterra, Catalonia, Spain


Since fullerenes are available at macroscopic quantities from fullerene soot, large efforts have been geared toward designing an efficient strategy to obtain highly pure fullerenes, which are subsequently applied in multiple research fields.[1] Multitudes of cage-like platforms have been designed to target the encapsulation of fullerenes in solution, through specific host-guest interactions.[2] In this work we pres-ent a supramolecular metallo-cage capable of encapsulating fullerenes from C60 to C84, instantaneously and at room temperature. The fullerenes adducts have been fully caracterized by NMR, HRMS and UV-Vis. For C60 and C70 adducts, synchrotron XRD data has been obtained. Interestingly, the cage-fullerene interaction can also occur in the solid state, just by soaking a crystalline sample of the nanocage into a solution of fullerenes in toluene.[3] Finally, we have designed a washing-based strategy which allows us to obtain hihgly pure C60 from solid samples of cage charged with a mixture of fullerenes. The solid-phase fullerene encapsulation and liberation represents a novel twist in host-guest chemistry for molecular nanocage structures.

+ r.t

Tol/MeCN9/1

Solvent

washing

Cn Fullerene Cn Fullerene

References1. M.D. Tzirakis, M. Orfanopoulos, Chem. Rev., 133, 5262-5321 (2013).2. D. Canevet, E.M. Pérez, N. Martín, Angew. Chem, Int. Ed., 20, 2-14 (2011).3. Y. Ionomuka, T. Arai, M. Fujita, Nat. Chem, 2, 780-783 (2010).

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O-C2-03-05

Study of surface modification of silver nanoparticles by cysteine and its substitution derivatives

P. Řezanka1, H. Ryšavá1, J. Koktan1, P. Matějka2

1Institute of Chemical Technology Prague, Department of Analytical Chemistry, Technická 5, 166 28 Prague 6, Czech Republic

2Institute of Chemical Technology Prague, Department of Physical Chemistry, Technická 5, 166 28 Prague 6, Czech Republic


In the first part of this work the system containing silver nanoparticles (~45 nm [1] and ~20 nm) and L-cysteine at the concentration range from 10-9 to 10-2 mol/L was studied by absorption and electronic circular dichroism spectroscopy in the UV-Vis range and surface enhanced Raman spectroscopy at different pH and ionic strength. By later one the presence of L-cysteine was clearly detectable even at 10-9 mol/L. The analysis of circular dichroism spectra by statistical methods, namely two-step cluster analysis, principal component analysis, and partial least square regression [2], allowed determination of L-cysteine in the range from 10-5 to 10-3 mol/L [3]. Moreover this system is very sensitive to addition of D-cysteine; hence, the enantiomeric ratio can be estimated and the presence of D-cysteine in the system is clearly detectable even at 10-6 mol/L, i.e. the content of this enantiomer is as low as 2 % in the mixture.

In the second part the influence of cysteine derivatives on the spectral behavior of silver nanoparticles was studied. It was found that in the presence of cysteine substitution derivatives there are no ECD signals. Hence the amount of molecules immobilized on the nanoparticles surface was determined. The results showed that the amount of cysteine immobilized on the nanoparticles surface is about one magnitude higher than the amount of cysteine substitution derivatives. Thus for formation of ECD signal of nanoparticles several layers of chiral molecules have to be immobilized on nanoparticles surface.

AcknowledgementsThis work was supported by the project no. P206/12/P026 of the Czech Science Foundation and by specific university research (MSMT No 20/2014).

References

1. Pavel Řezanka, Kamil Záruba, Vladimír Král, Colloids Surf. A, 374, 77-83 (2011).2. Pavel Řezanka, Hana Řezanková, Pavel Matějka, and Vladimír Král, Colloids Surf. A 364, 94-98

(2010).3. Pavel Řezanka, Jakub Koktan, Hana Řezanková, Pavel Matějka, Vladimír Král, Colloids Surf. A,

436, 961-966 (2013).

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O-C2-03-06

THIOLATE-PROTECTED GOLD CLUSTERS: STRUCTURE, CHIRALITY AND PROPERTIES OF THE GOLD – SULFUR INTERFACE

T. Bürgi1

1University of Geneva, Department of Physical Chemistry, 30 Quai Ernest-Ansermet, 1211 Geneva 4, Switzerland


Monolayer protected gold nanoparticles and clusters have promising potential applications as building blocks for nanotechnology, as catalysts or as sensors. Very recently, the chirality of these materials has attracted the attention of researchers [1] and application to chiral technologies is an interesting perspective. This contribution deals with the preparation of chiral gold nanoparticles, with their chiroptical properties and with exchange reactions in their ligand shell. We applied Electronic and Vibrational Circular Dichroism (ECD/VCD) to study electronic transitions that are mainly located in the cluster core and to perform conformational analysis of the molecules in the ligand shell [2]. Ligand exchange reactions were performed and monitored by ECD and mass spectrometry [3].The chiroptical studies indicate that chirality can be bestowed to gold clusters through the adsorption of chiral thiolates. However, even with achiral ligands chiral clusters can be obtained. In this case a racemic mixture is obtained during the synthesis. Using chromatography we were able to separate the enantiomers of Au38 [4] and Au40 clusters. With the separated enantiomers at hand it was possible to study the properties of the gold – thiolate interface in detail. The engineering of the latter with molecular precision is an important prerequisite for future applications of thiolate-protected particles and clusters. A key question in this respect concerns the flexibility of the gold – sulfur interface. We could demonstrate racemization of the chiral cluster, which goes along with a drastic rearrangement of its surface involving place exchange of several thiolates. This racemization takes place at modest temperatures (40 – 80 °C) without significant decomposition. The experimentally determined activation energy indicates that the rearrangement goes along without complete Au – S bond breaking. Introduction of a single dithiol into the cluster shell leads to a drastic loss of its flexibility and much higher racemization temperatures. These changes are also reflected in the low – energy Au – S vibrations. Furthermore, using chromatography we isolated species with exactly one ligand exchanged but differing in the positions of the exchange [5]. The ligand can move to different symmetry-unique sites at moderate temperatures.

References[1] T. G. Schaaff, G. Knight, M. N. Shafigullin, R. F. Borkman and R. L. Whetten, J. Phys. Chem. B 102, 10643 (2009). [2] C. Gautier, and T. Bürgi, ChemPhysChem 10, 483 (2009).[3] S. Knoppe, A. C. Dharmaratne, E. Schreiner, A. Dass and T. Bürgi, J. Am. Chem. Soc. 132, 16783 (2010).[4] I. Dolamic, S. Knoppe and T. Bürgi, Nature Commun. 3, 798, (2012).[5] L. Beqa, D. Deschaps, S. Perrio, A.-C. Gaumont, S. Knoppe and T. Bürgi, J. Phys. Chem. C 117, 21619 (2013).

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O-C3-01-02

Supramolecular self-assembled yoctowell cavities for controlled release of drug molecules

S. V. Bhosale1

1School of Applied Sciences, RMIT University, GPO BOX 2476, Melbourne, VIC-3001, Australia Presenting author: [email protected]

Drug delivery systems which medically transport active molecules to diseased cells, in a controlled manner, have gained much attention in recent years. Yoctowells with various kinds of walls can be constructed precisely through a range of techniques depending upon the walls of the wells employed.[1] Their unique, rigid and hydrophobic surfaces have endowed yoctowells with outstanding abilities to selectively bind various types of guests. Yoctowell (1yL= 8 nm3 i.e. 10-24 L volume) cavities on magnetic silica nanoparticles were used for the encapsulation and release of the drug molecule, Doxorubicin (DOX)[2] and “mitoxantrone (MTZ)”[3] using naturally-occurring stimuli i.e. pH. Firstly, DOX or MTZ was encapsulated from a bulk solution at physiological, and then released from the yoctowells, in a controlled manner, by manipulating the pH (7.2-3.0). The sustained release of DOX and MTZ, and the recovery of active yoctowells after the release process, provides potential for development of a new generation of drug-delivery system for real, practical application.

Figure 1: Illustration of a porphyrin based yoctowell system for the encapsulation and release of drug molecules.

References1. S. V. Bhosale, S. J. Langford, Chem. Soc. Rev., 41, 1637 (2012). 2. S. V. Bhosale, S. V. Bhosale, Sci. Rep. 2013, 3: 1982 | DOI: 10.1038/srep01982.3. S. V. Bhosale, Submitted for publication.

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O-C3-01-03

CONTROLLED REVERSIBLE ENCAPSULATION WITHIN REDOX-RESPONSIVE SELF-ASSEMBLED CAGES

V. Croué, S. Goeb, S. Bivaud, M. Allain, M. Sallé

University of Angers – CNRS 6200, Laboratoire MOLTECH-Anjou, 2 bd Lavoisier, 49045 Angers, France

[email protected]

The coordination-driven self-assembly strategy has allowed the access to a wide variety of molecular rings and cages for the last decade. In some cases, the corresponding resulting host cavities exhibit guest inclusion properties, offering fascinating perspectives for various research topics, such as drug delivery, guest sensing or catalysis [1]. It is worth noting that only few of these structures present redox properties, and most of the described redox-active assemblies are electro-deficient. On this ground, we have been interested in constructing electronically complementary electron-rich self-assembled rings/cages. The latter incorporate highly p-donating and S-rich frameworks based on tetrathiafulvalene (TTF) [2], bis(pyrrolo)TTF [3] and also extended-TTF [4] (exTTF, Figure 1a).

In this communication, we describe our efforts in preparing metalla-rings/cages from exTTF-based ligands. This unique redox-active system presents fascinating structural and electronic properties [5] that we have explored in new discrete metalla-assemblies, which vary by the size and by the solubility. The binding ability of these new containers for various guests as well as their ability to redox-control the host-guest association constant, are depicted.

Figure 1: a) exTTF, b) an exTTF-based self-assembled cage and c) its X-ray structure (synchrotron).

References1. (a) M. Han, D. M. Engelhard and G. H. Clever, Chem. Soc. Rev. 43, 1848-60 (2014); (b) H. Amouri, C. Desmarets and J. Moussa, Chem. Rev. 112, 2015-41 (2012); (c) R. Chakrabarty, P. S. Mukherjee and P. J. Stang, Chem. Rev. 111, 6810-918 (2011).2. V. Vajpayee, S. Bivaud, S. Goeb, V. Croué, M. Allain, B. V. Popp, A. Garci, B. Therrien and M. Sallé, Organometallics 33, 1651-58 (2014).3. S. Bivaud, J. Y. Balandier, M. Chas, M. Allain, S. Goeb and M. Sallé, J. Am. Chem. Soc. 134, 11968-70 (2012).4. S. Bivaud, S. Goeb, V. Croué, P. I. Dron, M. Allain and M. Sallé. J. Am. Chem. Soc. 135, 10018-21 (2013).5. F. G. Brunetti, J. L. Lopez, C. Atienza and N. Martín, J. Mater. Chem. 22, 4188-205 (2012).

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O-C3-01-04

Molecular Wire Behavior in Donor-Fullerene Dyads

B. M. Illescas, Valentina Sacchetti, N. Martín.

Departamento de Química orgánica, Facultad de Química, Universidad Complutense, 28040, Madrid, Spain


Organic photovoltaic and molecular electronic applications require the study of the efficiency and rates of charge transport in artificial photosynthetic mimics. Donor-bridge-acceptor (DBA) systems are considered as model systems for the study and fine-tuning of light-induced charge-separation and charge-recombination processes. In these systems, an electron donor moiety is connected to an electron acceptor though a spacer, generally a π-conjugated oligomer, which enables the electronic coupling between the termini. In our group, we have developed a systematic study of the charge transfer processes in exTTF-C60 dyads, varying the nature and length of the wire connecting these electroactive moieties.1

In order to gain control on the charge-separated state lifetimes, it is important to introduce a dynamic bridge with two electronically different forms which can be interconverted by an external stimulus (Figure 1). With this in mind, photoswitchable dithienylethenes (DTEs) were introduced in DBA systems based on exTTF and C60. DTEs reversibly interconvert between the ring-open and ring-closed forms, allowing the control on the electronic communication between the donor and the acceptor units.

Figure 1: Schematic representation of the exTTF-DTE-C60 systems and their interconversion between the decoupled ring-open form (blue) and the ring-closed form (red).

References

1. D. M. Guldi, B. M. Illescas, C. M. Atienza, M. Wielopolski, N. Martín, Chem. Soc. Rev. 38, 1587 (2009).

2. M. Wielopolski, J. Santos, B. M. Illescas, A. Ortiz, B. Insuasty, T. Bauer, T. Clark, D. M. Guldi, N. Martín, Energy & Env. Sci. 4, 765 (2011).

3. M. Wielopolski, A.Molina-Ontoria, C. Schubert, J. T. Margraf, E. Krokos, J. Kirschner, A. Gouloumis, T. Clark, D. M. Guldi, N. Martín, J. Am. Chem. Soc. 135, 10372 (2013).

4. S. Castellanos, A. Vieira, B. M. Illescas, V. Sacchetti, C. Schubert, J. Moreno, D. M. Guldi, S. Hecht, N. Martín, Angew. Chem. Int. Ed. 52, 13985 (2013).

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O-C3-01-05

EXPLOITING THE NON-COVALENT INTERACTIONS OF FULLERENE WITH THE GRAPHITIC STEP-EDGES OF CARBON NANOREACTORS AS A MECHANISM FOR HETEROGENISATION OF MOLECULAR CATALYSTS

M.A. Lebedeva, T.W. Chamberlain, M. Schröder and A.N. Khlobystov

School of Chemistry, University of Nottingham, NG7 2RD, Nottingham, UKPresenting author: [email protected]

The ability to separate and recycle the metal catalyst from reaction mixtures without excessive purification steps is crucial for sustainable transition-metal based catalysis. Recyclability of catalysts can be enhanced by heterogenisation of the catalyst molecules, achieved by immobilisation on solid supports using covalent or non-covalent bonding between the catalyst molecules and the support material. Whilst covalent functionalization is synthetically demanding, non-covalent immobilisation can be achieved easier, and results in the formation of materials in which the structure and the intrinsic properties of the molecular catalyst are retained. However non-covalent interactions are usually reversible resulting in the gradual loss of the catalytic activity upon recycling, and, furthermore, often lower the degree of control over the location of the catalyst molecules on the support. Utilisation of a good anchoring group is required, which can site-specifically bind to the solid support surface and achieve high stability of the resulting heterogeneous material.Carbon nanostructures such as carbon nanotubes (CNT) and graphite have been used extensively as robust supporting materials for immobilisation of catalysts on both internal and external surfaces and provide excellent stability, thermal and electric conductivity. Extended conjugated systems of sp2-carbons of CNT and graphite allow catalyst molecules tagged with polyaromatic hydrocarbons such as pyrene to be anchored to the surface using π-π stacking interactions.[1] However such anchoring is relatively weak, and is not site specific with catalyst molecules deposited randomly over the smooth carbon surfaces. In this study we report a new methodology for heterogenisation of transition metal catalysts by tagging them with a fullerene group which allows reliable and site-specific anchoring inside graphitised carbon nanofibre (GNF) nanoreactors due to strong van der Waals interactions between the fullerene cage and the internal graphitic step-edges of GNFs. The spherical shape and large π-electrons system of the functionalised C60 fullerene is known to have a high affinity for sp2-hybridised carbon structures and is a perfect match for the graphitic step-edges binding preferentially to the step-edge compared to the flat terrace of the inner surface of the GNF supports. Herein we demonstrate that the non-covalent immobilisation of the fullerene-tagged copper salen catalyst[2] inside GNF nanoreactors can be used to form well-defined heterogeneous catalysts with molecules located in a very distinct, confined environment. These heterogeneous catalysts exhibit enhanced stability and recyclability whilst retaining the activity and selectivity of the individual catalytic centres.

References1. C. Vriamont, M. Devillers, O. Riant and S. Hermans, Chem. Eur. J., 2013, 19, 12009-12017.2. M. Lebedeva, T. Chamberlain, E. S. Davies, D. Mancel, B. Thomas, M. Suyetin, E. Bichoutskaia, M.

Schröder and A. Khlobystov, Chem. Eur. J., 2013, 19, 11999-12008.

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O-C3-01-06

a,w-BIS(TPY)OLIGOTHIOPHENES AND THEIR METALLO-SUPRAMOLECULAR POLYMERS – SYNTHESIS AND PROPERTIES

J. Svoboda, P. Bláhová, T. Vitvarová, J. Zedník, J. Vohlídal

Department of Physical and Macromolecular Chemistry, Charles University in Prague, Faculty of Science, Hlavova 2030, CZ-128 40, Prague 2, Czech Republic 1Affiliation one, Presenting author:

[email protected]

Reversible linking of a,w-functionalized oligomer molecules by non-covalent interactions or appropriately labile covalent or coordination bonds gives a constitutional-dynamic polymer called dynamer (Scheme 1). The main advantage of dynamers is possibility of their post-synthesis modification allowing tuning or tailoring their properties or self-healing of their chains by exchanges or reshufflings their components. An ideal dynamer can be repeatedly switched between polymeric and oligomeric state in contrast to polymers composed of “permanent” macromolecules.

SN N

N

N

N

N

Mt2+

SN N

N

N

N

N

nS NN

N

N

N

N

Mt2+

R R

R

m

m

m + 1

n n

Scheme 1: Formation of metallo-supramolecular polymers.

In this contribution we present new results concerning preparation of the metallo-supramolecular polymers from oligothiophenes with 2,2':6',2''-terpyridine (tpy) end-groups and Zn2+, Fe2+, La3+ and Eu3+ ion couplers, their optical properties, effect of metal and oligothiophene used, SEC and viscosimetry study. The results include the complexation of 4'-thiophene-3-yl-tpy for a comparison.

Figure 1: Changes in UV/vis (A, C) and photoluminescence (B, D) spectra accompanied titration of ligand with Zn2+ (A, B) and Fe2+ (C, D).

References1. T. Vitvarová, J. Zedník, M. Bláha, J. Vohlídal and J. Svoboda, Eur. J. Inorg. Chem. 3866 (2012).2. J. Svoboda, P. Štenclová, F. Uhlík, J. Zedník and J. Vohlídal, Tetrahedron 67, 75 (2011).3. P. Bláhová, J. Zedník, I. Šloufová, J. Vohlídal and J. Svoboda Soft Mater. 12, 214 (2014).

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O-C3-01-07

Development of Bacterial Cellulose based Materials for Polymer Electrolyte Fuel Cells

C. Vilela1, T.D.O. Gadim2, F.M.L. Figueiredo2, A.J.D. Silvestre1, C.S.R. Freire1.1CICECO and Department of Chemistry, University of Aveiro, 3810-193 Aveiro, Portugal

2CICECO and Department of Materials and Ceramic Engineering, University of Aveiro, 3810-193 Aveiro, Portugal


The growing need to reduce pollution levels and greenhouse gases is leading to major efforts on the development of new energy sources and more efficient, environmentally sustainable energy conversion technologies. Hydrogen and fuel cells are at the center of this new paradigm. In particular, the polymer electrolyte membrane fuel cell (PEMFC) technology is considered a first priority for the road vehicle drive chain, and perhaps for rail use [1].The present study reports the development of a new generation of bio-based nanocomposite proton exchange membranes based on functionalized bacterial cellulose (BC) membranes with protogenic groups, produced by the in situ free radical polymerization of monomers with proton donator groups within the swollen BC network.The first investigated system deals with a nanostructured composite electrolyte consisting of a BC network and a cross-linked poly(4-styrene sulfonic acid) (PSSA) polyelectrolyte [2]. The results showed that the BC nanofibrilar network endows the composite membranes with excellent mechanical properties and the sulfonic acid groups in PSSA are responsible for their high ionic exchange capacity. This combination of electric and viscoelastic properties with low cost underlines the potential of these nanocomposites as a bio-based alternative to other polymer membranes for application in fuel cells, or other devices requiring functional proton conducting elements.Another investigated system concerns the induction of proton conductivity by the in situ polymerization of 2-hydroxyethyl methacrylate phosphate (HEMAP) inside the BC network. The obtained nanocomposite membranes exhibited higher thermal stability and mechanical performance than the pristine polymer P(HEMAP). Moreover, preliminary conductivity tests also envisage their use as a new generation of low-cost and environmentally sustainable membranes for polymer electrolyte fuel cells.

References1. Council of the European Union, Council Regulation Setting up the Fuel Cells and Hydrogen Joint

Undertaking Multi-Annual Implementation Plan 2008-2013; 8541/08 (2008).2. T. D. O. Gadim, A. G. P. R. Figueiredo, N. C. Rosero-Navarro, C. Vilela, J. A. F. Gamelas, A. Barros-

Timmons, C. P. Neto, A. J. D. Silvestre, C. S. R. Freire, and F. M. L. Figueiredo, ACS Appl. Mater. Interfaces (2014), DOI: 10.1021/am501191t.

Acknowledgments: The authors wish to thank the Portuguese Foundation for Science and Technology (FCT) for the postdoctoral grant to C. Vilela (SFRH/BPD/84168/2012), the research project CelFuelCel- EXPL/CTM-ENE/0548/2012 and for Associate Laboratory CICECO funding (PEst-C/CTM/LA0011/2013). C.S.R. Freire acknowledges FCT/MCTES for a research contract under Investigador FCT 2012, and F.M.L. Figueiredo for the Investigador FCT 2013 contract number IF/01174/2013.

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O-C3-02-02

Polariser free optically activated shutter

M. M. Qasima, S. M. Morrisb, S. Nosheena and T. D. Wilkinsona.aDepartment of Engineering, Centre of Molecular Materials for Photonics and Electronics,

University of Cambridge, 9 JJ Thomson Avenue, Cambridge CB3 0FA, United Kingdomb Department of Engineering Science, University of Oxford, Parks Road, Oxford, OX1 3PJ

Since 1980’s a lot of interest has been drawn to devise optical filters based on cholesteric phase for instance, notch filter,1–3 colour reflector,4,5 and light shutter 6–8. All of these devices utilised the unique feature of chiral nematic liquid crystals which is the well-known selective reflection band. One of the benefits of using chiral nematic LCs is that the reflection band can be “tuned” by subjecting the LC to a range of external stimuli. An active area of research is to use light to control the reflection band by using molecular structures that contain a photo-active element. This is advantageous as it offers a means of controlling the structure remotely and is particularly attractive as an optical shutter component for sensor devices. One limitation, however, is that the reflection band only exists for one handedness of circularly polarized light. Here we present a polariser free optically activated shutter based upon a short-pitch chiral nematic liquid crystal device. This device can be optically tuned as a full reflection band from 400nm to 900 nm. The LC mixture is comprised of photo-active chiral dopants, in the trans-state this device appears as a slightly yellowish in colour due to the chromophore of this photo-active component. However, as the pitch varies through exposure of visible or UV light exposure, the device becomes reflective reaching a maximum for a particular value of the pitch. As a result, it is possible to switch the device from blue to selective reflection states remotely.

(a) (b)Figure: Reversible tuning of the reflection band of the photo-responsive chiral nematic LC

mixture, a) the transmission spectra showing a red-shift of the reflection band when illuminated with UV light for a period of 35 s and a power density of 5 mW/cm2 and b) The transmission spectra showing a blue-shift of the reflection band when illuminated with visible light (625 nm) with a power density of <1 mW/cm2.

References1 H. J. Masterson, G. D. Sharp, and K. M. Johnson, Opt. Lett. 14, 1249 (1989).2 G. D. Sharp, K. M. Johnson, and D. Doroski, Opt. Lett. 15, 523 (1990).3 M. Mitov, E. Nouvet, and N. Dessaud, Eur. Phys. J. E 15, 413 (2004).4 R. A. M. Hikmet and H. Kemperman, Nature 392, 476 (1998).4 S. S. Choi, S. M. Morris, W. T. S. Huck, and H. J. Coles, Adv. Mater. 21, 3915 (2009).6 D. K. Yang, L. C. Chien, and J. W. Doane, Appl. Phys. Lett. 60, 3102 (1992).

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O-C3-02-03

FUSED GLYCOLURIL-TETRATHIAFULVALENE MOLECULAR CLIPS:RECOGNITION OF ELECTRODEFICIENTS GUESTS

Y. Cotelle1, S. Legoupy1, P. Hudhomme.1

1 Université d’Angers, MOLTECH-Anjou, UMR 6200, Angers, FrancePresenting author: [email protected]

Recognition of cations and anions by molecular clips and tweezers have been extensively investigated, whereas the specific recognition of neutral guests still remains a difficult challenge1 due to the weak interactions available in such host-guest system. To achieve this goal, we have focused our attention on the synthesis of molecular clips functionalized by two sidewalls with electron donating properties for enhancing the recognition ability of electron deficient guests. Tetrathiafulvalene (TTF) derivatives are well-known for their electron-donating properties thanks to three oxidation states (neutral, radical cationic and dicationic species) , which make them good candidates for the recognition of neutral electron deficient guests through weak donor-acceptor interactions. Moreover, glycolurils are recognized to afford rigid structures allowing strong interactions between host and planar guest.

Figure 1: Synthesis and recognition of fused glycoluril-tetrathiafulvalene molecular clip.

We will describe the synthesis of molecular clips built from a glycoluril spacer and bearing TTFs arms.2 The studies of their recognitions abilities in solution for different neutral guests will be presented.

References1. Hardouin-Lerouge M., Hudhomme P., Sallé M., Chem. Soc. Rev., 2011, 40, 30-43.2. Cotelle Y., Allain M., Legoupy S., Hudhomme P., Org. Lett., 2014, DOI :10.1021/ol500458e

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O-C3-02-04

Porous Coordination Polymers based on (bi)pyridinium Ligands

O. Toma1, N. Mercier1, M-C. Dul1, C. Botta2.1Laboratoire MOLTECH-Anjou, 2 Bd Lavoisier, 49045 Angers, France

2Insituto per lo Studio delle Macromolecole, CNR, via Bassini 15, 20133 Milano, ItalyPresenting author: [email protected]

In the broad field of Porous Coordination Polymers (PCPs) which are crystalline materials with high potentiality in the field of gas storage (H2, CH4, CO2,…), chemical sensors or drug delivery, the presence of cationic sites in the structures of PCPs is expected to increase the sorption abilities [1]. Recently we started to explore system including N-substituted-4,4’-bipirydinium monocation bearing carboxylate group (bp4mc), 1,4-benzenedicarboxylate (bdc2-), which has given the interesting porous material (Zn2(bp4mc)(bdc)2)2DMF·H2O, already mentioned [2]. We discovered also others phases, and the one of the most interesting is [Zn5(bp4mc)2(bdc)4(HCO2)]guest, which contains the formate anion resulting from the hydrolysis of a solvent DMF. A 3D network with large pores is defined (Figure 1.a), but the whole structure results from the interpenetration of networks, and the materials is slightly porous of 15%. Interestingly, this PCP has photochromic properties. As well known, this property results from a photo-induced electron transfer from a donor to the electron acceptor pyridinium cycle [3]. The electron donor entity could be either (bdc) through the benzene ring (benzene ring and pyridinium cycles are faced in the structure), either carboxylate group of bp4mc, or guest molecules. Anyway, interestingly, the photochromic properties could be changed or modulated depending on the analyte guest included in pores. In the Cd2+/bdc2-/bp4mc system, a new interesting porous compound is obtained: [Cd2(bp4mc)(bdc)2DMF]guest. Here again, an interpenetration of two 3D networks occurs. Nevertheless, the structure shows clear 1D channels (Figure 1.b) with voids estimated to 45% of the whole volume.

Figure 1: a- [Zn5(bp4mc)2(bdc)4(HCO2)]guest, view of one 3D network (up), photos of crystals showing photochromic behavior; b- space filling representation of the PCP [Cd2(bp4mc)(bdc)2DMF]guest.

References1. Special issue Metal Organic Frameworks: Chem. Soc. Rev. 112, 673-1268 (2012).2. S. Kitagawa et al J. Am. Chem. Soc. 131, 10336 (2009), Inorg. Chem. 15, 10735 (2013).3. (a) N. Leblanc, N. Mercier et al Inorg. Chem. 49, 5824 (2010); (b) O. Toma, N. Mercier, Eur. J. Inorg.Chem. 1113 (2013).

Porous Coordination Polymers based on (bi)pyridinium Ligands

O. Toma1, N. Mercier1, M-C. Dul1, C. Botta2. 1Laboratoire MOLTECH-Anjou, 2 Bd Lavoisier, 49045 Angers, France

2Insituto per lo Studio delle Macromolecole, CNR, via Bassini 15, 20133 Milano, Italy Presenting author: [email protected]

In the broad field of Porous Coordination Polymers (PCPs) which are crystalline materials with high potentiality in the field of gas storage (H2, CH4, CO2,…), chemical sensors or drug delivery, the presence of cationic sites in the structures of PCPs is expected to increase the sorption abilities [1]. Recently we started to explore system including N-substituted-4,4’-bipirydinium monocation bearing carboxylate group (bp4mc), 1,4-benzenedicarboxylate (bdc2-), which has given the interesting porous material (Zn2(bp4mc)(bdc)2)2DMF·H2O, already mentioned [2]. We discovered also others phases, and the one of the most interesting is [Zn5(bp4mc)2(bdc)4(HCO2)]guest, which contains the formate anion resulting from the hydrolysis of a solvent DMF. A 3D network with large pores is defined (Figure 1.a), but the whole structure results from the interpenetration of networks, and the materials is slightly porous of 15%. Interestingly, this PCP has photochromic properties. As well known, this property results from a photo-induced electron transfer from a donor to the electron acceptor pyridinium cycle [3]. The electron donor entity could be either (bdc) through the benzene ring (benzene ring and pyridinium cycles are faced in the structure), either carboxylate group of bp4mc, or guest molecules. Anyway, interestingly, the photochromic properties could be changed or modulated depending on the analyte guest included in pores. In the Cd2+/bdc2-/bp4mc system, a new interesting porous compound is obtained: [Cd2(bp4mc)(bdc)2DMF]guest. Here again, an interpenetration of two 3D networks occurs. Nevertheless, the structure shows clear 1D channels (Figure 1.b) with voids estimated to 45% of the whole volume.

a b Figure 1: a- [Zn5(bp4mc)2(bdc)4(HCO2)]guest, view of one 3D network (up), photos of crystals showing photochromic behavior; b- space filling representation of the PCP [Cd2(bp4mc)(bdc)2DMF]guest. References 1. Special issue Metal Organic Frameworks: Chem. Soc. Rev. 112, 673-1268 (2012). 2. S. Kitagawa et al J. Am. Chem. Soc. 131, 10336 (2009), Inorg. Chem. 15, 10735 (2013). 3. (a) N. Leblanc, N. Mercier et al Inorg. Chem. 49, 5824 (2010); (b) O. Toma, N. Mercier, Eur. J. Inorg.Chem. 1113 (2013).

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O-C3-02-05

Novel Tetravalent Silicon Linkers in Metal Organic Framework (MOF) Construction

R. P Davies1, P. D. Lickiss1, I. Timokhin1

1 Department of Chemistry, Imperial College London, SW7 2AZ, London, UKPresenting author: [email protected]

The field of metal-organic frameworks has grown exponentially over the past decade, with materials reported with extremely high porosities and potential applications in areas as diverse as gas storage, gas separation, catalysis and drug delivery. The design of the organic connector plays a key role in the design of new MOF materials and the modification of existing ones. However, despite recent advances the preparation of rigid tetrahedral organic-connectors for MOF building remains somewhat problematic due to the challenging syntheses of these ligands. We have sought to address this by pioneering the use of silicon as a tetrahedral centre, which can be readily substituted to form tetrahedral and other rigid and highly branched linkers.[1] A range of highly branched organic connecting ligands based on one or more silicon centers with up to eight pendant aryl-carboxylate groups has been prepared.[2] These new silicon-based compounds are all robust, and can crucially be prepared in large quantities and high purity with relative ease. This contrasts markedly with their carbon analogues, which either involve long and low yielding syntheses or are inaccessible. A number of new MOF materials based on these ligands will be presented including a series of related MOFs built from the rigid tetrahedral H4ttps ligand with Mn(II), Cu(II) or Cd(II) metal based nodes exhibiting rare fluorite or garnet topologies (see Figure below).[3]In addition, in some cases the incorporation of silicon centers is shown to lead to subtly different chemical and physical properties when compared to their carbon-based analogs leading to novel structural motifs.[4]

Si

NNN

HN

NNN NH

NN N

NH

N NN

HN

M(NO3)

H4ttps

MCl2M=Mn,Cu.CdM=Mn,Cu

flu gar

References1. R.P. Davies, R.J. Less, P.D. Lickiss, K. Robertson, and A.J.P. White, Inorg. Chem. 47, 9958 (2008);

R.P. Davies, R.J. Less, P.D. Lickiss, K. Robertson, and A.J.P. White, Cryst. Growth Des. 10, 4571 (2010).

2. R.P. Davies, P.D. Lickiss, K. Robertson, and A.J.P. White, CrystEngComm 14, 758 (2012)3. I. Timokhin, A.J.P. White, P. D. Lickiss, C. Pettinari, R.P. Davies, CrystEngComm, in press (2014).

DOI: 10.1039/c4ce00486h4. I. Timokhin, J. Baguña Torres, A.J.P. White, P.D. Lickiss, C. Pettinari, R.P. Davies, Dalton Trans. 42,

13806 (2013).

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O-C3-02-06

A versatile approach for the preparation of photoactive hybrid mesoporous titania based materials via sol-gel coordination chemistry

A. Sepulveda1, M. Rico2, C. Ezquerro,1 E. Serrano2, E. Lalinde1, J. Garcia-Martinez1, J.R. Berenguer1

1 Organometallics Molecular Materials, Departamento de Química-Centro de Síntesis Química de La Rioja (CISQ), Universidad de La Rioja, C/ Madre de Dios 51, Logroño, La Rioja, Spain.

2 Molecular Nanotechnology Lab, Inorganic Chemistry Dpt., Universidad de Alicante, Ctra. Alicante-S. Vicente s/n, Alicante, Spain. www.nanomol.es


Titania (TiO2) is one of the most widely used materials in light harvesting systems, despite having a large band-gap (of about 3.0 eV), which only allows it to get about 5% of the solar radiation (U.V.). Usually, visible light-activated titanias are prepared by doping with metal ions or non-metal atoms or by sensitizing with organic dyes or coordination complexes able to absorb in the visible. In this communication we present another unexplored alternative way for the integration of the charge-transfer dyes in the semiconductor titania matrix, allowing also in some cases a considerable reduction in the band gap of the resulting mesoporous hybrid material (anatase structure). This versatile method, based in our “Sol-Gel Coordination Chemistry” approach for the synthesis of hybrid periodic mesoporous Metal Complex-Silica materials,[1] involves the one-pot co-condensation of in situ prepared polymetallic titanium-alkoxide complexes with titanium tetrabutoxide,[2] and has been shown in efficient incorporation not only of organic moieties (Figure 1),[3] but also of neutral or cationic complexes of RuII or IrIII. The photocatalytic activity of the as-synthesized hybrid titanias has been tested in the degradation reaction of Rhodamine 6G under UV and visible irradiation, showing an actually enhanced activity when compared with a similar dye-free titania sample or also with related grafted titanias. Moreover, this hybrid materials show exceptional stability in their use in fluid media, allowing their reusing as catalysts.

Figure 1: Schematic route for the preparation of a hybrid mesoporous organotitania.

References1. E. Serrano, N. Linares, J.R. Berenguer, J. García-Martínez, ChemCatChem 5, 844 (2013) 2. M. Rico-Santacruz, A.E. Sepúlveda, E. Serrano, J.R. Berenguer, E. Lalinde, J. Garcia-Martinez

Spanish Patent 201300536 (2013).3. M. Rico-Santacruz, A.E. Sepúlveda, E. Serrano, E. Lalinde, J.R. Berenguer, J. Garcia-Martinez,

submitted.

A versatile approach for the preparation of photoactive hybrid mesoporous titania based materials via sol-gel coordination chemistry

A. Sepulveda1, M. Rico2, C. Ezquerro,1 E. Serrano2, E. Lalinde1, J. Garcia-Martinez1, J.R.

Berenguer1

1 Organometallics Molecular Materials, Departamento de Química-Centro de Síntesis Química de La Rioja (CISQ), Universidad de La Rioja, C/ Madre de Dios 51, Logroño, La

Rioja, Spain. 2 Molecular Nanotechnology Lab, Inorganic Chemistry Dpt., Universidad de Alicante, Ctra.

Alicante-S. Vicente s/n, Alicante, Spain. www.nanomol.es Presenting author: [email protected]

Titania (TiO2) is one of the most widely used materials in light harvesting systems, despite having a large band-gap (of about 3.0 eV), which only allows it to get about 5% of the solar radiation (U.V.). Usually, visible light-activated titanias are prepared by doping with metal ions or non-metal atoms or by sensitizing with organic dyes or coordination complexes able to absorb in the visible. In this communication we present another unexplored alternative way for the integration of the charge-transfer dyes in the semiconductor titania matrix, allowing also in some cases a considerable reduction in the band gap of the resulting mesoporous hybrid material (anatase structure). This versatile method, based in our “Sol-Gel Coordination Chemistry” approach for the synthesis of hybrid periodic mesoporous Metal Complex-Silica materials,[1] involves the one-pot co-condensation of in situ prepared polymetallic titanium-alkoxide complexes with titanium tetrabutoxide,[2] and has been shown in efficient incorporation not only of organic moieties (Figure 1),[3] but also of neutral or cationic complexes of RuII or IrIII. The photocatalytic activity of the as-synthesized hybrid titanias has been tested in the degradation reaction of Rhodamine 6G under UV and visible irradiation, showing an actually enhanced activity when compared with a similar dye-free titania sample or also with related grafted titanias. Moreover, this hybrid materials show exceptional stability in their use in fluid media, allowing their reusing as catalysts.

Figure 1: Schematic route for the preparation of a hybrid mesoporous organotitania. References 1. E. Serrano, N. Linares, J.R. Berenguer, J. García-Martínez, ChemCatChem 5, 844 (2013) 2. M. Rico-Santacruz, A.E. Sepúlveda, E. Serrano, J.R. Berenguer, E. Lalinde, J. Garcia-

Martinez Spanish Patent 201300536 (2013). 3. M. Rico-Santacruz, A.E. Sepúlveda, E. Serrano, E. Lalinde, J.R. Berenguer, J. Garcia-

Martinez, submitted.

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O-C3-02-07

Mof Crystal Chemistry: The Road To Made-To-Order Materials For Low Concentration Co2 Removal And Air Capture

Osama Shekhah, Youssef Belmabkhout, Zhijie Chen, Vincent Guillerm, Amy Cairns, Karim Adil, and Mohamed Eddaoudi

Functional Materials Design, Discovery & development (FMD3), Advanced Membranes & Porous Materials (AMPM); King Abdullah University of Science and Technology (KAUST), Thuwal 23955-

6900, Kingdom of Saudi Arabia [email protected]

Metal-organic frameworks (MOFs) are regarded nowadays as a promising class of porous materials that are placed to address many enduring societal challenges pertaining to energy and environmental sustainability, due to the prospective ability to mutually control their porous system structure, composition, and functionality. Recently, MOFs were intensively investigated for intermediate and high CO2 concentration removal applications such as post-combustion, pre-combustion capture, natural gas and biogas upgrading.1,2 Nevertheless, the potential of MOFs to remove traces and low CO2 concentration from gas streams was rarely debated.3 The main reason for this lack of studies is that most of MOFs reported so far, with or without unsaturated metal sites (UMC) or/and functionalized ligands, exhibit relatively low CO2 selectivity and uptake particularly at relatively low CO2 partial pressure.

In this presentation, we will show how MOF crystal chemistry enables the elaboration of a series of MOFs, named SIFSIX,4 offering a solution for removal of traces and low concentration of CO2. The results obtained with this family of materials show unprecedented CO2 uptake and selectivity at very low partial pressures relevant to air capture and traces CO2 removal.

References

1 Sumida, K. et al. Chem. Rev. 112, 724-781 (2012).2 Sayari, A. et al. Eng. J. 171, 760-774 (2011).3 24. Xue, D. X. et al. J. Am. Chem. Soc. 135, 7660-7667 (2013)4 Shekhah, O et al. Nat. Commun. (2013) Accepted.

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O-C3-03-02

COLOSSAL MAGNETORESISTANCE AND MAGNETIC ORDERING IN ANTIFERROMAGNETIC MN2+ PNICTIDES

Eve J. Wildman1, Janet M. S. Skakle1, Nicolas Emery2 and Abbie C. Mclaughlin*1

1University of Aberdeen, Meston Walk, AB24 3UE, Aberdeen, UK2Universite Paris Est Creteil, 94320, Thiais, France


We recently reported sizeable negative magnetoresistance (MR) at room temperature in the semi-conducting oxypnictides, LnMnAsO (Ln = Nd, La), which was unprecedented for diavalent Mn materials [1, 2]. High resolution neutron diffraction results showed both compounds to be antiferromagnetic (TN (Mn) ~370K), revealing a spin reorientation of Mn2+ spins below TN (Nd) = 23K for NdMnOAs. Electron doping was performed by substitution of F- for O2- in the series NdMnAsO1-xFx (x = 0 – 0.08). Surprisingly colossal magnetoresistance (CMR) is observed at low temperatures (Figure 1) [3].

We offer a novel mechanism for CMR, as variable field measurements indicate a transition from an antiferromagnetic state in zero field, to a paramagnetic state in high fields. The MR is related to the magnitude of the antiferromagnetically ordered Mn2+ moment so

that -

2/1

∆=

CMMR

; DM = M(0) – M(H), where M(H) is the Mn2+ moment in field, M(0) is the Mn2+ moment when m0H = 0 T and C is a constant (0.4 mB at 4 K).

Hole-doped arsenides Nd1-xSrxMnOAs (x ≤ 1.0) have also been investigated, which in contrast show positive MR and are driven from semi-conducting to metallic behaviour at doping levels x ≥ 0.05. The structure and properties of these compounds are explored in order to demonstrate that various MR mechanisms are apparent in novel Mn oxyarsenides.

References1. N. Emery, E. J. Wildman, J. M. S. Skakle, G. Giriat, R. I. Smith and A. C. Mclaughlin, Chem. Comm. 46, 6777 (2010).2. N. Emery, E. J. Wildman, J. M. S. Skakle, R. I. Smith, A. N. Fitch and A. C. Mclaughlin, Phys. Rev. B 83, 14429 (2011).3. E. J. Wildman, J. M. S. Skakle, N. Emery and A. C. Mclaughlin, J. Amer. Chem. Soc. 134, 8766 (2012).

Figure 1 : Magnetotransport data for NdMnAsO1-xFx - The variation of MR with temperature for x = 0.050, 0.065 and 0.080 evidencing CMR at low temperature in a 7T field.

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O-C3-03-03

PROTONATION-DEPENDENT LUMINESCENCE OF A PLATINUM DITHIOLENE SALT SHOWING STRONG EMISSION IN SOLUTION

S. Attar,1 D. Espa,1 F. Artizzu,1 E. Sessini,1 M. L. Mercuri, 1 A. Serpe, 1 L. Marchiò, 2 P. Deplano1

1Dipartimento di Scienze Chimiche e Geologiche, Università di Cagliari, Monserrato, I-09042 Cagliari, Italy

2Dipartimento di Chimica, Parco Area delle Scienze, 17/A, I-43100, Parma, ItalyPresenting author: [email protected]

Metal dithiolene complexes form a well know class of complexes exhibiting a wide range of properties of interest in materials and in bioinorganic fields [1]. The red-ox active 1,2-enedithiolate anions are capable to coordinate a variety of metals as neutral dithioketones, as ene-1,2-dithiolate dianions, as mixed-valence thioketone-radical thiolate monoanions. Non-classical Lewis descriptions are required to describe the mono-anionic complexes of d8metals of the nickel triad, where the MII is coordinated formally to one dithiolato ligand (L2-) and one ligand in radical form (L-•). Recent results show that a monoanionic nickel dithiolene [2], similarily to what happens with cobalt ones [3], can work as electro-catalysts for proton reduction. Suitable ligands (L) such as [4’, 5’: 5, 6][1,4]dithiino[2,3-b]quinoxaline-1’,3’dithiolate can allow to prepare sufficiently stable monoanionic species and nickel complexes with this ligand have been previously investigated for their properties as NIR-dyes [4]. We report here additional remarkable properties in the solid state and in solution of the platinum salt C[PtL2] (1) where C is [(R)-Ph(Me)HC*-NMe3]

+ and L the above cited ligand. 1 crystallizes in the chiral space group P1 due to the presence of the enantiopure cation (R)-Ph(Me)HC*-NMe3

+ (Fig. 1). Moreover this salt exhibits a solution room temperature emission at 567 nm. This emission nm is proton dependent, (Fig. 2), and this makes this complex a potential proton sensor. Remarkably this salt does not emit in the solid state. Experimental and theoretical studies are in course to deep the knowledge of these systems.

Figure 1: Molecular structure of (R)-Ph(Me)HC*-NMe3[Pt(L)2]·DMF

Figure 2: Emission spectra of 1 at 298 K in acetone showing lem 568 nm decrease for HCl addition

References1. Dithiolene Chemistry: Progress in Inorganic Chemistry, Vol. 52, E. I. Stiefel (Ed.), John Wiley & Sons,

Chichester, 2004; P. Deplano et al. Coord. Chem. Rev., 254, 1434 (2010).2. S. Sarkar et al., Chem. Eur. J., 16, 12324 (2010).3. R. Eisenberg et al., J. Am. Chem.. Soc., 133, 15368 (2011).4. J-L. Zuo et al., Dyes and Pigments, 92, 1223 (2012).

Aknowledgements: This work is performed inside COST action CM1202 Perspect-H2O and is supported by Università di Cagliari and Fondazione Banco di Sardegna

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O-C3-03-04

A CUSTOM CELL FOR IN-SITU STUDIES OF MATERIALS FORMATION

Y. Wu,1 D. O’Hare.1

1Department of Chemistry, University of Oxford, Oxford OX1 3TA, UKPresenting author: [email protected]

We present work on the development and usage of an IR furnace cell (‘ODISC’, the Oxford-Diamond In-Situ Cell – fig. 1), an instrument that makes possible in-situ characterisation of the formation of nanoporous framework materials under a wide range of conditions. We have been able to obtain good quality in-situ data that is both temperature and time resolved, using angular-dispersive diffraction. This enables us to obtain structural data on intermediates and products, using Rietveld refinement, as well as information on kinetics and particle sizes.

Figure 1: Schematic and photo of the ODISC furnace set-up from Moorhouse et al. [1]

Some results obtained using the ODISC cell are presented. We demonstrate that several common families of coordination framework materials (or ‘MOFs’) such as the pillared-paddlewheel and MOF-5 frameworks form through metastable intermediate phases, which we have been able to characterise structurally and kinetically from in-situ data. These experiments provide an insight into the pathways by which the archetypical MOF materials are formed, allowing further refinement of synthetic techniques.

We welcome expressions of interest for collaborative experiments using this system. We are currently developing ODISC so that it can be used as a user facility on beamline I12 at the Diamond synchrotron. The heating capability is both precise and rapid, reaching 1200-1300 °C in less than ten seconds. The wide-bore design and interchangeable reaction vessels allow a wide range of different reactions to be studied from moderate to extremely high temperatures. Previous examples include solvothermal synthesis using a full autoclave setup with stirring, and high-temperature molten salt reactions.

References1. S. J. Moorhouse, N. Vranješ, A. Jupe, M. Drakopoulos, D. O’Hare, Review of Scientific Instruments

v.83, 084101 (2012)

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O-C3-03-05

Multimetallic compounds and functionalised nanoparticles for catalysis, imaging and sensing

Dr James Wilton-ElyDepartment of Chemistry, Imperial College, London

The careful design of bifunctional linkers can be used to transform monometallic systems into multi-metallic compounds or functionalised nanomaterials [1-6]. The potential offered by the complemen-tary action of different metals tailored for specific applications within the same assembly is vast. This presentation will describe how simple precursors can be used as the basis for heteropolymetallic com-pounds and functional nanoparticles, applied to catalysis of cycloaddition reactions [7], magnetic reso-nance imaging [8] and carbon monoxide sensing [9]. Underpinning this approach is the careful choice of sulfur, nitrogen and oxygen donor combinations, which determine the coordination chemistry ob-served. The methodology developed also allows the construction of nanoparticles with mixed surface functionality, which adds a further element of control to the reactions taking place at the surface. Using nanoparticles with a magnetic core, separation and reuse becomes far simpler, minimising work up procedures and the amount of waste produced [7].

[1] Wilton-Ely et al, Inorg. Chem., 2008, 47, 9642; [2] Wilton-Ely et al, Organometallics, 2009, 28, 197; [3] Wilton-Ely et al, Organometallics, 2010, 29, 2547; [4] Wilton-Ely et al, Inorg. Chem. 2009, 48, 3866; [5] Wilton-Ely et al, Inorg. Chem. 2013, 52, 4700; [6] Wilton-Ely et al, Inorg. Chem. 2014, 53, 2404; [7] Wilton-Ely and Díez-González, Chem. Commun. 2013, 49, 11358; [8] Wilton-Ely et al, Inorg. Chem. 2014, 53, 1989; [9] Wilton-Ely, Martínez-Máñez et al, Angew. Chem. Int. Ed., 2014, in press.

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O-C3-04-02

NON-BIOACCUMULABLE LOW SURFACE ENERGY MATERIALS

J. El Maissa, T. Darmanina, E. Taffin De Givenchya, J. Eastoeb, M. Sagisakac,

F. Guittarda

a Univ. Nice Sophia-Antipolis, CNRS, Equipe Surfaces et Interfaces, Parc Valrose, 06100 Nice- France

b School of Chemistry, University of Bristol, Cantock’s Close, Bristol BS8 1TS, U.Kc Department of Frontier Materials Chemistry, Graduate School of Science and Technology, Hirosaki

University, 3 Bunkyo-cho, Hirosaki, Aomori 036-8561, JAPAN *E-mail: [email protected]

Due to the unique properties of the fluorine atom, “Low Surface Energy Materials” made from fluor-inated compounds, combined to surface structures at micro/nano scale can generate superhydropho-bocity, an indispensable property for practical applications such as self-cleaning windows, antibac-terial surfaces, and anticorrosion. Superhydrophobic surfaces can be elaborated by electrodeposition of conducting polymers. Modifying the chemical structure (intrinsic hydrophobicity) of the monomer can induce changes in surface morphology. Usually, the fluorinated chains are used because they are intrinsically both hydrophobic and oleophobic [1, 2].

However compounds with long fluorinated chains (more than seven methylene units) are known to be bio-persistent [3] in organisms. Perfluorinated compounds were detected in the tissues of humans and wild. Life, including, fish, birds, and marine mammals [4]… To overcome this problem, the utilization of short fluorinated chains is recommended conserving both characteristics (hydrophobicity and oleophobicity), and will allow the development of a new generation of environmentally responsible materials.

This project is centered on intelligently programmed molecular design of monomers with low fluo-rine contents. It involves the design and synthesis of new monomers replacing long fluorocarbon chain while conserving their particular properties. We will report the synthesis, surface morphology and the wettability of these environmental responsible materials.References1- T. Darmanin, F. Guittard, Prog. Polym. Sci, DOI: http://dx.doi.org/10.1016/j.progpolymsci.2013.10.003.2- H. Bellanger, T. Darmanin, F. Guittard, Chem. Rev, vol. 114, no. 5, pp. 2694-2716, (2014).3- K. Kannan, S. Corsolini, J. Falandysz, G. Fillmann, K. S. Kumar, B. G. Loganathan, M. A. Mohd, J. Olivero, N. Van Wouwe, J. H. Yang, K. M. Aldoust. Environ. ScI. Technol., vol. 38, no. 17, pp. 4489–4495, (2004).4- E. I. H. Loi, L. W. Y. Yeung, S. Taniyasu, P. K. S. Lam, K. Kannan, and N. Yamashita, Environ. Sci. Technol., vol. 45, no. 13, pp. 5506–13, (2011).

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O-C3-04-03

THEORETICAL STUDY ON THE OPTICAL ACTIVITY OF METAL-HELICENE SYSTEMS: TOWARDS A RATIONAL DESIGN OF REDOX-TRIGGERED CHIROPTICAL

SWITCHES

M. Srebro1, J. Autschbach2, J. Crassous3

1Department of Theoretical Chemistry, Faculty of Chemistry, Jagiellonian University, R. Ingardena 3, 30-060 Krakow, Poland

2Department of Chemistry, University at Buffalo, State University of New York, Buffalo, NY 14260-3000, USA

3Institut des Sciences Chimiques de Rennes, UMR 6226, Institut de Physique de Rennes, UMR 6251, Campus de Beaulieu, CNRS-Universite de Rennes 1, 35042 Rennes Cedex, France


Due to their large-magnitude chiroptical properties, helical derivatives have been attracting a great deal of attention as potential materials for non-linear optics, wave guides, switches, luminescent materials, and sensors. The main challenge for the molecular engineering of helical systems toward functional materials is the discovery and development of efficient synthetic routes and simple strategies to improve and tune their chiroptical properties. In this research the importance of first-principles calculations cannot be understated, since they can provide direct information on how experimentally measured properties depend on atomic-scale structure and bonding. Accordingly, they do not only enable a meaningful interpretation of experimental data, but may also lead to a deeper understanding of the factors responsible for the observed experimental trends. This is the first step in enabling the possibility of designing and proposing new systems with the desired properties.

The main goal of this study was to explore factors determining chiroptical switching in metal-helicene systems. Recently, the first electrochemical chiral switch based on a pure helicene moiety bound to

a 5-coordinate Ru center via a vinyl bridge has been proposed [1]. The CD spectrum of this system undergoes significant and reversible changes as the metal oxidation state switches between RuII and RuIII, and as the quantum-chemical analysis has shown, this is due to the vinyl bridge because it allows the metal oxidation to affect the helicene chromophore (Figure 1). The calculated spin density of the Ru(III) species demonstrates a high degree of delocalization – the unpaired charge density is not only localized on the metal atom but also spread out over the helicene p-ligand. Variations of (i) a metal center (Fe, Ru, Os), (ii) its coordination sphere (5 vs. 6-coordinated), and (iii) an electron withdrawing and donating substituent (CN, NH2, NO2, OCH3) at the helicene are examined here and analyzed in terms of their influence on OR and CD as possible factors which may determine the effectiveness of chiroptical switching.

References1. E. Anger, M. Srebro, N. Vanthuyne, L. Toupet, S. Rigaut, C. Roussel, J. Autschbach, J. Crassous, R.

Réau, J. Am. Chem. Soc. 134, 15628 (2012).

Figure 1: Ru-vinylhelicene redox switch. [1]

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O-C4-01-03

Reduction of Carbon Dioxide to Multicarbon Covalent Chemical Bonds by Bio-electrochemical Process

1 Farooq R*, 2Sloan T William1Department of Chemical Engineering, COMSATS Institute of Information Technology, Lahore, Paki-

stan; *[email protected] 2Department of Infrastructure and Environment, University of Glasgow, Glasgow, G12 8QQ, Scot-

land, UK

Abstract

The present study demonstrates the potential of renewable biochemical synthesis from atmospheric CO2. The acetogenic anaerobic bacteria Sporomusa Ovata was used for fixing carbon dioxide into covalent chemical bonds. The bioelectrochemical cell (BEC) developed in this study is not previous-ly used in bio-electrochemical synthesis. The characterization of biosynthesized products shows the presence of acetate and small amount of ethanol, n-butyric acid and iso-pentanoic acid. The amount of acetate produced is 142.9 mg/L in 72 hours which is four times higher than previously reported and is attributed to improved reactor design. The second major product is ethanol which is formed due the conversion of acetaldehyde into ethanol in solventogenesis process. The bioelectrosynthesis of etha-noic acid, ethanol, n-butanoic acid and iso-pantanoic acid showed that S.Ovata has consumed electric current and reduced inorganic carbon dioxide to organic acids. The acetate synthesis by bioelectro-chemical process is 128% improved as compared to biochemical process. The average rate of acetate synthesis in bioelectrochemical process is observed to be 1.3±0.67mgL-1h-1. The columbic acetate re-covery in bioelectrochemical process was found to be 24.6%. The results show that the percentage appearance of electrons in acetate by S.Ovata is 45±7% which is a function of electrodes surface area (1257mm2). The electron recovery in current study is approximately four times higher if it is compared with the area of electrode of previous research. In current study, increased amount of bioacetate pro-duced and increased recovery of electrons as organic compounds are important finding. It opens up the prospects of developing processes for the biosynthesis of organic chemicals from electrons derived from renewable energies and harvesting waste greenhouse gases without exerting pressure on the use of agricultural land or fossil fuels.

Keywords: Anaerobic fixing of CO2, bioelectrochemical synthesis, living biocatalyst, columbic acetate recovery, fixing greenhouse gas in organic acids, recovery of electrons

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O-C4-01-05

NEW INSIGHTS ON DYE-ELECTRODE INTERFACE IN P-TYPE DYE-SENSITIZED SOLAR CELLS: A FIRST-PRINCIPLES

STUDY

Ana B. Muñoz-García,1 Michele Pavone.1

1Department of Chemical Sciences, University of Naples Federico II, Comp. Univ. Monte Sant’Angelo – Via Cintia 21, 80126, Naples, Italy.


Solar energy represents a clean option to deplete the use of fossil fuels as energy source. Thanks to the low manufacturing costs, dye-sensitizer solar cells (DSSCs) are attractive alternatives to the expensive solid-state photovoltaic technologies. Original DSSC-based photoanodes (n-DSSCs), as pioneered by Grätzel [1], have great potential for achieving high efficiencies when combined with photo-active counter electrodes or photocathodes that are DSSC themselves (p-DSSC) in so-called tandem cells [2]. Two decades of intensive research have brought n-DSSCs close to commercial applications [3], with efficiencies near ~13% [4]. However, the poor efficiency of the much less studied p-DSSCs (tipically ~0.5% [5]) wrecks the foreseen development of tandem devices. Thus, a deeper understanding of structure-function relationships in current p-DSSC materials and devices is crucial to enable further advancements in this field. In this context, first-principles computational tools can paly a crucial role to dissect the observed opto-electronic properties in terms of electronic and structural features at the nano-scale.Here, we present a first-principles study, based on Density Functional Theory, on a prototypical p-DSSC photocathode made of nickel oxide (NiO) and coumarin-based dyes [6]. We address the structural and energetic differences of several anchoring groups on the NiO surface. Then, we discuss how the dye-NiO mutual interactions affect the electronic structure of the interface, highlighting the effects on the corresponding charge transfer processes.

Figure 1: NiO(001)/C343 model systemOur quantum-mechanical analyses of dye-electrode interfacial features provide new insights on p-type DSSCs and pave the route to the rational design of improved photocathodes for p-type and DSSC based tandem solar cells.

References1. B. O’Regan, M. Grätzel, Nature 353, 737 (1991)2. A. Hagfeldt et al. Chem. Rev. 110, 6595 (2010)3. L. Moreira Gonçalves et al. Energy Environ. Sci. 1, 655 (2008)4. A. Yella et al. Science 334, 629 (2011)5. F. Odobel,Y. Pellegrin J. Phys. Chem. Lett. 4, 2551 (2013)6. A. Morandeira et al. J. Phys. Chem. C 112, 9530 (2008)

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O-C4-02-02

Nanocomposites for energy applications

Noelia M. Sanchez-Ballester1, H. Abe2, G. Rydzek,1 D. Walsh,3 K. Ariga.1

1Supermolecules Group, National Institute for Materials Science, 1-1 Namiki, Tsukuba, Ibaraki, 305 0044, Japan.

2 National Institute for Materials Science, 1-2-1 Sengen, Tsukuba, Ibaraki, 305-0047, Japan.3Department of Chemistry, University of Bath, Claverton Down, Bath, BA2 7AY, UK.

Our research interests include the development of controlled polymer architectures, alloys, coordination complexes and nanocomposites for energy related applications such as remediation reactions, water splitting and supercapacitors. [1-3] This presentation will provide an overview of recent progress in the development of new chelate stabilized oxides catalysts for water oxidation under visible light producing a superior O2 output of 85% maximum theoretical yield. [4] Also the use of novel inorganic-polymer and inorganic nanocomposites composites for low temperature NO remediation reactions will be presented (Figure 1). [5] In general, this work address cost (by using high natural abundance elements), the toxicity of the catalysts is minimized and longevity of the reactions is also targeted.

Fgure 1: Examples of the nanostructured catalysts included in this work.

References1. H. Palza, A. Maturana, F. Gracia, A. Neira, V.M. Fuenzalida, J. Avila, N.M. Sanchez-Ballester, M.R.J.

Elsegood, S.J. Teat, K. Ariga and J.P. Hill, JNN, 12, 1 (2012). 2. L.K. Shrestha, M. Sathish, J. P. Hill, K. Miyazawa, T. Tsuruoka, N.M. Sanchez-Ballester, I. Honma, Q. Ji and

K. Ariga, J. Mater. Chem. C, 1, 1174 (2013).3. S. Mandal, L. Michael, J. Hill, A. Vinu and K. Ariga, JNN, 10,(2010).4. D. Walsh, N.M. Sanchez-Ballester, K. Ariga, A. Tanaka and M. Weller, Manuscript Submitted, (2014). 5. N.M. Sanchez-Ballester, T. Tanabe, G.V. Ramesh, J.P. Hill, L. Kumar, K. Ariga, Y. Lvov and H. Abe, Manuscript

Submitted, (2014).

Nanocomposites for energy applications

Noelia M. Sanchez-Ballester1, H. Abe2, G. Rydzek,1 D. Walsh,3 K. Ariga.1 1Supermolecules Group, National Institute for Materials Science, 1-1 Namiki, Tsukuba,

Ibaraki, 305 0044, Japan. 2 National Institute for Materials Science, 1-2-1 Sengen, Tsukuba, Ibaraki, 305-0047, Japan.

3Department of Chemistry, University of Bath, Claverton Down, Bath, BA2 7AY, UK.

Our research interests include the development of controlled polymer architectures, alloys, coordination complexes and nanocomposites for energy related applications such as remediation reactions, water splitting and supercapacitors. [1-3] This presentation will provide an overview of recent progress in the development of new chelate stabilized oxides catalysts for water oxidation under visible light producing a superior O2 output of 85% maximum theoretical yield. [4] Also the use of novel inorganic-polymer and inorganic nanocomposites composites for low temperature NO remediation reactions will be presented (Figure 1). [5] In general, this work address cost (by using high natural abundance elements), the toxicity of the catalysts is minimized and longevity of the reactions is also targeted.

Fgure 1: Examples of the nanostructured catalysts included in this work.

References 1. H. Palza, A. Maturana, F. Gracia, A. Neira, V.M. Fuenzalida, J. Avila, N.M. Sanchez-Ballester,

M.R.J. Elsegood, S.J. Teat, K. Ariga and J.P. Hill, JNN, 12, 1 (2012). 2. L.K. Shrestha, M. Sathish, J. P. Hill, K. Miyazawa, T. Tsuruoka, N.M. Sanchez-Ballester, I.

Honma, Q. Ji and K. Ariga, J. Mater. Chem. C, 1, 1174 (2013). 3. S. Mandal, L. Michael, J. Hill, A. Vinu and K. Ariga, JNN, 10,(2010). 4. D. Walsh, N.M. Sanchez-Ballester, K. Ariga, A. Tanaka and M. Weller, Manuscript Submitted,

(2014). 5. N.M. Sanchez-Ballester, T. Tanabe, G.V. Ramesh, J.P. Hill, L. Kumar, K. Ariga, Y. Lvov and H.

Abe, Manuscript Submitted, (2014).

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O-C4-02-03

Cobalt(III) Complexes as p-Type Dopants in Solid-State Dye-sensitized Solar Cells

F. Kessler1,2, J. Burschka1, Md. K. Nazeeruddin1, M. Grätzel1

1Laboratory of Photonics and Interfaces, Institute of Chemical Sciences and Engineering, School of Basic Sciences, Swiss Federal Institute of Technology (EPFL), CH-1015 Lausanne, Switzerland

2Present Address: Siemens AG, Corporate Technology, CT RTC MAT IEC-DE, Günther-Scharowsky Strasse 1, 91058 Erlangen, Germany


Dye-sensitized solar cells (DSC) are a promising alternative to its cost intensive silicon-based counterparts. A solid-state DSC is composed of two conductive substrates, a sensitized, porous structured metal oxide semiconductor and a hole transporting layer. To achieve sufficient conductivity p-type doping of the hole transport material is necessary. However, no detailed study on p-type doping in solid-state DSC has been reported. Herein we report the use of novel cobalt(III) complexes as p-type dopants for spiro-MeOTAD, the most common hole transporting material in ssDSC. The synthesis of the materials as well as the doping mechanism and influence of doping concentration are discussed. Using a recently reported D-p-A sensitizer, we finally reached a record photon-to-current efficiency of 7.2% under standard test conditions.[1-4] The most solvable dopant FK209 was commercialized just recently by Luminescence Technology Corp. (Lumtec).

Figure 1: Structures of cobalt-based conductivity dopants FK102, FK209 and FK269 and influence of doping concentration on absorption and dye-sensitized solar-cell performance.

References1. J. Burschka, A. Dualeh, F. Kessler, E. Baranoff, N.-L. Cevey-Ha, C. Yi, Md. K. Nazeeruddin, M.

Grätzel, J. Am. Chem. Soc., 2011, 133, 18042.2. J. Burschka, F. Kessler, Md. K. Nazeeruddin, M. Grätzel, Chem. Mater., 2013, 25, 2986.3. N. M. Shavaleev, F. Kessler, M. Grätzel, Md. K. Nazeeruddin, Inorg. Chim. Acta, 2013, 407, 261.4. J. Burschka, F. Kessler. E. Baranoff, Md. K. Nazeeruddin, M. Grätzel, WO2012/114316A1.

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O-C4-02-04

DIBENZOFULVENE-BASED DYES FOR EFFICIENT DSSCs.

A.-L. Capodilupo1, L. De Marco2, E. Fabiano1, R. Giannuzzi2, G. Gigli1,2,3 and G. Ciccarella.* 1,4

1Istituto Nanoscienze – CNR, National Nanotechnology Laboratory (NNL), Via Arnesano, 73100 Lecce, Italy

2Center for Biomolecular Nanotechnologies (CBN) Fondazione Istituto Italiano di Tecnologia (IIT), Via Barsanti 1, Arnesano, 73010, Italy

3Dipartimento di Matematica e Fisica “Ennio De Giorgi”, Università del Salento, Via Monteroni, 73100, Lecce, Italy.

4Dipartimento di Ingegneria dell’Innovazione, Università del Salento, Via Monteroni, 73100, Lecce, Italy.


Dye sensitized solar cells (DSSCs) represent one of the most promising next-generation photovoltaic devices. These devices have been attracting considerable attention due to high performance and low-cost production. Dyes as photosensitizers are one of the most important components influencing the photovoltaic performances of DSSCs, because they determine the photoresponse range of the device and initiate the primary steps of the photon absorption and the subsequent electron transfer process. In addition to conventional Ru-complex sensitizers, metal-free organic dyes have also been utilized as sensitizers in DSSCs, and the photovoltaic performance of DSSCs based on organic-dye sensitizers has been improved by careful molecular design. [1,2]We have designed and synthesized three novel organic dyes containing two donor moieties bonded to the dibenzofulvene core Fig.1, with several thiophene spacer-linker forming a 2D-π-A push-pull system, to improve solar-cell performance of the solar cells. The DSSCs based on the TK3 dye showed high power conversion efficiency of 7.45%.

DIBENZOFULVENE-BASED DYES FOR EFFICIENT DSSCs.

A.-L. Capodilupo1, L. De Marco2, E. Fabiano1, R. Giannuzzi2, G. Gigli1,2,3 and G.

Ciccarella.* 1,4

1Istituto Nanoscienze – CNR, National Nanotechnology Laboratory (NNL), Via Arnesano, 73100 Lecce, Italy

2Center for Biomolecular Nanotechnologies (CBN) Fondazione Istituto Italiano di Tecnologia (IIT), Via Barsanti 1, Arnesano, 73010, Italy

3Dipartimento di Matematica e Fisica “Ennio De Giorgi”, Università del Salento, Via Monteroni, 73100, Lecce, Italy.

4Dipartimento di Ingegneria dell'Innovazione, Università del Salento, Via Monteroni, 73100, Lecce, Italy.


Dye sensitized solar cells (DSSCs) represent one of the most promising next-generation photovoltaic devices. These devices have been attracting considerable attention due to high performance and low-cost production. Dyes as photosensitizers are one of the most important components influencing the photovoltaic performances of DSSCs, because they determine the photoresponse range of the device and initiate the primary steps of the photon absorption and the subsequent electron transfer process. In addition to conventional Ru-complex sensitizers, metal-free organic dyes have also been utilized as sensitizers in DSSCs, and the photovoltaic performance of DSSCs based on organic-dye sensitizers has been improved by careful molecular design. [1,2] We have designed and synthesized three novel organic dyes containing two donor moieties bonded to the dibenzofulvene core Fig.1, with several thiophene spacer-linker forming a 2D-π-A push-pull system, to improve solar-cell performance of the solar cells. The DSSCs based on the TK3 dye showed high power conversion efficiency of 7.45%.

Figure 1: .TK3 structure and Photovoltaic parameters for DSSC.

References 1. A. Scrascia, L. De Marco, S. Laricchia, R. A. Picca, C. Carlucci, E. Fabiano, A. L.

Capodilupo, F. Della Sala, G. Gigli and G. Ciccarella, J. Mater. Chem. A 1, 11909 (2013). 2. A. Scrascia, M. Pastore, L. Yin, R. A. Picca, M. Manca, Y.-C. Guo, F. De Angelis, F. Della

Sala, R. Cingolani, G. Gigli and G. Ciccarella, Current Organic Chemistry, 19, (2011), 3535.

Figure 1: .TK3 structure and Photovoltaic parameters for DSSC.

References1. A. Scrascia, L. De Marco, S. Laricchia, R. A. Picca, C. Carlucci, E. Fabiano, A. L. Capodilupo, F.

Della Sala, G. Gigli and G. Ciccarella, J. Mater. Chem. A 1, 11909 (2013).2. A. Scrascia, M. Pastore, L. Yin, R. A. Picca, M. Manca, Y.-C. Guo, F. De Angelis, F. Della Sala, R.

Cingolani, G. Gigli and G. Ciccarella, Current Organic Chemistry, 19, (2011), 3535.

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O-C4-02-05

RIGID BIIMIDAZOLE ANCILLARY LIGANDS AS AN AVENUE TO BRIGHT DEEP BLUE CATIONIC IRIDIUM (III) COMPLEXES

A. F. Henwood,1 S. Evariste,2,3 A. M. Z. Slawin,1 E. Zysman-Colman.1

1EaStCHEM School of Chemistry, University of St Andrews, St Andrews, Fife, UK, KY16 9ST, Fax: +44-1334 463808; Tel: +44-1334 463826; E-mail: [email protected]

2Département de Chimie, Université de Sherbrooke, 2500 Boul. de l’Université, Sherbrooke, QC, Canada, J1K 2R1

3Sciences Chimiques, UMR 6226 CNRS - Université de Rennes 1, Campus de Beaulieu, Rennes Cedex, France 35042

URL: http://www.zysman-colman.comPresenting author: [email protected]

Light Emitting Electrochemical Cells (LEECs) offer an exciting alternative to OLEDs as a next generation solid state lighting (SSL) technology: their simplified device architecture facilitates straightforward device fabrication processes, drastically reducing costs. However, a dearth of bright blue emitting materials for these devices has so far retarded the achievement of bright true white light emission. We have undertaken to rectify this by employing a combination of computational modelling and rational ligand design to hypothesise new strategies and identify suitable candidates for achieving bright, deep blue emitting cationic iridium complexes. In this talk, we demonstrate a successful example of this process with the synthesis and photophysical characterization of a series of three analogous complexes with photoluminescent quantum yields (PLQYs) ranging from 2 to 68% in the deep blue region of the spectrum, and elucidate the origin of this behaviour through computation and experiment.

Figure 1: Quantum yield disparity across our complex series.

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O-C4-02-06

Molecular Highways in Zeolites: from the Lab to the Refinery

Grau-Atienza1, E. Li2, J. Valla2,3, J. Garcia-Martinez1,2

1Molecular Nanotechnology Lab, Inorganic Chemistry Dpt., Universidad de Alicante, Ctra. Alicante-S. Vicente s/n, Alicante, Spain. www.nanomol.es

2 Rive Technology, Inc., 1 Deer Park Drive, Suite A, Monmouth Junction, NJ 08852, USA 3 Department of Chemical and Biomolecular Engineering University of Connecticut Storrs, CT 06269

(USA)Presenting author: [email protected]

The small size of the micropores in zeolites causes slow diffusion of reactant and product molecules in and out of the pores, and negatively impacts the product selectivity of zeolite based catalysts, e.g. fluid catalytic cracking (FCC) catalysts. We introduced size-tailored mesoporosity into commercial zeolite Y crystals by a simple surfactant-templating post-synthetic modification process that can be tuned by the size of the surfactant micelles [1]. Herein, we present unambiguous evidence of the presence of surfactant-templated intracrystalline mesoporosity in zeolites and the first example of commercial application of hierarchical zeolites on an industrial scale. Zeolite Y is the most widely used zeolite in catalysis and the developments in mesoporous Y reflect the general “landscape” of mesoporous zeolites. The preparation of mesoporous Y, the materials’ properties, and their catalytic application in fluid catalytic cracking (FCC) and hydrocracking will be critically reviewed. Finally, the scale-up and use of mesostrutured zeolite Y on an industrial scale will be presented, which demonstrate, for the first time, the promising future of hierarchical zeolites in large scale industrial applications [2].

Figure 1: Observed trends during a trial at Alon’s Big Spring, Texas refinery of our catalyst (blue) in comparison with a conventional one (green): (left) increased feed rate by 700 BPSD (barrel per stream day) and (right) an incremental value uplift owing to the change-out of the incumbent catalyst for Rive’s MH-1 catalyst that contained mesostructured Y zeolite.

References1. J. Y. Ying, J. Garcia-Martinez, US20050239634 (2005); b) J. Garcia-Martinez, M. Johnson, J. Valla,

K. Li, J. Y. Ying, Catal. Sci. Technol. 2, 987 (2012); 2 J. Garcia-Martinez, K. Li, G. Krishnaiah, Chem. Commun. 48, 11841 (2012); b) K. Li, J. Valla, J.

Garcia-Martinez, ChemCatChem 6, 46 (2014).

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O-C4-03-02

High-throughput computational discovery of small molecules for flow batteries

Süleyman Er1,2, Changwon Suh1, and Alán Aspuru-Guzik1

1Department of Chemistry and Chemical Biology, Harvard University, Cambridge, MA, USA2Molecular Materials and Nanosystems, Eindhoven University of Technology, Eindhoven, The Neth-

erlands

Quinones are small, cyclic, organic molecules that are abundant in nature, found commonly in plants and petroleum [1]. Together with our collaborators from Harvard, we recently showed that the attrac-tive electrochemical properties of quinones are useful for grid-scale electrical energy storage [2, 3]. Tuning the key properties of quinones, such as the redox potential and the solubility, is possible via addition of functional chemical groups to quinones.

It has become increasingly important to rapidly and accurately predict the properties of molecular materials. Traditional development of new molecular materials is largely based on empirical intuition or experience with a certain family of chemical compounds. However, this approach is limited to the characterization of only a handful of compounds per year, and the size of the molecular search space of the functionalized quinone molecules is beyond the reach. Thus, current challenges in the discovery of new quinone-based compounds primarily arise from the difficulty of exploring an unlimited number of possible molecular structures. High-throughput methods utilizing first-principles calculations provide a fast and robust way to access the materials properties.

To identify new electrode materials for flow batteries from a pool of candidate molecules, we first de-veloped a virtual library of small organic molecules. This molecular library is being actively populated in cooperation with our collaborators at Harvard. Using state-of-the-art computing resources we are able to screen a large number of candidate molecules at the level of density functional theory. To date, we successfully predicted the redox properties of more than 10,000 molecules. In this presentation, we will introduce our computational approach for finding new organic molecules for flow batteries. We will detail some of the important structure-property relationships of the studied molecules, and show the importance of theoretically predicted key materials properties for the design and engineering of new molecules.References:

[1] http://en.wikipedia.org/wiki/Quinone

[2] B. Huskinson, M. P. Marshak, C. Suh, S. Er, M. R. Gerhardt, C. J. Galvin, X. Chen, A. Aspuru-Guz-ik, R. G. Gordon, and M. J. Aziz. A metal-free organic–inorganic aqueous flow battery. Nature, 505, 195–198 (2014).

[3] R. F. Service. Tanks for the Batteries. Science 344, 352-354 (2014).

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O-C4-03-03

RED-ABSORBING CATIONIC ACCEPTOR DYES FOR PHOTOCATH-ODES IN TANDEM SOLAR CELLS

Christopher J Wooda, Ming Chengb, Licheng Sunb, Xichuan Yangb, Elizabeth A Gibsona

aSchool of Chemistry, University of Nottingham, University Park, Nottingham, NG7 2RD, UK.bDUT-KTH Joint Research Centre on Molecular Devices, State Key Laboratory of Fine Chemicals,

Dalian University of Technology (DUT), Dalian, China.

Tandem Dye sensitised solar cells (DSSCs) are a promising modification to existing n-type DSSCs. Wherein a dye sensitised photocathode is used in place of the passive counter electrode, enabling the absorption of a broader range of photons. However the majority of high performance dyes for photo-cathodes absorb higher energy photons causing spectral overlap with the n-type photoanode. A series of new donor-π-acceptor dyes which absorb towards the red region of the visible spectrum (CAD 1-3) were synthesised incorporating indolium cationic acceptor units. Their optical and electrochemical properties show the energy levels are better matched for use with the I3

-/I- redox couple in NiO-based p-type DSSCs. NiO-based p-type DSSCs with CAD 1, CAD 2 and CAD 3 gave photocurrents of 3.6, 3.3 and 6.2 mA cm–2 respectively. The photocurrent given by CAD 3 is to our knowledge the highest for a p-type DSSC. This can be attributed to a very broad absorption across the visible-NIR spectrum making it ideal for use in tandem DSSCs. In addition the effect of dye structure on detrimental charge recombi-nation processes was investigated by transient absorption, time resolved IR and SSWM photovoltage measurements.

ECB, TiO2

VOC

TiO2 Photoanode

E

Evb, NiO

EF, NiO

NiO Photocathode

D/ D-

D*/ D-

D*/ D+

D/ D+

I3-

I-

e-

e-

e-

e-

EF, TiO2

N

COOH

R

S

NC6H13

R=

S

N

C6H13

OC6H13

C6H13O

H

CAD 1

CAD 2

CAD 3

1. C. J. Wood, M. Cheng, C. Clark, R. Horvath, I. P. Clark, M. L. Hamilton, M. Towrie, M. W. George, L. Sun, X. Yang, E. A. Gibson, J. Phys. Chem. C., 2014 DOI: 10.1021/jp4119937

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O-C4-03-04

FISCHER TROPSCH SYNTHESIS – AN EFFECT OF CARBONS

Sarwat Iqbal1*, Thomas E. Davies2, Stuart H. Taylor1, Khalid Karim3, and Graham J. Hutchings1

1Cardiff Catalysis Institute, Cardiff University, Main building park place, Cardiff UK CF10 3AT.2Stephenson Institute for Renewable Energy, Chemistry Dept., Crown Street, Liverpool, UK, L69

7ZD3SABIC T &I, Riyadh, KSA

*Presenting author: [email protected]

Cobalt and iron metal oxides are well known catalysts for the hydrogenation of Carbon monoxide to hydrocarbons. CoMn catalyst prepared by deposition precipitation using different type of carbon support, such as wood carbon and peat derived carbon were studied for their activity in Fischer Tropsch synthesis. A comparison was made with pure CoMnOx catalyst prepared by co-precipitation method.

Type of carbon plays an important role in changing the selectivity pattern especially for CO2, and C+5 hydrocarbons (figure 1). Further an effect of calcination temperature on the surface property of the carbon supported material with respect to activity was established using data obtained from BET, XPS and XRD along with catalyst testing (figure 2).

Figure 1. Effect of carbon types on activity and selectivity for CO hydrogenation Reaction conditions: T = 240°C, CO/H2 = 1:1, P = 6 bar, 5ml/min, Time online = ~60 hours

The activity with respect to CO conversion dropped down along with a decrease in methane and CO2 selectivity, when calcination temperature was increased from 300 to 600°C . An increase in calcination temperature decreased surface area of material, and an abundance of cobalt metal was

observed on surface of catalysts calcined at higher temperature.

Figure 2. Effect of calcination temperature on the Co/Mn/C catalyst

Reaction conditions: T = 240°C, CO/H2 = 1:1, P = 6 bar, 5ml/min, Time online = ~60 hours



1Cardiff Catalysis Institute, Cardiff University, Main building park place, Cardiff UK CF10 3AT. 2Stephenson Institute for Renewable Energy, Chemistry Dept., Crown Street, Liverpool, UK, L69 7ZD 3SABIC T &I, Riyadh, KSA





The activity with respect to CO conversion dropped down along with a decrease in methane and CO2 selectivity, when calcination temperature was increased from 300 to 600°C . An increase in calcination temperature decreased surface area of material, and an abundance of cobalt metal was observed on surface of catalysts calcined at higher temperature.

Figure 2. Effect of calcination temperature on the Co/Mn/C catalyst Reaction conditions: T = 240°C, CO/H2 = 1:1, P = 6 bar, 5ml/min, Time online = ~60 hours

0 10 20 30 40 50 60

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)

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Co/Mn + peat derived carbon Co/Mn + wood derived carbon

0 20 40 60 80

100

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(%) 300°C

400°C 500°C 600°C



1Cardiff Catalysis Institute, Cardiff University, Main building park place, Cardiff UK CF10 3AT. 2Stephenson Institute for Renewable Energy, Chemistry Dept., Crown Street, Liverpool, UK, L69 7ZD 3SABIC T &I, Riyadh, KSA





The activity with respect to CO conversion dropped down along with a decrease in methane and CO2 selectivity, when calcination temperature was increased from 300 to 600°C . An increase in calcination temperature decreased surface area of material, and an abundance of cobalt metal was observed on surface of catalysts calcined at higher temperature.

Figure 2. Effect of calcination temperature on the Co/Mn/C catalyst Reaction conditions: T = 240°C, CO/H2 = 1:1, P = 6 bar, 5ml/min, Time online = ~60 hours

0 10 20 30 40 50 60

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Co/Mn + peat derived carbon Co/Mn + wood derived carbon

0 20 40 60 80

100

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(%) 300°C

400°C 500°C 600°C

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O-C4-03-05

TRIS-HETEROLEPTIC IRIDIUM(III) COMPLEXES FOR WHITE EMISSION

Mr. Yanouk Cudré1, Dr. Etienne Baranoff1

1School of Chemistry, university of Birmingham, B15 2TT, Birmingham, UKPresenting author: [email protected]

Efforts are being made across the energy sector to develop more efficient ways to produce and use energy. As artificial lighting contributes significantly to global energy consumption, a great deal of research is focused on developing low-cost and efficient lighting devices

Organic light-emitting diodes (OLED) and light-emitting electrochemical cells (LEC) are two promising technologies for energy efficient lighting, with one of the major challenges being the development of low-cost white emitting devices. The general approach to obtain white emission is to combine red, green and blue emitters.1 This strategy results in issues, which will be highlighted in this presentation.

Over the years, a large number of phosphorescent iridium complexes have been studied for electroluminescence because of their good stability and excellent photophysical properties such as high quantum yield, short excited state lifetime, and easy tuning of their emitting wavelength.

We will present a strategy for low-cost white electroluminescence, which relies upon a single emitter with a broad emission profile. This approach is based on initial results obtained with an unprecedented broad emitter2 (figure 1, left).

The presentation will focus on one possible method of achieving this goal, namely tris-heteroleptic complexes.3 With three different bidentate ligands, this new family of complexes has the potential to lead to efficient and low-cost white electroluminescence. Synthetic challenges and initial photoluminescent properties will be presented and discussed (figure 1, right).

Figure 1: N966 (left) and its broad emission profiles in solution (red) and in device (black) compared to the standard emitter Ir(ppy)3 (green). New tris-heteroleptic complexes and their synthesis (right).

References1. Zhou, G.; Wong, W.-Y.; Suo, S. J. Photoch. Photobio. C 11, 133 (2010).2. Bolink, H. J.; De Angelis, F.; Baranoff, E.; Klein, C.; Fantacci, S.; Coronado, E.; Sessolo, M.;

Kalyanasundaram, K.; Grätzel, M.; Nazeeruddin, M. K. Chem. Commun, 4672 (2009).3. Baranoff, E.; Curchod, B. F. E.; Frey, J.; Scopelliti, R.; Kessler, F.; Tavernelli, I.; Rothlisberger, U.;

Grätzel, M.; Nazeeruddin, M. K. Inorg. Chem. 51, 215 (2012).

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O-C5-01-02

CONTROLLING COMPETITIVE AND SYNERGISTIC INTERACTIONS IN FORMULATIONS

O.T.Mansour1, B.N.Cattoz1, P.C.Griffiths1, R.K.Heenan2, S.M.King2

1Faculty of Engineering and Science, University of Greenwich, Central Avenue, Chatham, ME4 4TB, UK

2ISIS Neutron and Muon source, Science and Technology Facilities Council, Rutherford Appleton Laboratory, Harwell Oxford, Didcot, OX11 0QX, UK


Amphiphilic block copolymers of the poly (ethylene oxide)–poly (propylene oxide) (PEO–PPO) group (commercially available as Pluronic or Poloxamers) are widely used in numerous applications, especially the pharmaceutical, consumer, technological and formulation areas. Whilst, mixtures of small molecule surfactants and Pluronics have previously been examined, as has the effect of alcohols on Pluronic behaviour. There are far fewer studies of the quaternary systems; Pluronic/small molecule surfactants/alcohol/water.

Against this background, we have employed a range of techniques including surface tension, pulsed gradient spin-echo nuclear magnetic resonance (PGSE-NMR) and small- angle neutron scattering (SANS) to quantify the interaction between these small molecule surfactants (sodium dodecyl sulphate, dodecyltrimethylammonium bromide and polyoxyethylene (23) lauryl ether) and short, medium and long chain alcohols (ethanol, hexanol and decanol respectively) on the critical micelle concentration (CMC) and subsequently the micellar structure. SANS data for aqueous Pluronic solutions with added alcohols fitted to a charged spherical core/shell model for the micelle. The addition of the surfactants led to significantly smaller, oblate elliptical mixed micelles in the absence of alcohols. Addition of ethanol to the system led to a decrease in the micelle size, whereas larger micelles were observed upon addition of longer chain alcohols. NMR studies provided a complementary estimate of the micelle composition using average diffusion coefficients. These observations extend our understanding of the synergistic interactions between the Pluronic and small molecule surfactants when the partitioning of the added alcohol perturbs the interaction between the two types of surfactants.

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O-C5-01-03

Atypical Vesicles Formed by Nonpolar/Polar/Nonpolar Nanoball Amphiphiles

Hung-Yu Chang1, Yu-Jane Sheng1, Heng-Kwong Tsao2

1Department of Chemical Engineering, National Taiwan University, Taipei, Taiwan 106, R.O.C2Department of Chemical and Materials Engineering, Department of Physics, National Central

University, Jhongli, Taiwan 320, R.O.CPresenting author: [email protected]

Fullerene-based amphiphiles are able to form bilayer vesicles in aqueous solution. In this study, the self-assembly behavior of polymer-tethered nanoballs with nonpolar/polar/nonpolar (n-p-n’) motif in a selective solvent is investigated by dissipative particle dynamics. A model nanoball (NB) bears two hydrophobic polymeric arms (n’-part) tethered on an extremely hydrophobic NB (n-part) with hydrophilic patch (p-part) patterned on its surface. Dependent on the hydrophobicity and length of tethered arms, three types of aggregates are exhibited, including NB vesicle, core-shell micelle, and segmented-worm. NB vesicles are developed for a wide range of hydrophobic arm lengths. The presence of tethered arms perturbs the bilayer structure formed by NBs. The structural properties including the order parameter, membrane thickness, and area density of the inner leaflet decrease with increasing the arm length. These results indicate that for NBs with longer arms, the extent of interdigitation in the membrane rises so that the overcrowded arms in the inner corona are relaxed (Figure 1). The transport and mechanical properties are evaluated as well. As the arm length grows, the permeability descends significantly because the steric bulk of tethered arms loosen the packing of NBs. The membrane tension also decreases owing to the increasing reduction of NB/solvent contacts by the polymer corona. Moreover, the size-dependent behavior observed in small liposomes is not significant for NB vesicles due to isotropic geometry of NB. Our simulation results are consistent with the experimental findings [1].

Figure 1: Characteristic morphological snapshots of NB vesicles formed by coarse-grained models with short arms and long arms.

References1. T. Homma, K. Harano, H. Isobe, and E. Nakamura, J. Am. Chem. Soc. 133, 6364 (2011).

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O-C5-01-04

Spatial and Chemical Imaging of the Phillips Ethylene Polymerisation Cr/SiO2 Catalyst using Scanning Transmission X-ray Microscopy

D. Cicmil1, J. Meeuwissen2, B.M. Weckhuysen1

1Inorganic Chemistry and Catalysis, Utrecht University, 3584CG, Utrecht, The Netherlands2Total Research Center Feluy, B-7181, Seneffe, Belgium


The mechanism of oligo/polymerisation of ethylene over Phillips-type Cr/SiO2 catalysts remains poorly understood despite its high importance and extensive use since the 1950s. [1] In our experiments, ethylene polymerisation was studied on a titanated Phillips catalyst, with and without the use of triethylaluminium (TEAl) as the metal alkyl cocatalyst. It is known that titanium enhances the activity of the catalyst material, polymer melt index and molecular weight, while TEAl acts as a reducing agent of chromium and as a scavenger of catalytic poisons. [1]In this work, we have employed the technique of Scanning Transmission X-ray Microscopy (STXM) on a single particle in order to investigate both the catalyst and the polyethylene product formed. [2] Synchrotron radiation provided high brightness and intensity, high collimation, low emittance and wide-energy tunability, which offer high sensitivity, high energy resolution and spatial resolution, which could not be achieved with e.g. UV-Vis or infrared due to the inherent diffraction limitations of this light.During the catalytic reaction, growing polymer fills the pores of the catalyst material causing fragmentation of the particles. [3] Upon fragmentation, different active sites are exposed to the reactant. Titanium is located mostly at, or close to, the surface of the catalyst particle, while chromium is more evenly dispersed (Figure 1). Moreover, several ppm of added TEAl could not reach all of the active sites making this system even more heterogeneous. Due to the presence and distribution of different elements, at least two distinct types of active sites could be linked to the oligomerisation of ethylene and copolymerisation of olefins with ethylene.

Figure 1: (left) 2-D STXM elemental maps of chromium (purple), titanium (blue), polyethylene carbon (green) and epoxy resin carbon (orange), of a Cr/SiO2 catalyst particle after polymerisation of ethylene, as obtained at the 10ID-1 (SM) beamline of the Canadian Light Source CLS; (right) Overlay of elemental maps.

References1. J.P. Hogan, J. Polym. Sci., Part A 8, 2637 (1970); M.P. McDaniel, Adv. Catal. 53, 123 (2010).2. F.M.F. De Groot, E. de Smit, M.M. van Schooneveld, L.R. Aramburo, and B.M. Weckhuysen,

ChemPhysChem 11, 951 (2010)3. X. Zheng, M. Smit, J.C. Chadwick, and J. Loos, Macromolecules 38, 4673 (2005).

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O-C5-01-05

ANIOSOTROPIC HOMOPOLYMER PARTICLES VIA SOLID-STATE POLYCONDENSATIONS

K. Kriechbaum1, D. A. Cerrón Infantes1, M. M. Unterlass1

1Technische Universität Wien, Institute of Materials Chemistry, Getreidemarkt 9, A-1060 Vienna, Austria


Shape-anisotropic or non-spherical particles are of great interest, for example as building blocks of colloidal crystals.[1] Moreover, they are of technological relevance for paints and varnishes due to their behavior in dispersions and at interfaces, which differs considerably from spherical particles.[2] Current preparation techniques of non-spherical homopolymer particles are deformation of initially spherical particles,[3-5] and photopolymerization approaches. [6,7]

We have recently discovered that the solid-state polymerization of monomer salt crystals allows for copying the crystallite shapes without melting or premelting.[8] In the form of a salt, comonomers are preorganized in a crystal, which is made possible by the presence of synthons undergoing strong hydrogen bonding. By engineering the crystallization process, various crystal shapes can be obtained and conserved for the final polymer objects. These shapes range from polyhedral objects to complex roundish mesocrystals. We anticipate our methodology to be a fruitful technique for accessing a considerable range of complex, defined particle shapes.

References1. P. F. Damasceno, M. Engel, S. C. Glotzer, Science 337, 453 (2012). 2. P. J. Yunker, T. Still, M. A. Lohr, A. G. Yodh, Nature 476, 308 (2011). 3. C. C. Ho, A. Keller, J. A. Odell, R. H. Ottewill, Colloid Polym. Sci. 271, 469 (1993).4. J. A. Champion, Y. K. Katare, S. Mitragotri, Proc. Natl. Acad. Sci. U.S.A. 104, 104, 11901 (2007).5. Y. Chevalier, C. Pichot, C. Graillat, M. Joanicot, K. Wong, J. Maquet, P. Lindner, B. Cabane, Colloid Polym. Sci. 270, 806 (1992).6. D. Dendukuri, D. C. Pregibon, J. Collins, T. A. Hatton, P. S. Doyle, Nature Mater. 5, 365 (2006).7. S. Xu et al. Angew. Chem. Int. Ed. 44, 724 (2005).8. M. M. Unterlass, F. Emmerling, M. Antonietti, J. Weber, Chem. Commun. 50, 430 (2014).

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O-C5-02-02

Elucidation of Molecular Characteristics of Renewable and Sustainable Polymers by ab initio Statistical Mechanics

Y. Sasanuma

Department of Applied Chemistry and Biotechnology, Graduate School and Faculty of Engineering, Chiba University, 1-33 Yayoi-cho, Inage-ku, Chiba 263-8522, Japan


In order to comprehend structures, properties, and functions of a given polymer, it is of particular importance, first of all, to elucidate its characteristics features as an isolated chain i.e., molecular characteristics. In our recent studies, conformational characteristics and configurational properties of renewable and sustainable polymers such as poly((R)-3-hydroxybutyrate) (PHB), poly(lactide) (PLA), poly(ethylene succinate) (PES), and poly(butylene succinate) (PBS) have been investigated by density functional and ab initio molecular orbital calculations and NMR experiments on their model compounds and the refined rotational isomeric state scheme [1] for the polymeric chains. The methodology adopted here, designated as ab initio statistical mechanics and previously applied to synthetic aromatic polyesters, poly(ethylene terephthalate) (PET) [2], poly(trimethylene terephthalate) (PTT) [3,4], and poly(butylene terephthalate) (PBT) [4], has been extended to the above-mentioned aliphatic polyesters [5,6].

Our study on PHB [5] has presented not only fully consistent interpretations on its bond conformations, solution properties, crystal structure, thermal properties, and interactions with a PHB depolymerase in terms of its molecular characteristics but also reasonable suggestions as to why PHB is suitable for a biodegradable reserve substance and why only the (R)-enantiomer is permitted to be biodegradable.

The ab initio statistical mechanics, combined with the Bernoulli or Markov stochastic process, has elucidated the molecular characteristics of PLA chains including various configurational sequences to reveal the reason why experimental chain dimensions (i.e., characteristic ratio or radius of gyration) reported so far are considerably scattered and, furthermore, characterize poly(DL-lactide)s synthesized from racemic mixtures of L-lactide and D-lactide with different stereospecific polymerization catalysts [6].

The similar approach has been applied to synthetic biodegradable polyesters, PES and PBS. These symmetric aliphatic polyesters are so flexible as to yield large configurational entropies, as compared with PHB and PLA with a chiral center that restricts the degree of conformational freedom and, consequently, yields small configurational entropies; therefore, PES and PBS show melting points lower than PHB and PLA, whose high melting points may be an outgrowth of the optically-active and sterically-hindered structures necessary for the molecular recognition by the enzymes of bacteria and fungi.

References1. Y. Sasanuma, S. Asai, and R. Kumagai, Macromolecules 40, 3488 (2007).2. Y. Sasanuma, Macromolecules 42, 2854 (2009).3. Y. Sasanuma and N. Suzuki, Macromolecules 42, 7203 (2009).4. Y. Sasanuma, Y. Wagai, N. Suzuki, and D. Abe, Polymer 54, 3904 (2013).5. Y. Sasanuma and S. Katsumata, Polym. J. 45, 727 (2013).6. Y. Sasanuma and D. Touge, Polymer 55, 1901 (2014).

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O-C5-02-03

TOWARDS NEW CELLULOSE ETHERS – SYNTHESIS AND PROPERTIES

C. Goncalves1,2, S. Thiébaud-Roux1,2, C. Cecutti1,2, C. Vaca-Garcia1,2,3, E. Vedrenne1,2.1 INP-ENSIACET, Laboratoire de Chimie Agro-industrielle (LCA), Université de Toulouse, 31030

Toulouse, France2 INRA, UMR 1010 CAI, 31030 Toulouse, France

3 King Abdulaziz University, Jeddah, Saudi ArabiaPresenting author: [email protected]

Cellulose ethers are polymers derived from cellulose that display very interesting properties. Indeed, they can be used as thickeners, binders, films formers, water-retention agents, emulsifiers [1]… Most of the described cellulose ethers are partially or fully substituted with a limited range of functions including carboxyl [2], hydroxyl [3], amine moieties [4] or short chains. They are commonly synthesized using drastic conditions (Williamson reactions, epoxide opening [2]…).In order to broaden the scope of the synthesizable scaffolds and so the scope of the properties of such cellulose ethers, it is thus necessary to develop a new efficient synthetic pathway. This methodology should use mild conditions and respect to the maximum the Twelve Principles of Green Chemistry. In this context, the Suzuki-Miyaura reaction was chosen as it matches most of these criteria [5]. Noteworthy it has never been applied to cellulose derivatives.This pallado-catalyzed reaction involves the coupling of a boron reagent with a halide or a triflate. In order to engage cellulose in a Suzuki-Miyaura (SM) reaction, a first step of functionalization was required to introduce a halide moiety on its scaffold (Scheme 1). The SM reaction was then carried out on the halogenated cellulose to yield a series of new cellulose ethers [6], whose physico-chemical properties were studied.

O

O

O

OO

Br

Br

O

O

O

OO

R

R

Pd(0), base,

additive

(HO)2B

RBr

Br

O

OH

OH

HOO

BrPhCH2Br

NaOH

Key step

Suzuki-Miyauracross-coupling

Scheme 1. Proposed synthesis for new cellulose ethers.

References1. (a) M. Fukasawa, K. Hayakawa, and D. Kuribayashi, US20110091632 A1 (2011); (b) S. C.

Porter. Drug Development and Industrial Pharmacy, 15, 1495 (1989); (c) Y. Wang, and L. Zhang, Biodegradable Polymer Blends and Composites from Renewable Resources (John Wiley & Sons, Inc., New York, pp. 129–161, 2009).

2. H. Thielking, and M. Schmidt, Cellulose Ethers, in: Ullmann’s Encyclopedia of Industrial Chemistry (Wiley-VCH Verlag GmbH & Co. KGaA, New York, 2000).

3. V. Bert and W. Wagenknecht, Macromolecular Symposia, 262, 97 (2008).4. D. Zhang, J. Xie, P.Yu, X. Huang, M. Yang, and H. Liu, Cellulose, 19, 189 (2012).5. V. Polshettiwar, A. Decottignies, C. Len and A. Fihri, ChemSusChem, 3, 502 (2010).6. C. Goncalves, C. Favre, P. Feuardant, S. Klein, C. Vaca-Garcia, C. Cecutti, S. Thiébaud-Roux,

E.Vedrenne, Carbohyd. Polym. DOI 10.1016/j.carbpol.2014.03.089 (2014).

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O-C5-02-04

HIGH PERFORMANCE COPOLY(ESTER-IMIDE)S

S.M. Jones1, S.J. Meehan1, S.W. Sankey2, W.A. MacDonald2, H.M. Colquhoun1.1 Department of Chemistry, University of Reading, Whiteknights, Reading, RG6 6AD, UK

2 DuPont Teijin Films UK Ltd., The Wilton Centre, Redcar, North Yorkshire, TS10 4RF, UKPresenting author: [email protected]

Semi-crystalline aromatic polyesters, notably poly(ethylene terephthalate) (PET) and poly(ethylene-2,6-naphthalate) (PEN), have found widespread use as engineered plastics in film and fibre form due to their high mechanical strength, chemical resistance and dimensional stability [1]. However, the thermal performance of such polyesters is relatively low when compared to other thermoplastic polymers such as polyetheretherketone (PEEK), hence attempts have been made to improve the thermomechanical performance of polyesters by introducing rigid comonomers [2].

Scheme 1: Synthesis of PEN-based copoly(ester-imide)s (2) via melt-polycondensation of bis(2-hydroxyethyl)-2,6-naphthalate with N,N’-bis(2-hydroxyethyl)-biphenyl-3,4,3’,4’-tetracarboxylic diimide (1).

Here we report [3] the novel copolycondensation of N,N-bis(2-hydroxyethyl)-biphenyl-3,4,3’,4’-tetracarboxylic diimide (1) (Scheme 1) with bis(2-hydroxyethyl)-2,6-naphthalate, which has afforded a series of semi-crystalline PEN-based copoly(ester-imide)s (2) displaying enhanced Tgs in comparison to PEN and retention of crystallinity. X-ray powder and fibre diffraction studies have confirmed isomorphic behaviour between the two comonomer repeat units indicating anomalous cocrystallisation within the copolymer series (2). The α-PEN structure is replaced by a new crystal structure when ≥ 5 mol% of (1) is present.

References1. W. A. MacDonald, Polym. Int., 2002, 51, 923.2. J. Xiao, X. Wan, D. Zhang, Q-F. Zhou and S. R. Turner, J. Polym. Sci. Pol. Chem., 2001, 39, 408.3. S. W. Sankey, W. A. MacDonald, D. R. Turner, H. M. Colquhoun and S. J. Meehan, PCT WO

2013/093448 A1, 2013.

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O-C5-02-05

CONTROLLED RAFT POLYMERIZATION AND ZINC BINDING PERFORMANCE OF CATECHOL-INSPIRED HOMOPOLYMERS

A. Isakova1, A. J. Sutherland1, P.D. Topham.1

1 CEAC, Aston University, Aston Triangle, Birmingham, B4 7ET, UKPresenting author: [email protected]

Incorporation of catechols into polymers has long been of interest due to their ability to chelate heavy metals[1] and their use in the design of adhesives[2], metal-polymer nanocomposites[3], antifouling coatings[4], and so on. This work reports, for the first time, the reversible addition-fragmentation chain transfer (RAFT) polymerization of a protected catechol-inspired monomer, 3,4-dimethoxystyrene (DMS), using commercially available trithiocarbonate, 2-(dodecylthiocarbonothioylthio)-2-methylpropionic acid (DDMAT), as a chain transfer agent. Our identified RAFT system produces well-defined polymers across a range of molecular weights (5 kg/mol to 50 kg/mol) with low molar mass dispersities (Ð, Mw/Mn < 1.3). Subsequent facile demethylation of poly(3,4-dimethoxystyrene) (PDMS) yields poly(3,4-dihydroxystyrene) (PDHS), a catechol-bearing polymer, in quantitative yields. Although demonstrating some level of oxidation, PDHS polymers are not cross-linked and remain soluble in various solvents. Semi-quantitative zinc binding capacity analysis of both polymers using SEM/EDXA has demonstrated that both PDMS and PDHS have considerable surface binding (65 % and 87 %, respectively), although the films deposited from PDMS are of a better quality and processability due to solubility and lower processing temperatures (Figure 1).

Figure 1. SEM images of poly(3,4-dimethoxystyrene)-ZnO surface (left) and poly(3,4-dihydroxystyrene)-ZnO surface (right).

References1. J. Bernard, C. Branger, I. Beurroies, R. Denoyel and A. Margaillan, React. Funct. Polym. 72 (2012). 2. G. Westwood, T. N. Horton and J. J. Wilker, Macromolecules 40 (2007). 3. X. W. Fan, L. J. Lin and P. B. Messersmith, Composites Sci. Technol. 66 (2006). 4. S. Heo, Y. Jeon, Y. J. Kim, S. H. Kim and J. Kim, Journal of Coatings Technology and Research 10 (2013).

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O-C5-02-06

Polymerization of Organogold Monomers Giving Highly Regioregular Poly-3-n-hexylthiophene

A. C. J. Heinrich1, A. Staubitz1

1University of Kiel, 24098, Kiel, GermanyPresenting author: [email protected]

Neglected until very recently, the high potential of organogold species in cross coupling reactions have been emerging.1 Organogold compounds can be used as nucleophilic component directly in coupling reactions, but until now, they are only rarely being used.2 We synthesized new aromatic organogold species that can be used as monomers in polymerization reactions to form semiconducting polymers.These monomers contain both a bromine and a gold functional group, potentially allowing for living polymerization reactions. A catalyst screening led to an extraordinary result: While the use of Pd (II) catalysts gave the completely regioirregular P3HT, the use of Pd (0) catalysts gave completely regioregular P3HT without any defects.

S

n-Hex

S

n-Hex

BrPh3PAu

S

n-Hex

S

n-Hex

S

n-Hex

S

n-Hex

SS

n-Hex

n-Hexn

n

Pd (0)

Pd (II)

RR-P3HT

RIR-P3HT

In the talk, the synthesis of these new types of monomers will be discussed as well as the synthesis of the different polymers. A mechanistic proposal will be presented alongside potential applications for this new method for the synthesis of regioregular P3HT.

References1. a) A. Fürstner, P. W. Davis, Angew. Chem. 2007, 119, 3478; Angew. Chem. Int. Ed. 2007, 46, 3410 ; b) A. S. K. Hashmi, Chem. Rev. 2007, 107, 3180 ; c) A. Arcadi, Chem. Rev. 2008, 108, 3266; d) E. Jiménez-Núnez, A. M. Echavarren, Chem. Rev. 2008, 108, 3326; e) Z. G. Li, C. Brouwer, C. He, Chem. Rev. 2008, 108, 3239.2. a) R. Döpp, C. Lothschütz, M. Rudolph, D. Riedel, F. Rominger, A. S. K. Hashmi, Adv. Synth. Catal. 2010, 352, 1307; b) Y. Shi, S. D. Ramgren, S. A. Blum, Organometallics 2009, 28, 1275; c) Y. Shi, S. M. Peterson, W. W. III Haberaecker, S. A. Blum, J. Am. Chem. Soc. 2008, 130, 2168.

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O-C5-02-07

RADICAL POLYMERIZATION UNDER OXYGEN INFLOW – A NEW OPPORTUNITY FOR MACROMOLECULAR DESIGN

Mikhail A. Silant’ev, Sergei A. Kurochkin, Evgeniya O. Perepelitsyna, Vyacheslav P. Grachev

The Institute of Problems of Chemical Physics of the Russian Academy of Sciences,142432, Chernogolovka, Russia


It is well known that the presence of molecular oxygen in the monomer reaction mixture is extremely undesirable. In the case of radical process, oxygen very rapidly reacts with growing radicals to form peroxyl ones. In turn peroxyl radicals participate in all elementary stages of the polymerization and us a result one obtain low rate of polymerization and polymer with peroxide groups. Currently the mechanism of oxidative polymerization is well studied, and we can use high reactivity of oxygen for controlling the length of polymer chains and obtaining of peroxide groups in the backbone.On the example of oxidative polymerization of styrene (AIBN, 95oC), it was shown the feasibility of regulating the length of polymer chain upon variation in the amount of dissolved oxygen [1]. Investigating copolymerization of styrene (St) and divinylbenzene (DVB) under oxygen inflow, we shown dependence of gel-point conversion from [O2] and obtain branched polymer with peroxide groups [2]. The resulting polymers were tested as marcoinitiators in the polymerization of (meth)acrylates with the aim of preparing linear-branched block copolymers (Fig. 1).

Figure 1: Formation of linear-branched block copolymer.

Acknowledgments: This work was supported by a grant of the President of the Russian Federation (16.120.11.2626-MK) and the Russian Foundation for Basic Research (14-03-31997 mol_a).

References1. S.A. Kurochkin, M.A. Silant’ev, E.O. Perepelitsyna, V.P. Grachev, Polymer 54, 31-42 (2013).2. S.A. Kurochkin, M.A. Silant’ev, E.O. Perepelitsyna, V.P. Grachev, Euro. Polym. J., (2014) [In press].

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O-C5-03-02

Polypeptide nanoparticles for ocular drug delivery

A. Dose1, M. A. Caballo-Gonzalez2, S.Hehir1 and N. R. Cameron.1

1Durham University, DH1 3LE, Durham, UK2Complutense University of Madrid, 28040, Madrid, Spain


IntroductionPolypeptides are ideal materials for ocular drug delivery vehicles due to their biocompatibility and biodegradability [1]. Polypeptides of desired molecular weight possessing tunable properties, can be synthesized from amino acid building blocks in a controlled manner using ring opening polymerization (ROP) of N-Carboxyanhydrides (NCAs). Peptide-based nanoparticles were obtained from NCAs containing excellent properties relevant for ocular drug delivery. Polypeptides were synthesized from modified previously described procedures and nanoparticles were prepared either by direct dissolution in water or by the solvent evaporation method [2,3].

Results and DiscussionA series of peptide-based polymers were synthesized via ROP of NCAs, namely block copolypeptides, peptide-hybrid copolymers and photocleavable block copolypeptides. Block copolypeptides based on Bn-glutamate and Z-lysine and photocleavable nitrobenzyl-cysteine NCAs were prepared using trimethylsilyl-protected amines (TMS-amines) as initiators. Peptide-hybrid block copolymers based on Bn-glutamate, alanine and leucine were synthesized from commercially available macroinitiators such as Jeffamine and bis(aminopropyl)poly(ethyleneglycol) (BAPPEG). Self-assembly of the polymers

was achieved by both direct dissolution and solvent evaporation method. The resultant nanoparticles were characterized using DLS and TEM. Stability of the nanoparticles was determined by measurement of the critical micelle concentrations (CMCs), using both fluorescence spectroscopy and DLS. Crosslinking was carried out in order to enhance the stability of the block copolypeptide nanoparticles for use in biological fluids. Further properties relevant to ocular drug delivery applications, such as drug loading with dyes and dexamethasone and corresponding release studies, were also performed. Furthermore, the functionalization of the nanoparticles with the cell penetrating peptide octaarginine will be carried out.

Figure 1: General structure of polymer series and TEM images of nanoparticles ConclusionA series of peptide-based nanoparticles possessing properties relevant for ocular drug delivery have been successfully prepared. Furthermore loading and release studies with dyes and dexamethasone in different concentrations were also performed.References 1. J.V. González-Aramundis, M.V. Lozano, A. Sousa-Hervez, E. Fernandes-Megia, N. Csaba, Expert

Opin on Drug Deliv., 9, p.183-201 (2012).2. H. Lu, J.J. Cheng, J. Am. Chem. Soc., 130, p.12562-12563 (2008).3. H.R. Marsden, L. Gabrielli, A. Kros, Polym. Chem., 1, p.1512-1518 (2010).

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O-C5-03-03

Disruption of Liposomes by Designed pH-Dependent Membrane-Lytic Peptides

A. Kashiwada, J. Hashimoto, M. Mizuno

Department of Applied Molecular Chemistry, Graduate School of Industrial Technology, Nihon University, 275-8575, Narashino, Chiba, Japan


Membrane-lytic peptides with a variety of functions including membrane disruption and self-defense has been used in the form of toxins and antimicrobials. Their functionalities constitute attractive motives for designing novel antibiotics. Moreover, lytic peptide’s sensitivities to biological stimulus are expected to be efficiently utilized in delivery systems. Here, we construct pH-controlled membrane-lytic systems by the use of the peptides designed in

our laboratory. Amino acid sequences of lytic peptides are referred to as Melittin, one of the most investigated lytic peptides, derived from bee venom. Melittin is composed of hydrophobic helix forming segment (residues 4–17) and hydrophilic segment including cationic amino acids (residues 21–26). A typical lytic peptide (LP in Fig. 1) has 26 amino acid residues composed of a helix-promoting hydrophobic segment (Leu-Ala repetitive sequence) and a hydrophilic segment from Melittin. In the presence of liposomes, LP interacts with liposomal surfaces to form a hydrophobic helix in the lipid bilayer [1]. It is considered from the above behavior that LP can perturb the liposomes and exhibit a membrane lytic activity in wide pH range. In order to provide LP with a weakly acidic pH-controlled membrane-lytic activity, we have designed an LPE peptide series (a typical peptide, LPE3-1 is shown in Fig. 1) with hydrophobic segment in which Leu (L) residues are replaced by acidic Glu (E) ones.

Figure 1: Amino acid sequences of membrane-lytic peptides used in this study.

To analyze the membrane-lytic activity of the designed peptides, the leakage assay on calcein-containing small unilamellar EggPC liposomes (lipid concentration: 2.0 mM) was performed. In the event of membrane disruption induced by the pore formation, incorporated calcein would leak from the liposomes to the aqueous surrounding. From the assay in the presence of LP (10 mM) at pH 7.4 and 5.0, leakage of calcein was observed with no pH-dependent profile. On the other hand, LPE3-1 indicated no significant calcein leakage at pH 7.4, but a typical leakage phenomenon was observed at pH 5.0. In order to estimate whether the weakly acidic pH-controlled lytic activity is due to a secondary structural change of hydrophobic segment of LPE3-1 in the liposome membrane, we have measured circular dichroism spectra. In the presence of liposomes, the characteristic alpha-helical minimum at 222 nm was observed only under a weakly acidic condition (pH 5.0). This pH dependence is in agreement with the results from the leakage assay. The pH-dependent membrane disruption properties of the LPE3-1 may open a new avenue to gain an insight into understanding peptide - lipid interaction for the development of efficient drug/gene delivery systems.

Reference1. A. Kashiwada, I. Yamane, M. Tsuboi, S. Ando, and K. Matsuda, Langmuir 28, 2299-2305 (2012).

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O-D1-01-02

Synthesis and Characterization of xMoO3/ZrO2 Based Bifunctional Catalysts for Hydroisomerization

F. F. Oloye, R.P.K. Wells, J.A. Anderson

Department of Chemistry, University of Aberdeen, Aberdeen, Scotland, UK.

[email protected]

In order to improve fuel efficiency, different enhancing agent (such as TEL, MMT etc) had been used, but had now been outlawed by many developed countries. Owing to the stricter laws on enhancing agents, linear alkanes which are abundant in reformate are now converted to iso-alkanes over catalyst. Catalysts such as zeolite based, sulfated zirconia, heteropoly acids, Lewis acids, chlorinated alumina had been tested but all faced with either deactivation, low selectivity to iso-alkanes, expensive or problem of waste disposal [1]. Since reforming and alkylation are faced with challenges such as aromatics and dimers, the only alternative is hydroisomerization. Hydroisomerization over bifunctional catalysts with imbalance acid /metal sites leads to either cracking or production of long isomers of low volatility and low octane number which resulted in low yield and premature catalyst fouling [2].

In this research, zirconia (sulfated and unsulfated) was selected as the support, based on its diversity of physicochemical properties; such as reducing and oxidizing properties, acidic and basic behaviour, thermal resistance capacity [3] and its ability to isomerise linear alkanes at low temperature by providing acid function, while MoO3 was used as the dopant because of its ability to isomerise alkanes which act as the metal site mostly in carbided state. In order to find balance between acidic and metal sites, different amount of MoO3 were impregnated on the supports and calcined at 823 K for 3 h. The effect of MoO3 loadings were investigated using FTIR pyridine adsorption studies to determine nature and strength of acidity; Raman spectroscopy to confirm the loading and the phase of the catalysts; TG-MS to understand the stability of the catalysts and the gases evolved under reaction condition; XRD to know the phase composition; and N2-adsorption-desorption studies at 77 K to know the surface area, pore size and pore volume.

[1] A. Galadima, (2012) Ph.D thesis, university of Aberdeen.

[2] M. Busto, C. Vera, J. Grau, (2011).Fuel Pro. Technol 92:1675-1684.

[3] JC. Yori, CL. Pieck, (2000). Cat. Let. 64:141-146.

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O-D1-01-03

The activity and characterization of flame-made WO3-CeOx-TiO2 catalysts for selective catalytic reduction of NOx by NH3

K.Michalow-Mauke1, Y. Lu2, D. Ferri1, M. Elsener1, K. Kowalski4, T. Graule3, O. Kröcher1,5

1 Paul Scherrer Institute, CH-5232 Villigen, Switzerland2 Lab. Solid State Chemistry and Catalysis, Empa, 8600 Dübendorf, Switzerland

3Lab. High Performance Ceramics, Empa, 8600 Dübendorf, Switzerland4Faculty of Metals Engineering & Industrial Computer Science, AGH University of Science &

Technology,30059 Krakow, Poland5 Institute of Chemical Sciences and Engineering, EPFL, 1015 Lausanne, Switzerland


Nitrogen oxides (NOx) are a major source of air pollution causing photochemical smog and acid rain. Selective catalytic reduction using ammonia (NH3-SCR) is an efficient method to remove NOx. Catalysts based on the V2O5–WO3/TiO2 system are most widely used in the automotive and stationary applications. However, this very effective catalyst system suffers from several drawbacks. Low thermal stability and resulting catalyst deactivation with simultaneous release of toxic vanadium pentoxide to the environment are the most detrimental. Therefore, there is an urgent demand to develop new more thermally stable catalysts, which will be as well cost-effective. In recent years, cerium oxide has attracted considerable attention due to its oxygen storage capacity and the high redox ability of the Ce4+/Ce3+ pair, and is thus successfully utilized in three way catalysts (TWC) and could be as well applied in the SCR catalyst. To present, Ce-W-Ti-oxide based catalysts have been synthesized by wet-chemistry methods. The flame spray synthesis (FSS) is a waste-free method, where nano-powder catalysts can be obtained in a well controllable one-step process. This method allows obtaining unique material composition and hence particle properties due to the high temperature and fast quenching rate in an oxygen-acetylene flame.

A series of WO3-CeOx-TiO2 with 10 wt% WO3 and Ce concentration in the range of 0–20 at% were prepared by FSS. The structural properties of the catalysts were characterized by BET, XRD, HRTEM and HAADF STEM. The specific surface area of as-synthesized nano-powder was around 85 m∙g-1 while TiO2 average particle size was 20 nm. Well crystallized Ti- and Ce-oxide related phases were identified by XRD and confirmed by HRTEM. STEM demonstrated that WO3 forms an amorphous layer over crystalline Ti- and Ce-oxides. XPS revealed that irrespective of catalyst composition Ti and W were in 4+ and 6+ oxidation states, respectively. Ce was mainly in 3+ oxidation state and the fraction of reduced Ce increased with decreasing concentration of Ce reaching 100% in 10 wt% WO3/Ce0.05Ti0.95O2. WO3 enriched the number and the strength of the acid sites. On the contrary, with increasing Ce content the amount of high temperature acid sites progressively decreased. The WO3-CeOx-TiO2 catalysts were tested under NH3-SCR conditions in the 150–450oC temperature range. 10 wt% WO3/Ce0.1Ti0.9O2 showed the best performance, comparable to the well-established V2O5–WO3/TiO2 catalyst. The excellent performance can be related to the high Ce3+ content, which is considered the active site in NH3-SCR, optimal surface acidity and phase composition.

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O-D1-01-04

COOPERATIVE HYDROLYSIS OF ARYL ESTERS ON SOFT INTERFACES

M. Poznik, B. König

University of Regensburg, Faculty of Chemistry and Pharmacy, 93040, Regensburg, GermanyPresenting author: [email protected]

The catalytic hydrolysis of peptides, proteins, phosphates or carboxylate esters plays a crucial role in biological systems. In nature, it is the domain of enzymes, which are efficient, fast and selective. Great effort was put in the synthesis of the hydrolytic catalysts. Artificial hydrolases published so far often mimic the active site of enzymes and contain metal complexes and amino acid residues or moieties similar.1 Their structure and synthesis can be complicated, while the hydrolytic activity is still limited compared to enzymes.

Herein we present an approach that uses fluid membranes of vesicles and micelles as a support for amphiphiles. These are randomly distributed in the bilayer and cooperatively cleave aryl ester bonds (Figure 1).2 The membrane anchored bis-Zn(II)-complex 1 was used as an active center.3 The hydrolytic activity is modified by co-embedded membrane additives which have little or no activity on their own. They represent moieties often appearing in active sites of enzymes.

Figure 1: Concept of cooperative cleavage of fluorescein diacetate on the surface of the vesicular membrane.

With this approach, the hydrolytic activity of the system is enhanced up to 16 fold in comparison to cyclen 1 alone. It is shown that the cooperative hydrolysis is preferred in fluid membranes or micelles, which allow the active moieties to arrange freely. The embedding and dynamic self-assembly of membrane active components in fluid membranes and micelles provides a facile access to hydrolytically active soft interfaces.

References1. Y. Murakami, J.-i. Kikuchi, Y. Hisaeda and O. Hayashida, Chem. Rev. 96, 721-758 (1996).2. M. Poznik, B. König, Org. Biomol. Chem. 12, 3175-3180 (2014)3. B. Gruber, E. Kataev, J. Aschenbrenner, S. Stadlbauer and B. König, J. Am. Chem. Soc. 133, 20704-

20707 (2011).

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O-D1-01-05

Fundamental Sulphur-Chemistry of Molybdenum Carbide: Towards Catalytic Exploitation of Transition Metal Carbides

I. Temprano1, S. J. Jenkins1

1University of Cambridge, UK.Presenting author: [email protected]

The dominant paradigm in the design of heterogeneous catalysts has long been that of reactive pure transition metal (or transition metal alloy) particles dispersed upon an oxide support material. In consequence, decades of effort have resulted in considerable progress towards understanding the principles underlying stability, reactivity and selectivity of important catalytic systems of this basic type, at levels of detail ranging from the chemical engineering perspective to the surface chemistry of individual atoms and molecules. There thus now exists an unbroken chain of knowledge extending from the uhv laboratory to the full-scale chemical plant, and insights from fundamental studies have led to tangible process improvements.

Recently, however, the attention of the heterogeneous catalysis community has increasingly turned towards the range of compounds that are formed by combining transition metals with non-metals other than oxygen. In particular, the transition metal carbides (TMC) have attracted great interest in the last few decades, as their potential for a number of reactions has gradually been recognised and whose chemistry has long been recognised as mimicking that of the noble metals at a fraction of the cost. Furthermore, new routes towards synthesis of these compounds hold the promise of fabricating high-surface-area unsupported catalysts. Moreover, the TMC materials are found not only to display high reactivity and selectivity in a number of reactions, but also to display notable resistance towards poisoning by coke, or by nitrogen- and/or sulphur-containing feedstock. To date, activity of TMC materials in heterogeneous catalysis has been reported in hydroprocessing, ammonia synthesis, water-gas shift, methane conversion to aromatics, hydrogen generation by diesel reforming, and many other reactions beside1, 2. In contrast with the situation pertaining to supported transition metal and/or transition metal alloy particles, however, the extent of fundamental surface science reported on these TMC systems in the literature to date is exceedingly limited.

We present the study of the adsorption and reaction of sulphur-containing molecular species on the surfaces of single-crystal samples of bulk molybdenum carbide, by means primarily of reflection absorption infra-red spectroscopy, Auger electron spectroscopy and thermally programed desorption. The combination of these spectroscopic techniques allows us to extract mechanistic details of the process by which sulphur is removed from organic molecules, and to understand how treatment with hydrogen and hydrocarbons can mitigate the build-up of surface sulphur and prevent catalyst poisoning. Outcomes of this fundamental surface science study will be of interest to the catalysis community, with implications for potential industrial use of molybdenum carbide, and other metal carbides, in applications including not only hydrodesulphurisation of petroleum and biofuel refinery products, but also many other processes such as conversion of methane to aromatics or hydrogen generation by diesel reforming.

References1. H. H. Hwu and J. G. G. Chen, Chem. Rev., 2005, 105, 185.2. A.-M. Alexander and J. S. J. Hargreaves, Chemical Society Reviews, 39, 4388-4401.

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O-D1-01-06

Encapsulation and Catalytic Degradation of the Insecticide Dichlorvos by a Fe4L6 Cage

Jeanne L. Bolliger, Jonathan R. Nitschke

Department of Chemistry, University of Cambridge, Lensfield Road, Cambridge CB2 1EW, United Kingdom


Chiral bis(diimine) ligands (derived from chiral enantiopure diamines and 2-formylpyridine) enantioselectively self-assemble with an iron (II) salt to either the tetrahedral cage molecule DDDD-[Fe4L6]

8+ or its enantiomer, LLLL-[Fe4L6]

8+ (Figure 1) [1,2]. These versatile water-soluble capsules are capable of binding a wide range of organic guests in their large hydrophobic cavities including chiral natural products which form diastereomeric host-guest complexes and can be distinguished by NMR.

Among these guests is also the neurotoxic insecticide dichlorvos, for which the DDDD-[Fe4L6]

8+ coordination capsule serves as a competent supramolecular catalyst for its hydrolysis (Figure 2).Upon reversible encapsulation of dichlorvos into DDDD-[Fe4L6]

8+, catalytic hydrolysis at pH 7 is observed. Dimethyl phosphate (DMP) and dichloroacetaldehyde (hydrate) are detected as major products and dichlorovinyl-methyl phosphate (DVMP) and methanol as minor products.

References1. J. L. Bolliger, A. M. Belenguer, and J. R. Nitschke, Angew. Chem. Int. Ed. 52, 7958 (2013).2. J. L. Bolliger, Chimia 68, 4, 204 (2014).

O

O

OHHO

HOOH

NH2

H2N

*

N

O

12

+ 6

D2O, 12 h, 298

K

FeSO4

Fe2+

Fe2+

O

O OHHO

HOOH

N

N

**

N

NFe2+

Fe2+

∆∆∆∆-[Fe

4L6]8+

*

Fe NN

NN

N

N

∆-FeL3

Figure 1: Subcomponent self-assembly of the DDDD-[Fe4L8]8+.cage.

Cl

ClO

PO

-

O

OMe

-O

POMe

O

OMe

Cl

ClO

POMe

O

OMe

H2O

pH 7

+ MeOH

minor products

H

HO OHCl

Cl

+

major products

DMP

DVMP

Figure 2: Hydrolysis of dichlorvos upon encapsulation.

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O-D1-02-02

Aminopyridine ligands as platforms for well-defined iron water oxidation catalysts and light-driven cobalt reduction catalysts.

J. Lloret-Fillol1

1 Institut de Química Comptacional i Catalisi, Departament de Química,Universitat de Girona, Campus de Montilivi, 17003, Girona, Spain


One of the most appealing research areas is the mechanism understanding of multi-electron multi-proton processes, being central in the activation of small molecules such as the water oxidation to O2 (WO) or reduction to H2 (WR) processes.[1] In this line, we have discovered that readily available iron coordination complexes based on aminopyridine ligands are highly efficient homogeneous WO catalysts.[2-5] We present here one of the few examples of homogeneous and well-defined WO catalysts based on 1st row transition metals, which allows for a mechanistic studies. To gain insight into the mechanism of the Fe-catalyzed WO catalysis, we carried out a detailed study through kinetics, spectroscopic monitoring of intermediates, isotopic effects, isotopic labeling, electronic effects and DFT calculations.[3-5] The roles of the high oxidation state oxo-iron (IV) and (V) and new Fe-O-Ce species in the O-O forming event as well as possible intermediates in the oxidation of organic substrates[5] will be discussed. Likewise, cobalt complexes based on aminopyridine ligands form robust and modular homogeneous catalytic systems for light-driven reductions, in which their electronic and structural properties can be easily tuned.[6] Dynamic Light Scattering (DLS), Nanoparticle Tracking Analysis (NTA) and Hg poisoning studies discarded nanoparticles as active catalytic species. By a combination of experimental and computational studies we have obtained key information about intermediate species and the mechanism for reduction reactions. The mechanism aspects will be discussed in this basis.

References1. V. Artero, M. Fontecave, Chem. Soc. Rev. 42, 2338 (2013). 2. Z. Codolà, M.S.J. Cardoso, B. Royo, M. Costas, J. Lloret-Fillol, Chem. Eur. J, 19, 7203-7213 (2013).3. J. Lloret Fillol, Z. Codolà, I. Gracia Bosch, L. Gómez, J. Pla, M. Costas, Nat. Chem. 3, 807 (2011).4. Z. Codolà, I. Gracia Bosch, F. Acuña, J.M. Lluis, M. Costas, J. Lloret Fillol, Chem. Eur. J. 19, 8042 (2013)5. Z. Codolà, L. Gómez, S.T. Kleespies, L. Que, Jr, M. Costas, J. Lloret-Fillol (submitted) 6. A. Call, Z. Codolà, F. Acuña-Parés, J. Lloret-Fillol Chem. Eur. J. 20, 6171–6183 (2014).

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O-D1-02-03

Development of Ruthenium Tethered Catalysts on Commercial Scale

Vaclav Jurcik,1

1Johnson Matthey Catalysis & Chiral Technologies, 28 Cambridge Science park, Cambridge, CB4 0FP, United Kingdom


Tethered catalysts developed by Wills at el.1 represent evolutionary step of Noyori type transfer hydrogenation catalysts. Due to the tether linking the arene ring to the diamine ligand, the catalysts exhibit enhanced stability and reactivity. Over the recent years, they have been used in a range of transformations towards pharmaceuticals such as antiepileptic drug Eslicarbazepine or anti-asthmatic drug Montelukast.2

RuCl

TsN NH

PhPh

C4-[(R,R)-teth-Ts-Dpen RuCl]

RuCl

TsN NH

PhPh

C3-[(R,R)-teth-Ts-Dpen RuCl]

The presentation will briefly outline the current state of the field of industrial asymmetric hydrogenation and its challenges. In the second part it will describe evolution of C3-[teth-Ts-DPEN RuCl] and C3-[teth-Ms-DPEN RuCl] from academic discovery to commercial product emphasizing importance of robust and cost effective synthesis on scale.3Synthesis, characterization and catalytic activity of a range of novel ruthenium catalysts with 3 and 4 carbon tether and various substituents on the sulphonyl group will also be presented.4Attention will be given to the specific effect of pH on catalytic performance.

In the final part, application of the novel tethered catalysts in synthesis of a selective α1-adrenergic receptor agonist Phenylephrine via transfer hydrogenation will be presented. Newly synthesized tethered catalysts show excellent selectivity at low catalyst loadings. Approaches towards Phenylephrine via pressure hydrogenation and transfer hydrogenation will be compared.

NO

HO .HClN

OHHOTethered catalysts

Et3N/HCOOH

Ph PhHN

OHHO

(R)-Phenylephrine

debenzylation.HCl .HCl

References1. J. Am. Chem. Soc.2005, 7318.2. WO2011131315A1 , WO2009130056A1.3. Adv. Synth. Catal. 2012, 2545.4. Organometallics, submitted.

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O-D1-02-04

EFFICIENT SUZUKI COUPLING IN WATER UNDER MICROWAVE IRRA-DIATIONS, CATALYSED BY PALLADIUM SUPPORTED ON NATURAL

PHOSPHATE

A. Hassine 1,2 - S. Sebti 1 - C. Len 2 - N. Thiebault 2 - A. Fihri 3

1 Laboratory of Organic Chemistry Catalysis and Environment (URAC 17), University of Hassan II Mohammedia-Casablanca, Faculty of Sciences Ben M’Sik, B.P. 7955, 20702 Casablanca, MOROC-

CO. 2 Transformations of Integrated Renewable Material UTC / ESCOM, Royallieu Research Center, BP

20529, F-60205 Compiegne, FRANCE.3 MAScIR Foundation, VARENA Center, Rabat Design, 10100 Rabat, MOROCCO.

e-mail : [email protected]

The carbon-carbon coupling reactions are one of the most important organic reactions because they can develop high value added molecules from relatively simple precursors. These reactions are often cata-lyzed by palladium complexes associated with phosphine ligands in homogeneous medium 1.2. Never-theless, the efficiency of the separation and recycling of the catalyst remains a scientific challenge in the industrial field, which adds cost both economic and environmental processes often prohibitive. These problems can be partly solved by heterogeneous catalysis 3.

In this context, we report a simple and efficient synthesis of natural phosphate-supported palladium heterogeneous catalyst 4 and its excellent application in the Suzuki coupling in water under microwave irradiations.

R1

+

B(OH)2X

R1PdNP

R2 H2O, MWR2

Références[1] A. Fihri, Ph. Meunier, J.-C. Hierso, Coord. Chem. Rev. 2007, 251, 2017.[2] A. F. Littke, G. C. Fu, Angew. Chem. Int. Ed. 2002, 41, 4176.[3] V. Polshettiwar, Len C., A. Fihri, Coord. Chem. Rev2009, 253, 2599-2626. [4] A. Hassine, S. Sebti, A. Solhy, M. Zahouily, C. Len, M.N.Hedhili, A. Fihri, Appl. Catal. A, 2013, 450, 13-18.

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O-D1-02-05

Hairy Catalytic Surfaces – Modular Hybrid Nanostructures for Supported Catalysis

A. E. Fernandes1, Q. Ye1, B. Nysten1, O. Riant1, A. M. Jonas.1

1Institute of Condensed Matter and Nanosciences, Université catholique de Louvain, 1348 Louvain-la-Neuve, Belgium


The control of catalytic properties by molecular design is a central principle in homogeneous catalysis. Nowadays, it is crucial to consider approaches to allow the reuse of such – often complex and expensive synthetic – catalysts. In this aim, the heterogenization of homogeneous catalysts[1] appears particularly suited as considerably simplifying separation and recycling steps. However, it has often proven difficult to maintain the properties of the parent homogeneous catalysts when immobilized. It is hence crucial to interface strategies used in homogeneous and heterogeneous catalysis to design active sites with tailored and sustainable performances.

In this context, we have recently developed polymer brushes as scaffolds for the covalent immobilization of homogeneous palladium catalysts.[2] Here, we describe the application of poly(2-hydroxyethyl methacrylate) (PHEMA) brushes for the immobilization of TBTA-CuCl catalyst. PHEMA brushes were grown on silicon chips by surface-initiated atom-transfer radical polymerization (SI-ATRP)[3] and the side chains further used for the installation of the organometallic complex. The hairy catalyst was investigated in a model CuAAC reaction; key parameters such as grafting density and brush thickness were investigated. Under optimized conditions, the hybrid catalyst demonstrated excellent activity at loadings as low as 0.02 mol%. Future work will focus on transferring our thin catalytic films to the functionalization of microfluidic reactor channels for heterogeneous catalysis.

References1. P. Barbaro, F. Liguori, Heterogenized Homogeneous Catalysis for Fine Chemicals Production

(Springer, Dordrecht, 2010).2. A. E. Fernandes, A. Dirani, C. d’Haese, G. Deumer, W. Guo, P. Hensenne, F. Nahra, X. Laloyaux, V.

Haufroid, B. Nysten, O. Riant, A. M. Jonas, Chem. Eur. J. 18, 16226-16233 (2012).3. R. Barbey, L. Lavanant, D. Paripovic, N. Schüwer, C. Sugnaux, S. Tugulu, H.-A. Klok, Chem. Rev.

109, 5437-5527 (2009).

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O-D1-02-06

THE SELECTIVE OXIDATION OF BIO-DERIVED FURFURAL BY SUP-PORTED GOLD CATALYSTS UNDER MILD CONDITIONS

Mark Douthwaite1, Sarwat Iqbal2, Gemma L. Brett3, Peter J. Miedziak4, Simon A. Kondrat5, Graham J. Hutchings6

1Department of Chemical Engineering, University College London, WC1E 7JE, London, U.K.Presenting author: [email protected]

The emphasis of green chemistry is to satisfy the needs of consumers through methods which are sustainable and economical. Furfural is a toxic and environmentally damaging substrate which is produced in large quantities through the acid hydrolysis of many second generation biological feedstocks1. The majority of research in this area is focussed towards the subsequent hydrogenation of furfural for the production of various fuel additives2, which has left enquiry into its oxidation somewhat unknown. We have discovered that the application of gold supported heterogeneous catalysts with a set of carefully chosen conditions gives approximately 100% selectivity to 2-furoic acid. The catalysts have been heavily characterised with TEM and MP-AES and analysis is conducted by HPLC. This talk will highlight the importance of the support-metal interaction and how it influences both selectivity and conversion. In addition, the mechanistic features of this reaction and promising reusability of the catalyst will also be covered in significant detail.

Figure 1: The selective oxidation of furfural to furoic acid under mild conditions and in the presence of a het-erogeneous catalyst. The catalyst displays very good activity and selectivity to the desired product whilst main-taining a good carbon balance.

References1. V. U. Ambalkar, M. I. Talib, Journal of Engineering, 1, 30-36 (2012).2. J. Lange, E. V D Heide, J. V Buijtenen, R. Price, Chemsuschem, 5, 150 - 166 (2011).

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O-D1-03-02

UNPRECEDENTED HALIDE-FREE ALUMINIUM CATALYST FOR THE SYNTHESIS OF CYCLIC CARBONATES FROM EPOXIDES AND

CARBON DIOXIDE

J. A. Castro-Osma, M. North, X. Wu

Green Chemistry Centre of Excellence, Department of Chemistry, University of YorkYork, UK, YO10 5DD


Carbon dioxide is a cheap, abundant and non-toxic sustainable carbon source for chemical industries. Therefore, the development of new catalytic processes that use carbon dioxide as feedstock has generated great attention in the last few years [1]. Among these processes, the reaction of epoxides 1 and carbon dioxide can afford either polycarbonates 2 or cyclic carbonates 3 and is a 100% atom-economic transformation (Scheme 1). Cyclic carbonates are the thermodynamic product of the reaction and have many applications including as electrolytes for lithium ion batteries, solvents and chemical intermediates [2].

O

R+ CO2

catalyst OO

O

R

catalystO O

R

O

n1

32

Scheme 1: Synthesis of poly – and cyclic carbonates.

Herein, we describe the use of the bimetallic aluminium(salen) complex 4 as a catalyst for the synthesis of cyclic carbonates 3a–3h from terminal epoxides 1a–1h and carbon dioxide under solvent free conditions, at temperatures of 50 to 100 oC, carbon dioxide pressures of 10-50 bar and catalyst concentrations of 0.5-2.5 mol%. Under these conditions the reaction no longer requires a halide cocatalyst such as Bu4NBr, thus avoiding corrosion issues and reducing the cost of production.

1a-h

3a-h

a: R=Me; b: R=Bun; c: R=Octn; d: R=Ph; e: R=4-ClC6H4

f: R=4-BrC6H4; g: R=CH2OH; h: R=PhOCH2

O

R+ CO2

4 (0.5-2.5 mol%) OO

R

O

50–89%50-100 oC, 10-50 bar

N

N

O

O

Al

But

But

But

But

N

N

O

O

Al

But

But

But

But

O

4

Scheme 2: Conversion of epoxides 1a–1h into cyclic carbonates 3a–3h using catalyst 4

References1. M. Aresta, (Ed). Carbon Dioxide as Chemical Feedstock (Wiley-VCH, Weinheim, 2010); M. Aresta,

A. Dibenedetto and A. Angelini, Chem. Rev., 114, 1709 (2014).2. M. North, R. Pasquale and C. Young, Green Chem., 12, 1514 (2010); A. Decortes, A. M. Castilla and

A. W. Kleij, Angew. Chem., Int. Ed., 49, 9822 (2010).

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O-D1-03-03

SELECTIVE HYDROGENATION OF MULTI-UNSATURATED HYDROCARBONS OVER PD: NEW MECHANISTIC INSIGHTS

Swetlana Schauermann, Wiebke Ludwig, Aditya Savara, Karl-Heinz Dostert, Casey P. O‘Brien, Hans-Joachim Freund

Fritz-Haber-Institut der Max-Planck-Gesellschaft, Faradayweg 4-6, 14195 Berlin.Presenting author: [email protected]

Atomistic–level understanding of surface processes is a key prerequisite for rational design of new catalytic and functional materials. In our studies, we investigate mechanisms, kinetics and thermodynamics of heterogeneously catalyzed reactions and adsorption processes on nanostructured model supported catalysts to provide fundamental insights into the surface chemistry. By employing pulsed multi-molecular beam techniques, IRAS and synchrotron-based spectroscopies on Pd/Fe3O4/Pt(111) model surfaces, we study mechanistic details of complex multi-pathway surface reactions, such as hydrocarbon transformation in presence of hydrogen or selective hydrogenation of multi-unsaturated hydrocarbons.

Particularly, we investigate the interaction of α,β-unsaturated ketones isophorone and acrolein and their derivatives on supported Pd nanoparticles and extended Pd(111) surface. It could be shown that the selectivity in hydrogenation of C=O vs. C=C bonds in these compounds critically depends on the chemical composition of the adsorbate overlayers formed on Pd surfaces under the reaction conditions. Thus, selective hydrogenation of C=O bond in acrolein was observed over Pd(111) surface, while only C=C bond hydrogenation could be detected over Pd nanoparticles. These differences in the reactivity can be traces back to the different hydrocarbon spectator species formed in the induction period prior the onset of the product formation. Specifically on Pd(111), acrolein was found to form a dense hydrocarbon layer resulting from partial hydrogenation of the reactant. This layer formed in the induction period serves as a modifier, which renders the surface to be highly selective in C=O bond hydrogenation. On Pd nanoparticles, formation of such hydrocarbon layer is prevented by strong acrolein decomposition and the surface remains active only to hydrogenation of the C=C bond. The underlying mechanistic picture of these surface processes will be discussed.

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O-D1-04-02

Chiral Ferrocenyl-Substituted N-Heterocyclic Carbenes in Asymmetric Catalysis

L. Sigrist, A. Togni.1

1Laboratory of inorganic chemistry, ETH Zurich, Vladimir-Prelog-Weg 2, 8093 Zurich, [email protected]

Starting from Ugi’s amine 1 [1], the chiral ferrocenylimidazole 2 can be obtained in good yield via Ullmann-type coupling. By subjecting 2 to neat alkyl halides such as methyl iodide, the imidazolium salt 3 can be prepared quantitatively. Activation of 3 using silver(I) oxide followed by transmetallation gives rise to the diene precatalysts 4 and 5 (figure 1).

Fe

N

Fe

PhN

NFe

PhN

NI

1 2

Fe

PhN

NMCl

4, M = Rh5, M = Ir

3

Figure 1: Synthesis of the imidazolium salt 3 and application in the complexes 4 and 5

Employing the complexes 4 and 5 in hydrogenation reactions at high pressure forms products in high yield and enantioselectivity (figure 2).

MeOOCCOOMe solvent, 4 h

H2, 10-100 barrt

MeOOC** COOMe

99%, 96%ee

4 / 5 (1 mol%)

Figure 2: Example for the application of 4 and 5 in an enantioselective hydrogenation reaction.

The hydrogenation reactions run without any additives such as e.g. halogen scavengers. Thus, the system is a unique example of a monodentate, phosphane-free catalytic setup, which only requires hydrogen pressure to activate the catalyst. The newest results in the hydrogenation of C-C and C-N double bonds will be presented.

References1. G. W. Gokel, I. K. Ugi, J. Chem. Educ. 1972, 49, 294-296.

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O-D1-04-03

METAL FREE CATALYST FOR CHEMOSELECTIVE METHYLATION OF AMINES USING CO2 AS A METHYLATING AGENT

Shoubhik Das1, Felix D. Bobbink1, Gabor Laurenczy1, Paul J. Dyson*1

École Polytechnique Fédérale De Lausanne (EPFL), CH-1015, Lausanne, SwitzerlandPresenting Author: [email protected]

N-methylation of amines is an important step in the synthesis of many pharmaceuticals and has been widely applied in the synthesis of other key intermediates and chemicals.1 Therefore, the development of efficient methylation methods has continuously attracted attention in recent years. Nevertheless, the most common methylation routes in industry employ toxic agents. Thus, the application of less toxic and more sustainable reagents is highly desired. In this respect, carbon dioxide is an attractive C1 building block because it is an abundant, renewable carbon source.2 Our main aim was to develop a metal free catalytic system which is highly robust and stable, ready availability, inexpensive, and has a low toxicity.

Keeping this in mind, we developed a highly active, metal free catalytic system which operates under mild reaction conditions at atmospheric pressure and at 50°C. These reaction conditions are considerably milder than previous catalytic system known for this reaction and the organocatalyst also tolerates a wide variety of functional groups.3-5 The chemoselective nature of the catalyst is highly attractive for the ‘step-economy’ in the synthesis of pharmaceuticals and fine chemicals. References:1. J. Chatterjee, F. Rechenmacher, H. Kessler, Angew. Chem. Int. Ed. 52, 254 (2013).2. Carbon Dioxide as Chemical Feedstock (Ed.: M. Aresta),Wiley-VCH, Weinheim, (2010).3. Y. Li, X. Fang, K. Junge, M. Beller, Angew. Chem. Int. Ed. 52, 9568 (2013).4. Y. Li, I. Sorribes, T. Yan, K. Junge, M. Beller, Angew. Chem. Int. Ed. 52, 12156 (2013).5. K. Beydoun, T. vom Stein, J. Klankermayer, W. Leitner, Angew. Chem. Int. Ed. 52, 9554 (2013).

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O-D1-04-04

Novel Highly Effective Iron(III) Catalyst for the Synthesis of Cyclic Carbonates from CO2 and Epoxides

Carmine Capacchione1 Assunta De Nisi1, Antonio Buonerba1, Stefano Milione1, Bernhard Rieger2, Alfonso Grassi1

1 Dipartimento di Chimica e Biologia, Università degli Studi di Salerno, Via Giovanni Paolo II - 84084 Fisciano (SA), Italy

2 WACKER Lehrstuhl für Makromolekulare Chemie, Technische Universität München, Lichtenbergstrasse 4, 85748 Garching, Germany


Carbon dioxide is a cheap, non-toxic, abundant and biorenewable resource. The chemical fixation of CO2 by means of its incorporation into chemicals is in the focus of interest of the scientific research. In this area, an important process is the synthesis of cyclic carbonates via the coupling of CO2 and epoxides. Cyclic Carbonates find application as high boiling and polar aprotic solvents, as intermediates in the manufacture of fine chemicals, i.e. as alkylating agents and, through ring opening polymerization, for the synthesis of polycarbonates and polyurethanes. Industrially are obtained from phosgene and diols or by coupling of the CO2 and epoxides under harsh conditions.[1] Homogeneous metal complex catalysts have been introduced effectively for the CO2/epoxide coupling, typically bearing Co(II), Cr(III) or Al(III) as active sites.[2] In spite of its abundance only recently, iron is emerging as a cost-effective and non-toxic metal catalyst. In this work, we reported a novel Fe(III)-based catalyst with a di(thioether)-tris(phenolate) ligand(figure 1), highly effective and selective for the production of cyclic carbonate.

OHS S

OH HO

Figure1 Di(thioether)-tris(phenolate) ligand

Several substrates as propylene oxide, cyclohexene oxide, styrene oxide, epichlorohydrin, allyl glycidyl ether, glycidyl phenyl ether have been tested. To the best of our knowledge, this catalytic system shows the highest TOFs reported among the iron-based catalysts

References1. M. North, R. Pasquale, C. Young, Green Chem. 12, 1514-1539 (2010).2. ) M. Cokoja, C. Bruckmeier, B. Rieger, W. A. Herrmann, F. E. Kühn, Angew. Chem. Int. Ed. 50,

8510-8537 (2011).

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O-D1-04-05

Sunlight-Driven Photocatalytic CO2 Reduction to CH4 by H2 Using Nickel Catalysts

A.V. Puga1, F. Sastre,1 L.C. Liu,1 H. García,1 A. Corma1

1Instituto de Tecnología Química, UPV-CSIC, Valencia, SpainPresenting author: [email protected]

The reduction of carbon dioxide using sunlight as the energy source is a potential solution to both alleviate our dependence from fossil fuels and minimise the greenhouse effects caused by the current atmospheric accumulation of such gas. This strategy would also close the carbon cycle efficiently. In this work, the sunlight-induced reduction of CO2 using H2 as the reducing agent has been studied using a series of n- and p-type semiconductors as potential photocatalysts.

Based on previous research carried out in our laboratories on analogous photocatalytic CO transformations, it was proven that n-type semiconductors are more active for the water gas shift reaction, which entails CO oxidation to CO2 [1], whereas p-type semiconductors catalyse the reduction of CO to CH4, using either H2 or H2O (although to a lesser extent for the latter) as reducing agents [2]. These intriguing results encouraged the investigations presented herein, which showed that CO2 also undergoes efficient reduction to CH4 on p-type semiconductors, being nickel-based materials the most active photocatalysts [3].

Using nanopowdered NiO or Ni/SiO2·Al2O3 photocatalysts, the conversion of CO2 is essentially quantitative under simulated solar light at short reaction times (≤ 1 h). Furthermore, the selectivity to CH4 approaches 100%. Since the reaction is exothermic, the possible effects of local heat evolution on activity could not be overlooked. In this line, dark thermal experiments were conducted and photoactivity spectra were recorded, proving that light absorption by the nickel catalysts is actually initiating the reactions.

Figure 1: Schematic representation of the sunlight-driven photocatalytic reduction of CO2 to CH4 on a nickel-based material, Ni/SiO2·Al2O3 (TEM micrograph shown in the inset).

Regarding the photocatalytic materials, both particle sizes and presence of the silica-alumina support were observed to profoundly affect the reaction outcomes, as will be further detailed in our lecture.

References1. F. Sastre, M. Oteri, A. Corma and H. Garcia, Energy Environ. Sci. 6, 2211 (2013).2. F. Sastre, A. Corma and H. Garcia, Angew. Chem., Int. Ed. 52, 12983 (2013).3. F. Sastre, A.V. Puga, L. Liu, A. Corma and H. García, J. Am. Chem. Soc. 136, 6798 (2014).

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O-D1-04-06

CATALYTIC REDUCTION OF CO2 INTO FORMALDEHYDE UNDER MILD CONDITIONS

A. S. Bontemps

CNRS-LCC, 31077, Toulouse, [email protected]

Functionalization of CO2 is a challenging goal [1] and precedents exist for the generation of HCOOH, CO, CH3OH, and CH4 in mild conditions. In the series of the C1 building blocks used by the industry, CH2O remained to be observed in catalysis. Few years ago we launched a program aimed at evaluating the ability of ruthenium polyhydride complexes to reduce CO2.[2-3] Through the tuning of the catalyst, we are now able to report the direct observation of free formaldehyde from the borane reduction of CO2. Careful analyses of the intermediates and of the catalyst behavior allows us to disclose a complete mechanism. In addition, the selective and efficient synthesis of formaldehyde is achieved by using a reversible trapping strategy.[4]

HBpin + CO2 + pinBOBpin

O

CHH

Ru

PR3

H2HPR3

H2H

Figure 1: Reduction of CO2 into CH2O

References1. M. Cokoja, C. Bruckmeier, B. Rieger, W. A. Herrmann and F. E. Kühn, Angew. Chem., Int. Ed., 50, 8510 (2011).2. S. Bontemps, L. Vendier and S. Sabo-Etienne, Angew. Chem., Int. Ed. 51, 1671 (2012).3. S. Bontemps and S. Sabo-Etienne, Angew. Chem., Int. Ed., 52, 10253 (2013).4. S. Bontemps L. Vendier and S. Sabo-Etienne, J. Am. Chem. Soc. 136, 4419 (2014).

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O-D1-05-02

A New Concept of Catalyst Recycling - Hydroformylation of Long Chain Alkenes in Thermomorphic Solvent Systems

A. Behr, Y. Brunsch, J. Dreimann, M. Zagajewski

Department of Biochemical and Chemical Engineering, Chair of Technical Chemistry, Technical University Dortmund, D-44227 Dortmund, Germany


Hydroformylation, i.e. the homogeneous catalysed reaction of alkenes with synthesis gas yielding aldehydes (and/or alcohols), is the biggest application of homogeneous transition metal catalysis in chemical industry. Since the discovery of this reaction by Otto Roelen 75 years ago different technical processes have been developed based on cobalt or rhodium catalysts. The first cobalt processes had the disadvantage that high temperatures and high pressures (till 300 bar) were necessary. The change to rhodium in the 1970ies afforded the considerable advantage, that only low temperatures, pressures and catalyst concentrations were needed yielding, too, a high n/iso-ratio of the aldehydes. However, rhodium catalysed hydroformylation is limited so far only to short chain alkenes like ethene or propene. In the “Low Pressure Oxo” (LPO) process the aldehydes are separated thermally from the catalyst and in the “Ruhrchemie/Rhone-Poulenc” (RCh/RP) process a separation is possible via an aqueous/organic two phase system. Both separation principles cannot be applied on long chain alkenes: Long chain aldehydes have high boiling points and hence, in the LPO process they cannot be distilled off from the catalyst solution without destroying the rhodium complex. Also the RCh/RP-process can-not be used because long chain alkenes are insoluble in the aqueous catalyst phase. Therefore the indus-trial production of about one million tons/year of long chain aldehydes has to be carried out till now via cobalt catalysis with relatively high investment costs, low regioselectivity and catalyst decomposition in the separation step.

A new concept in homogeneous catalysis is the application of thermomorphic multicomponent solvent (TMS) systems (“tunable solvents”) which was first developed in our group in 1999: During hydroformylation the TMS system is single phase i.e. without any mass transport limitations. After the reaction the temperature is reduced and the TMS system separates into an unpolar organic phase which contains the aldehydes and a polar organic phase which contains the catalyst. When the catalyst phase is recycled a continuously op-erated hydroformylation can be realised (Figure 1).

Figure 1: The principle of TMS systemsIn the present contribution the rhodium catalysed hydroformylation of the model compound 1-do-decene in TMS-systems will be discussed in detail. In laboratory experiments the catalyst, the solvent system and the reaction conditions were optimised and 30 catalyst recycling runs were carried out with success. Then a miniplant was constructed in which the hydroformylation was operated continuously for more than 160 h. Information will be given concerning catalyst activity, selectivity, lifetime and rhodium leaching [1-2].References1. Y. Brunsch, A. Behr, Angew. Chem. Int. Ed., 52, 1586-89 (2013)2. M. Zagajewski, J. Dreimann, A. Behr, Chem. Ing. Tech., 86, (2014), in printThese results were obtained in the framework of the DFG collaborative research centre “InPROMPT”. The authors thank the Federal Ministry of Education and Research for financial support.

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O-D1-05-03

STABLE HETEROLEPTIC ALKALINE-EARTH COMPLEXES: SYNTHESIS AND CATALYSIS OF C–P AND C–N BOND FORMATION

Y. Sarazin1, B. Liu1, S.-C. Roşca1, T. Roisnel1, J-P. Guégan1, J.-F. Carpentier.1

1UMR 6226 CNRS – Université de Rennes 1, 35042 Cedex, Rennes, FrancePresenting author: [email protected]

Means to stabilize complexes of the large, oxophilic alkaline-earth metals (Ae = Ca, Sr and Ba) against ligand scrambling are now available, and as a result the interest in the reactivity of these main group metals is rising sharply. For instance, non-covalent interactions such as Ae···H–Si and Ae···F–C afford stable, yet highly reactive catalysts for polymerization and hydroelementation reactions [1-3].

The preparation of long-sought families of heteroleptic alkaline-earth alkyl and amide complexes will be presented, highlighting the importance of the ligand (aminophenolate, b-diketiminate and imino-anilide) and the role of intramolecular Ae···H–Si agostic bonding towards their stability. The reactivity of the new Ae complexes will be examined in link with four key organic transformations leading to C–P and C–N bond formation: hydrophosphonylation of carbonyls, intermolecular hydroamination and hydrophosphination of activated alkenes, and cyclohydroamination of aminoalkenes [2-6]. The reactions proceed under mild conditions (0-60 °C) and low catalyst loading (0.02-1.00 mol-%), and reaction rates without equivalent are measured. Intermolecular alkene hydroamination and hydrophosphination give strictly anti-Markovnikov products, and the catalytic activity systematically increases with metal size: Ca < Sr < Ba. Key structure-reactivity trends will be scrutinized in light of kinetic and mechanistic investigations.

References1. S.-C. Roşca, T. Roisnel, V. Dorcet, J.-F. Carpentier and Y. Sarazin, under evaluation.2. B. Liu, T. Roisnel, J.-P. Guégan, J.-F. Carpentier and Y. Sarazin, Chem. Eur. J. 18, 6289 (2012).3. B. Liu, T. Roisnel, J.-F. Carpentier and Y. Sarazin, Angew. Chem. Int. Ed. 51, 4943 (2012).4. B. Liu, J.-F. Carpentier and Y. Sarazin, Chem. Eur. J. 18, 13259 (2012).5. B. Liu, T. Roisnel, J.-F. Carpentier and Y. Sarazin, Chem. Eur. J. 19, 2784 (2013).6. B. Liu, T. Roisnel, J.-F. Carpentier and Y. Sarazin, Chem. Eur. J. 19, 13445 (2013).

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O-D1-05-04

A Pd- AND Cu-NHC: A NEW DUAL SYSTEM FOR DIRECT C-H BOND ARYLATION

M. Lesieur1, F. Lazreg1, C. S. J. Cazin.1

1EaStCHEM School of Chemistry, University of St Andrews, KY19 9ST, St Andrews, UK. Presenting author: [email protected]

Together is better: A novel and efficient method for direct C-H bond functionalization of aryls and heteroaryls using well-defined Pd- and Cu-NHC (N-Heterocyclic Carbene) systems has been developed. This process promotes the challenging construction of C-C bonds from arenes or heteroarenes with aryl bromides and chlorides. These Pd- and Cu-NHC complexes display a remarkable stability and a high catalytic activity via intermolecular direct C-H arylation under mild conditions, and without requirement of a directing group. Mechanistic studies evidencing a dual catalytic cycle will be presented.

Ar-Hor

Het-H+ Ar/Het-Ar'Ar'X

PdCu1-2mol%1-3mol%

18 examplesYield (41-98%)

Scheme 1 : Dual catalysis involving Pd- and Cu-NHC system

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O-D1-05-05

CHEMICALS FROM WASTE BIO - OILS

David J. Cole-Hamilton,a* Ruben Duque Garcia,a Ronan le Goff,a Marc Furst,a Juma Mmongoyo,b James Mgaya,b Jennifer Julisa Stuart Bartletta Sabrina Baaderc and Quintino Mganib

a EaStCHEM, School of Chemistry, University of St. Andrews, St. Andrews, Fife, KY16 9ST, Scotland, UK bUniversity of Dar es Salaam, Chemistry Department, P.O.Box 35061, Dar es Salaam, Tanzania

c Fachbereich Chemie, Organische Chemie, TU Kaiserslautern, Erwin-Schrödinger-Straße 54, 67663 Kaiserslautern, GermanyE-mail: [email protected]

As oil supplies dwindle and the price increases, it is essential to find new ways of making the many chemicals on which the quality of our lives depends. One approach is to use renewable resources which can be grown. However, there is a tension between using land for fuel or chemicals production and the need to use land to produce food for the rapidly increasing world population. One possible solution is to use waste products for the manufacture of chemicals. In this presentation, we shall discuss the conversion of methyl oleate and oleic acid, a major component of Tall Oil, a waste from wood processing, into polymer precursors. We shall also discuss the synthesis of a range of important chemicals from cashew nut shell liquid (CNSL), a waste from cashew nut processing.

We shall show how homogeneous carbonylation,[1] metathesis, and reductive amination[2] (see Scheme 1) can be used to make difunctional esters acids, alcohols and amines[1a, 3] for polymer formation[4] (Figure 1).Since homogeneous catalysts suffer the potential difficulty of product-catalyst separation, we shall show how supported ionic liquid phase SILP) catalysts with carbon dioxide flow (see Figure 1) allow the ready separation of the products from the catalyst, thus overcoming one of the major difficulties associated with scaling up and using homogeneous catalysts commercially. We shall describe our developments on metathesis[5] and other reactions using these systems.Cashew nut shell liquid contains interesting phenols meta substituted with an unsaturated C15 chain. We shall described how it can be used to synthesise tse-tse fly attractants, potentially safe detergents, polymer additives, monomers for polymerisation and large ring macrocyclic lactones.[6] (Figure 2.

[1] a) C. Jimenez-Rodriguez, G. R. Eastham, D. J. Cole-Hamilton, Inorg. Chem. Commun. 2005, 8, 878; b) C. J. Rodriguez, D. F. Foster, G. R. Eastham, D. J. Cole-Hamilton, Chem. Commun. 2004, 1720.

[2] A. A. Nunez Magro, G. R. Eastham, D. J. Cole-Hamilton, Chem. Commun. 2007, 3154.[3] a) M. R. L. Furst, R. le Goff, D. Quinzler, S. Mecking, D. J. Cole-Hamilton, Green Chem. 2011, 14, 472; b) M. R. L. Furst, T. Seidensticker, D. J.

Cole-Hamilton, Green Chem. 2013, 15, 1218 [4] a) D. Quinzler, S. Mecking, Angew. Chem. Int. Ed. 2010, 49, 4306; b) F. Stempfle, D. Quinzler, I. Heckler, S. Mecking, Macromol. 2011, 44, 4159.[5] R. Duque, E. Ochsner, H. Clavier, F. Caijo, S. P. Nolan, M. Mauduit, D. J. Cole-Hamilton, Green Chem. 2011, 13, 1187.[6] J. A. Mmongoyo, Q. A. Mgani, J. M. Mdachi, P. J. Pogorzelec, D. J. Cole-Hamilton, Eur. J. Lipid. Sci. Technol. 2012, 114, 1183.




c Fachbereich Chemie, Organische Chemie, TU Kaiserslautern, Erwin-Schrödinger-Straße 54, 67663 Kaiserslautern, Germany

*Tel: +44-1334-463805; Fax: +44-1334-463808; E-mail: [email protected]


We shall show how homogeneous carbonylation,[1] metathesis, and reductive amination[2] (see Scheme 1) can be used to make difunctional esters acids, alcohols and amines[1a, 3] for polymer formation[4] (Figure 1). Since homogeneous catalysts suffer the potential difficulty of product-catalyst separation, we shall show how supported ionic liquid phase SILP) catalysts with carbon dioxide flow (see Figure 1) allow the ready separation of the products from the catalyst, thus overcoming one of the major difficulties associated with scaling up and using homogeneous catalysts commercially. We shall describe our developments on metathesis[5] and other reactions using these systems. Cashew nut shell liquid contains interesting phenols meta substituted with an unsaturated C15 chain. We shall described how it can be used to synthesise tse-tse fly attractants, potentially safe detergents, polymer additives, monomers for polymerisation and large ring macrocyclic lactones.[6] (Figure 2. [1] a) C. Jimenez-Rodriguez, G. R. Eastham, D. J. Cole-Hamilton, Inorg.

Chem. Commun. 2005, 8, 878; b) C. J. Rodriguez, D. F. Foster, G. R. Eastham, D. J. Cole-Hamilton, Chem. Commun. 2004, 1720. [2] A. A. Nunez Magro, G. R. Eastham, D. J. Cole-Hamilton, Chem. Commun. 2007, 3154. [3] a) M. R. L. Furst, R. le Goff, D. Quinzler, S. Mecking, D. J. Cole-Hamilton, Green Chem. 2011, 14, 472; b) M. R. L. Furst, T. Seidensticker, D. J.

Cole-Hamilton, Green Chem. 2013, 15, 1218 [4] a) D. Quinzler, S. Mecking, Angew. Chem. Int. Ed. 2010, 49, 4306; b) F. Stempfle, D. Quinzler, I. Heckler, S. Mecking, Macromol. 2011, 44, 4159. [5] R. Duque, E. Ochsner, H. Clavier, F. Caijo, S. P. Nolan, M. Mauduit, D. J. Cole-Hamilton, Green Chem. 2011, 13, 1187. [6] J. A. Mmongoyo, Q. A. Mgani, J. M. Mdachi, P. J. Pogorzelec, D. J. Cole-Hamilton, Eur. J. Lipid. Sci. Technol. 2012, 114, 1183.

Scheme1. The formation of a range of difunctionalised compounds from methyl oleate using homogeneous catalysis

Fig. 2 Chemicals from cashew nut shell liquid




c Fachbereich Chemie, Organische Chemie, TU Kaiserslautern, Erwin-Schrödinger-Straße 54, 67663 Kaiserslautern, Germany

*Tel: +44-1334-463805; Fax: +44-1334-463808; E-mail: [email protected]


We shall show how homogeneous carbonylation,[1] metathesis, and reductive amination[2] (see Scheme 1) can be used to make difunctional esters acids, alcohols and amines[1a, 3] for polymer formation[4] (Figure 1). Since homogeneous catalysts suffer the potential difficulty of product-catalyst separation, we shall show how supported ionic liquid phase SILP) catalysts with carbon dioxide flow (see Figure 1) allow the ready separation of the products from the catalyst, thus overcoming one of the major difficulties associated with scaling up and using homogeneous catalysts commercially. We shall describe our developments on metathesis[5] and other reactions using these systems. Cashew nut shell liquid contains interesting phenols meta substituted with an unsaturated C15 chain. We shall described how it can be used to synthesise tse-tse fly attractants, potentially safe detergents, polymer additives, monomers for polymerisation and large ring macrocyclic lactones.[6] (Figure 2. [1] a) C. Jimenez-Rodriguez, G. R. Eastham, D. J. Cole-Hamilton, Inorg.

Chem. Commun. 2005, 8, 878; b) C. J. Rodriguez, D. F. Foster, G. R. Eastham, D. J. Cole-Hamilton, Chem. Commun. 2004, 1720. [2] A. A. Nunez Magro, G. R. Eastham, D. J. Cole-Hamilton, Chem. Commun. 2007, 3154. [3] a) M. R. L. Furst, R. le Goff, D. Quinzler, S. Mecking, D. J. Cole-Hamilton, Green Chem. 2011, 14, 472; b) M. R. L. Furst, T. Seidensticker, D. J.

Cole-Hamilton, Green Chem. 2013, 15, 1218 [4] a) D. Quinzler, S. Mecking, Angew. Chem. Int. Ed. 2010, 49, 4306; b) F. Stempfle, D. Quinzler, I. Heckler, S. Mecking, Macromol. 2011, 44, 4159. [5] R. Duque, E. Ochsner, H. Clavier, F. Caijo, S. P. Nolan, M. Mauduit, D. J. Cole-Hamilton, Green Chem. 2011, 13, 1187. [6] J. A. Mmongoyo, Q. A. Mgani, J. M. Mdachi, P. J. Pogorzelec, D. J. Cole-Hamilton, Eur. J. Lipid. Sci. Technol. 2012, 114, 1183.

Scheme1. The formation of a range of difunctionalised compounds from methyl oleate using homogeneous catalysis

Fig. 2 Chemicals from cashew nut shell liquid

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O-D1-05-06

Green oxidation of Glycerol to value added chemicals over supported Phosphotungstate

A. Patel 1, S. Singh 1

1 Polyoxometalate and Catalysis Laboratory, Department of Chemistry, Faculty of Science, The M. S. University of Baroda, Vadodara 390 002, Gujarat, INDIA


The increasing abundance of glycerol, its renewability, and attractive pricing make this product an appealing platform molecule to derive a family of commercially value added chemical. Significant efforts have been devoted to the transformation of glycerol by various catalytic processes [1]. Especially, selective oxidation of glycerol is of particular interest due to the commercial importance of oxygenated glycerol derivatives such as, glyceraldehyde, dihydroxyacetone, glyceric acid, glycolic acid and others [2]. Heterogeneous catalysts play a key role in the promotion and control of such reactions. Supported polyoxometalates are one of the excellent candidates for the same.

Figure 1: Glycerol oxidation over supported phosphotungstate

In the present work Phosphotungstates supported to different supports were synthesized and characterized by various physicochemical techniques. The catalytic activity was evaluated for oxidation of glycerol with molecular oxygen and hydrogen peroxide. The conditions for maximum conversion as well as selectivity for desired Dihydroxyacetone and Glyceraldehyde were optimized by varying different parameters. In this work, the combination of both high performance and selectivity to Dihydroxyacetone and Glyceraldehyde was successfully achieved. The selectivity’s of the products obtained could be due to the combination of the nature of the catalyst, pore structure of support, and to a great extent by experimental conditions. The catalysts were recycled up to four cycles in order to test their activity as well as stability. References1. M. Pagliaro, M. Rossi, The Future of Glycerol, (2nd Edition, RSC Green Chemistry Series-8, 2010).2. S. Gil, M. Marchena, L. S. Silva, A. Romero, P. Sanchez, J. L. Valverde, Chem. Eng. J. 178, 423-435 (2011).

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O-D2-01-02

LOW-COORDINATE TRANSITION METAL TERPHENYL COMPLEXES: NOVEL STRUCTURES AND REACTIVIES

T. J. Blundell, B. M. Gridley, D. L. Kays, H. R. Sharpe.

School of Chemistry, University of Nottingham, University Park, Nottingham, NG7 2RD, U.K.Presenting author: [email protected]

The use of sterically demanding aryl ligands allows the isolation of highly unsaturated transition metal complexes which often show unusual bonding modes and reactivity [1]. Use of the bulky m-terphenyl ligand 2,6-Mes2C6H3

- (Mes = 2,4,6-Me3C6H2) has allowed the isolation of (2,6-Mes2C6H3)2M (M = Mn, Fe, Co 1); rare two-coordinate transition metal aryls [2]. In comparison, the use of the naphthyl-substituted ligands 2,6-Naph2C6H3

- (Naph = 1-C10H7) generally affords three-coordinate complexes (e.g. 2), where the substituents confer considerable steric bulk and as a result of limited conformational flexibility introduce multiple conformations to these systems [3]. Calculations confirm the results of spectroscopic measurements which indicate several conformational isomers in solution.Reactions between (2,6-Mes2C6H3)2Co or (2,6-Naph2C6H3)2Co(OEt2) and dry carbon monoxide yield a highly encumbered benzophenone featuring bulky terphenyl moieties and a terphenyl-substituted keto-fluorenone (3), respectively [4]. These unusual products are formed through M−C bond breaking and C–C bond forming reactions, affording new stereocentres in the reaction products. Conversely, the reaction between (2,6-Pmp2C6H3)2Co (Pmp = 2,3,4,5,6-Me5C6) and CO yields acyl (2,6-Pmp2C6H3)COCo(CO)4 and diketone [(2,6-Pmp2C6H3)CO]2. Furthermore, recent results utilising main group substrates are facilitating access to cluster complexes not accessible through conventional synthetic routes. Modification of the aryl substituents allows tailoring of the steric pocket in which the metal centre is encapsulated; even subtle ligand changes affords significant modification of chemical reactivity.

Figure 1: Two- and three-coordinate complexes (1 and 2) and a keto-fluroenone (3) with two new stereocentres formed by multiple M−C bond breaking and C–C bond forming reactions.

References1. D. L. Kays, Dalton Trans. 40, 769 (2011).2. D. L. Kays (née Coombs) and A. R. Cowley, Chem. Commun. 1053 (2007).3. B. M. Gridley, G. J. Moxey, W. Lewis, A. J. Blake and D. L. Kays, Chem. Eur. J. 19, 11446 (2013).4. B. M. Gridley, A. J. Blake, A. L. Davis, W. Lewis G. J. Moxey and D. L. Kays, Chem. Commun. 48,

8910 (2012).

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O-D2-01-03

Studies on Copper Amides and Lithium Amidocuprates: Important Intermediates in Synthetic Bond Forming Protocols

R. P. Davies1

1 Department of Chemistry, Imperial College London, SW7 2AZ, London, UKPresenting author: [email protected]

The low cost, versatile reactivity and low environmental impact of copper has made it an attractive target for incorporation into the next generation of milder and greener catalytic processes. Organocopper species in particular are already known to play key roles in a number of carbon-carbon and carbon-heteroatom bond forming reactions. These include catalytic processes (such as Ullmann condensation) as well as stoichiometric reactions (for example Gilman conjugate addition). However, it is only relatively recently that significant insights have been obtained into the mechanism of operation of these species and the origin of their unique reactivity.[1] One of the first steps in building current understanding of organocopper species has been the identification of the structural forms adopted by these complex systems in both the solid state and solution.[1-2] This structural and mechanistic information is crucial for allowing rational design of more robust systems.

We report here upon the structure and reactivity of a series of novel copper-amides (CuNR2) and amidocuprates [CuR(NR’2)]

- and explore their role in bond-forming mechanisms. Thus, the aggregation states of copper amides (CuNR2) in solution has been investigated with the aid of 1H DOSY NMR spectroscopy, and the interaction of these aggregates with ancillary ligands including 1,10-phenathroline probed. In addition the structural isomers of a number of lithium heteroamidocuprates LiCuR(NR’2) have been studied, with the steric and electronic properties of the amido group (NR’2) shown to significantly influence the solid-state structures and the position of the solution equilibrium (see Figure below).[3]

References1. R. P. Davies, Coord. Chem. Rev. 255, 1226 (2011)2. R. Bomparola, R. P. Davies, S. Lal, A. J. P. White, Organometallics, 31, 7877 (2012)3. R. Bomparola, R. P. Davies, S. Hornauer, A. J. P. White, Dalton Trans. in press (2014)

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O-D2-01-04

AMIDO AND ALKYL COMPLEXES OF CALCIUM AND STRONTIUM CONTAINING HIGHLY FLUORINATED Tp’ LIGANDS

N. Romero,1,2 C. Dinoi,1,2 M. Etienne.1,2

1 CNRS; LCC (Laboratoire de Chimie de Coordination); BP 44099; 205 route de Narbonne, 31077, Toulouse, France.

2 Université de Toulouse; UPS, INPT; LCC; F-31077 Toulouse, FrancePresenting author: [email protected]

The chemistry for the heavier group 2 metals (Ae) is underdeveloped. The main challenge of this chemistry is to control the Schlenk equilibrium that scrambles the ligands in heteroleptic complexes (2 AeXX’ = AeX2 + AeX’2). Several heteroleptic complexes {L}Ae-Nu (L = b-diketiminate; tris(pyrazolyl)borates, etc.;[1] Nu = NR2, OR) proved to be good catalysts in ROP and hydroelementation reactions. Few examples of heteroleptic alkyl complexes are known.[2]

Highly fluorinated hydrotris(indazolyl)borate proligands TpF with tunable electronic and steric properties have been developed in our group.[3] We describe herein our initial attempts at unravelling the chemistry of TpFAe complexes. The very electron poor ligand F21-Tp4Bo,CF3 failed to coordinate to Ca2+, whereas adding two equiv. of Tl(F12-Tp4Bo,Ph) to CaI2 gave the homoleptic [(F12-Tp4Bo,Ph*)2Ca] with a sterically induced 1,2-borotropic shift in the ligand.[4]

The heteroleptic amido complexes [(F12-Tp4Bo,Ph)AeNR2] (Ae = Ca, Sr; R = SiMe3, SiMe2H) were synthesized. Agostic distortions, especially strong for Sr, stabilize the structures (Figure 1). [(F12-Tp4Bo,Ph)Ca{N(SiMe3)2}] is a very active catalyst for the cyclohydroamination reaction. The rare heteroleptic alkyl complexes [(F12-Tp4Bo,Ph)CaR] (R = CH(SiMe3)2, C≡CPh) have also been characterized.

SrN

NF

F

FF

N N

F

FF

F

B

NN

F F

F

F

H

N

Si

Si

CaN

NF

F

FF

N N

F

FF

F

B

NN

F F

F

F

H

N

Si

SiSr

N N

F

FF

F

B

NN

F F

F

F

H

N

Si

Si

Figure 1: [(F12-Tp4Bo,Ph)Ae{N(SiMe3)2}] (Ae = Ca, Sr) complexes.References1. S. Harder, Chem Rev. 110, 3852 (2010).2. M. Arrowsmith, M. S. Hill, G. Kociok-Kohn, Organomet. 33, 206, (2014).3. (a) B. K. Muñoz, W.-S. Ojo, K. Jacob, N. Romero, L. Vendier, E. Despagnet-Ayoub and M. Etienne, New J. Chem. DOI:10.1039/C4NJ00136B (2014). (b) W.-S. Ojo, K. Jacob, E. Despagnet-Ayoub, B. K. Muñoz, S. Gonell, L. Vendier, V.-H. Nguyen, M. Etienne, Inorg. Chem. 51, 2893 (2012).4. N. Romero, L. Vendier, C. Dinoi, M. Etienne, Dalton Trans. DOI : 10.1039/C4DT00884G, (2014).

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O-D2-02-02

Direct Observation of Two-Electron Ag(I)/Ag(III) Redox Cycles in Coupling Catalysis

M. Font1, F. Acuña-Parés1, T. Parella2, J. Serra, J. M. Luis, J. Lloret-Fillol, M. Costas, X. Ribas1Institut de Química Computacional i Catàlisi (IQCC) and Departament de Química, Universitat de

Girona, Campus Montilivi, E-17071, Girona, Catalonia (Spain)2Servei de RMN, Facultat de Ciències, Universitat Autònoma de Barcelona, Campus UAB, E-08193,

Bellaterra, Catalonia (Spain)Presenting author: [email protected]

Silver holds the most unexplored chemistry among the coinage metals and its redox chemistry is the least understood [1]. Two-electron redox catalytic cycles, which are most common in noble metal organometallic reactivity, have never been considered. Herein we show that an unprecedented Ag(I)/Ag(III) catalytic cycle is operative in model C-O and C-C cross-coupling reactions. An aryl-Ag(III) species has been unequivocally identified as intermediate in the catalytic cycle and we provide direct evidences of aryl halide oxidative addition and C-O, C-N, C-S, C-C and C-halide bond-forming reductive elimination steps at monometallic silver centers. We anticipate our study as the starting point for expanding Ag(I)/Ag(III) redox chemistry into new methodologies for organic synthesis, resembling well-known copper or palladium cross-coupling catalysis. Furthermore, findings described herein provide unique fundamental mechanistic understanding on Ag-catalyzed cross-coupling reactions and dismiss the generally accepted conception that silver redox chemistry can only arise from one electron processes.

X

AgIII

NucNuc

via aryl-AgIII species+

AgI cat.

XRD

-2e-

Nuc

Oxidativeaddition

+2e-

Reductiveelimination2+

References1 a S. K. Hashmi, Silver in Organic Chemistry (Ed. M. Harmata), Ch. 12, 357-379 (John Wiley &

Sons, Hoboken, 2010). b J. –M. Weibel, A. Blanc, P. Pale, Chem. Rev. 108, 3174-3173.2. M. Font, F. Acuña-Parés, T. Parella, J. Serra, J. M. Luis, J. Lloret-Fillol, M. Costas, X. Ribas, submitted.

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O-D2-02-03

Iron(I) Compounds in an Unusual Coordination Geometry: Initiators for Dehydrogenation of Ammonia Boranes

C. Lichtenberg,1 L. Viciu,1 M. Adelhardt,2 J. Sutter,2 K. Meyer,2 H. Grützmacher1

1 Laboratory of Inorganic Chemistry, ETH Zuerich, 8093, Zuerich, Switzerland2 Department of Inorganic Chemistry, Friedrich-Alexander-University Erlangen-Nuremberg, 91058,

Erlangen, GermanyPresenting author: [email protected]

The discovery of an Fe(II)Fe(I) system in the active center of [FeFe]-hydrogenases has spurred the interest in catalytically active Fe(I) species.[1] However, reports on homogenous Fe(I) catalysis are rare, as catalytically active Fe(I) species can be difficult to isolate. Examples include olefin hydrogenation,[2a] coupling of arylazides to give diazo compounds,[2b] and C–C coupling reactions.[2c] We report the first heterobimetallic Fe(I) amide compounds 1 and 2. They show an unusual[3] (distorted) square planar coordination geometry around Fe as shown by single crystal X-ray analysis and confirmed by SQUID magnetometry. Unexpectedly, compounds 1 and 2 display clearly distinct Mössbauer parameters in spite of their structural similarity. Thus, the choice of the counter ion [Na(thf)3]

+ vs. [Li(OEt2)2]

+ indirectly affects the properties of the Fe center.

N N

Fe

Nathf

thf thf

N N

Fe

LiEt2O OEt2

1 2

≡

Figure 1: Cutout of molecular structure of 1 and Lewis drawings of compounds 1 and 2.

The catalyzed dehydrogenation of ammonia boranes is of interest in material science, in organic synthesis, and as a means of on-demand H2 generation.[4] Very recently it was shown that Fe catalysts mostly operate under heterogeneous conditions in these reactions with only a single known exception.[4] Compounds 1 and 2 catalyze the dehydrogenation of Me2HNBH3 (equation 1). No indications for heterogeneous catalysis were found in these reactions. Catalyst 1 is significantly more active revealing a remarkable counter ion effect. The catalytic activity of 1 is also higher than that of the only known evidently homogeneous Fe catalyst for this transformation.

Me2HN BH3

Me2NH2B

BH2

NMe2

5 mol% 1 or 2

0.5 +

H2

[1] C. Tard, C. J. Pickett, Chem. Rev. 109, 2245 (2009).[2] (a) J. C. Peters et al., Organometallics 32, 3053 (2013); (b) J. C. Peters et al., J. Am. Chem. Soc.

132, 4083 (2010); (c) R. B. Bedford et al., J. Am. Chem. Soc. 134, 10333 (2012).[3] P. L. Holland et al., J. Am. Chem. Soc. 128, 756 (2006).[4] I. Manners et al., J. Am. Chem. Soc 136, 3048 (2014).

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O-D2-02-04

SELECTIVE REDUCTION OF CARBOXYLIC ACIDS DERIVATIVES CATALYZED BY IRON AND MANGANESE COMPLEXES

J. Zheng, L. C. Misal Castro, H. Li, C. Darcel, J.-B. Sortais

Université Rennes 1, Institut des Sciences Chimiques de Rennes, UMR 6226, Centre for Catalysis and Green Chemistry, 263 Avenue du Général Leclerc, Rennes, 35046, FRANCE


Aldehydes are key building blocks in organic synthesis due to their high reactivity and are valuable compounds in flavour and fragrance industry. Among the various methods developed for the preparation of aldehydes, the direct reduction of carboxylic acids and carboxylic esters to aldehydes is a straightforward reaction, which usually suffers from selectivity issues due to the over-reduction to alcohols. During the last years, hydrosilylation has emerged as an elegant and efficient methodology for the reduction of carboxylic acid derivatives under mild conditions with high chemoselectivity. Lately, the selective hydrosilylations of carboxylic acids to form aldehydes have been developped: we have employed an iron catalyst, namely (PBO)Fe(CO)3, (PBO = trans-4-phenyl-but-3-en-2-one) combined with 1,1-3,3-tetramethyldisiloxane[1] and Mn2(CO)10 with Et3SiH.[2] In parallel, the chemoselective reduction of esters to aldehydes using N-heterocyclic carbene iron complexes such as (IMes)Fe(CO)4 as the catalyst in the presence of secondary silanes (diethylsilane or diphenylsilane) as the reducing agent was also investigated.[3] In the three cases, the formation of in situ stable disilylacetals intermediates, converted into aldehydes upon hydrolysis, allows the transformation to proceed with high chemoselectivity.

COOH7 6

CHO7 6or

Mn2(CO)10 HSiEt3

UV (350 nm)

Fe(CO)3OPh

Me2SiHOSiHMe2, 50 °C

CO2MeMeO2C11

CHOOHC11Et2SiH2

UV (350 nm)

N

NMes

Mes

Fe(CO)4

Figure 1: Selective reduction of oleic acid and di-esters to aldehydes with hydrosilanes

References1. L. C. Misal Castro, H. Li, J.-B. Sortais and C. Darcel, Chem. Commun., 48, 10514 (2012).2. J. Zheng, S. Chevance, C. Darcel and J. B. Sortais, Chem. Commun., 49, 10010 (2013).3. H. Li, L. C. Misal Castro, J. Zheng, T. Roisnel, V. Dorcet, J.-B. Sortais and C. Darcel, Angew. Chem. Int. Ed., 52, 8045 (2013).

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O-D2-02-05

A METHANDIIDE AS NON-INNOCENT LIGAND IN RUTHENIUM CARBENE COMPLEXES

J. Becker, V.H. Gessner

Institute of Inorganic Chemistry, University of Wuerzburg, 97074, Wuerzburg, Germany [email protected]

Due to the application of geminal dianions in the synthesis of carbene complexes, such dilithi-ated systems have become subject of extensive research over the past two decades. Carbene com-plexes formed from geminal dianions differ from the well-known and widely used Fischer- and Schrock-type carbene complexes and thus present a new class of carbene species. Here, the met-al carbon bond is formally formed by a four-electron-donation from the ligand to the metal core.[1,2,3] In this context, bis(iminophosphorano) and bis(thiophosphoryl)methandiides have gained special interest as they are rare examples of readily available geminal dianions.

Concerning the question whether the α-susbtituent electronically influences the metal carbon bond, our group is currently exploring the chemistry of sulfonyl substituted geminal dianions. One example is the dimetalated species 1-Li2,

[4] which cleanly reacts via salt metathesis with [Ru(L)Cl2]2 (L = p-cymene) to ruthenium carbene complex 2. Here we show that the carbene ligand in 2 acts as a non-innocent ligand allowing for metal ligand cooperativity in a variety of different E-H bond activation reactions (Fig. 1). Furthermore, complex 2 can be applied as a catalyst in transferhydrogenation reactions, making use of the non-innocent behavior of the carbene ligand.[5]

Figure 1: a) Synthesis and reactivity of ruthenium carbene complex 2; b) molecular structure of 2.

References1. T. Cantat, N. Mézailles, A. Auffrant, P. Le Floch, Dalton Trans. 15, 1957 (2008).2. S. Harder, Coord. Chem. Rev. 11-12, 1252 (2011). 3. V. H. Gessner, F. Meier, D. Uhrich, M. Kaupp, Chem. Eur. J. 19, 16729 (2013). 4. P. Schröter, V. H. Gessner, Chem. Eur. J. 18, 11223 (2012); J. Becker, V.H. Gessner, Organometallics

33, 1310 (2014); J. Becker, V. H. Gessner, Dalton Trans. 43, 4320 (2014).5. J. Becker, V. H. Gessner, manuscript submitted.

PPhPh

SS

Ph

O O

Li Li

1-Li2

[Ru(L)Cl2]2

L=p-cymene

rt, toluene

2

H2 R-OH

a) b)

PPh

Ph

S

SPh

OO

Ru

PPh

Ph

S

SPh

OO

Ru

H

OR

3 4 5

E-H activation H-H

activation O-H activation

R =

C6H5 p-C6H4OMe

p-C6H4CF3

E-H

E =

SiR3 NR2

PPh

Ph

S

SPh

OO

Ru

H

HP

PhPh

S

SPh

OO

Ru

H

E

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O-D2-02-06

Single-Electron Reactivity on Late Transition Metals Mediated by Redox-active Ligands

Danny L.J. Broere, Bas de Bruin, Joost N.H. Reek, Jarl Ivar van der Vlugt* Van ‘t Hoff Institute for Molecular Sciences, Faculty of Science,

University of Amsterdam, Science Park 904, 1098 XH Amsterdam, The Netherlands

Redox-active ligands can induce noble metal reactivity upon base metals by acting as an electron reservoir. [1-4] However, establishing radical-type reactivity with noble metals using a redox-active ligand is far less explored. A new redox-active tridentate ligand has been designed and coordinated to palladium. A paramagnetic palladium complex has been isolated (S = ½) which can undergo reversible one-electron oxidation and reduction. Using a combination of experimental and computation methods it is established that the unpaired electron predominantly resides on the ligand. Interestingly, this un-paired electron can be transferred to a bound substrate which can subsequently react in a radical type fashion. This exciting feature has been exploited to convert alkyl azides into pyrrolidines via a radical pathway, which is very uncommon with Pd(II).[5]

[1] Wieghardt, K and Chirik, P., Science 327 (2010) 794-795.[2] Ward, T.R. et al., Angew. Chem. Int. Ed. 51 (2012) 10228-10234.[3] Dzik, W.I.; van der Vlugt, J.I.; Reek, J.N.H.; de Bruin, B. Angew. Chem. Int. Ed. 50 (2011)

3356-3358.[4] van der Vlugt, J.I., Eur. J. Inorg. Chem. (2012) 363-375.[5] Broere, D.L.J.; de Bruin, B.; Reek, J.N.H.; Lutz, M.; Dechert, S.; van der Vlugt, J.I. submitted

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O-D2-03-02

CHAMELEON BEHAVIOR OF A PHOSPHINE-ALANE FLP UPON COORDINATION

M. Devillard1, G. Bouhadir1, E. Nicolas2, C. Slootweg2, W. Uhl3, D. Bourissou.1

1Université de Toulouse, UPS, LHFA, 118 route de Narbonne, 31062 Toulouse, France2Department of Chemistry and Pharmaceutical Sciences, VU University Amsterdam, De Boelelaan

1083, 1081 HV Amsterdam, The Netherlands.3Institut für Anorganische und Analytische Chemie der Westfälischen Wilhelms-Universität Münster,

Corrensstrasse 30, 48149 Münster, [email protected]

Frustrated Lewis Pairs (FLP) have recently attracted huge interest, in particular for the metal-free ac-tivation of small molecules such as H2, CO2…. Their ability to coordinate metal fragments and engage into original metal/ligand interactions has also been evidenced, in particular with phosphine-boranes.1 Comparatively, complexes of phosphine-alanes remain scarce.2 In this work, we have explored the co-ordination chemistry of compound 13 in which the phosphine and alane moieties are ideally positioned to cooperatively interact with a metal fragment. Different original coordination modes were authenti-cated: (i) bridging P→M–Cl→Al coordination, (ii) chloride transfer from the metal to aluminum lead-ing zwitterionic complexes, (iii) bridging P→M→Al coordination (despite the associated ring strain), involving the alane as σ-acceptor ligand. The spectroscopic, structural and computational studies of representative phosphine-alanes complexes will be discussed.

Bridged coordination:

P M Cl Al

Al

P

Ph

Au L

Cl AlR'2

PR2

Ph Al

P

PhR'2

R2

Cl

[M]

Al

P

Ph

[M]

Abstraction of chloride:Zwitterionic complexes

P M Al

L-Au-Cl

L =

tht or PMe3

[M]-Cl

[M] =

Rh(nbd)

Pd(allyl)R2

R2

R'2

R'2

R =

Mes, R' =

tBu

R'2Al as σ -acceptor ligand:

[M] =

Au-C6F5, Au-CCPh

or

Pt(PPh3)

[M]

phosphine-alane 1

or

References1. For general reviews see: G. Bouhadir, A. Amgoune and D. Bourissou, Adv. Organomet. Chem. 58, 1

(2010). A. Amgoune and D. Bourissou, Chem. Commun. 47, 859 (2011).2. M. Sircoglou, G. Bouhadir, N. Saffon, K. Miqueu and D. Bourissou Organometallics 27, 1675

(2008). M. Sircoglou, N. Saffon, K. Miqueu, G. Bouhadir and D. Bourissou, Organometallics 27, 6780 (2013).

3. C. Appelt, H. Westenberg, F. Bertini, A. W. Ehlers, J. C. Slootweg, K. Lammertsma and W. Uhl, Angew. Chem. Int. Ed. 50, 3925 (2011).

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O-D2-03-03

Alkyllithium Adducts with Stereochemically Pure Aminomethoxysilanes Involved: Mechanistic Insight into Stereocontrolled Substitutions at Silicon

J. O. Bauer, C. Strohmann

TU Dortmund, D-44227, Dortmund, GermanyPresenting author: [email protected]

After we had discovered a new highly stereoselective and convenient route to silicon-stereogenic nitrogen-oxygen-functionalized organosilanes containing R2N–Si–OMe structural motifs [1,2], we were yet able to reveal an unprecedented coordination behavior of a chiral aminomethoxysilane with tBuLi [3]. In this presentation, we will focus on stereochemically pure N,O-functionalized silanes that form low molecular adducts comprising a silicon-based N,O-ligand and an alkyllithium compound. In each case, a silicon-bound methoxy group participates in complex formation. This will guide us to interesting mechanistic considerations for metal-mediated stereocontrolled substitution reactions taking place at aminomethoxy-silanes on the basis of experimental and theoretical investigations (Figure 1).

NR2∗

Si∗

MeOR2

R1

NR2∗

SiMeO

OMeR1

R2Li

MECHANISM ?

A B

Figure 1: Stereo-determining nucleophilic attack of an organolithium compound at a silicon center.

References1. J. O. Bauer, C. Strohmann, Angew. Chem. 126, 738 (2014); Angew. Chem. Int. Ed. 53, 720 (2014).2. J. O. Bauer, C. Strohmann, Chem. Commun. 48, 7212 (2012).3. J. O. Bauer, C. Strohmann, Angew. Chem. DOI: 10.1002/ange.201404255; Angew. Chem. Int. Ed.

DOI: 10.1002/anie.201404255.

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O-D2-03-04

MAIN-GROUP METAL PRECATALYSTS FOR THE RING-OPENING POLYMERIZATION OF CYCLIC ESTERS:

SYNTHESIS, MECHANISMS AND KINETIC ANALYSIS

Y. Sarazin1, J.-F. Carpentier1, M. Bochmann.2

1UMR 6226 CNRS – Université de Rennes 1, 35042 Cedex, Rennes, France2University of East Anglia, NR4 7TJ, Norwich, United Kingdom


New homogenous precatalysts built on metals from groups 2 (Ca-Ba), 13 (Al-In) and 14 (Ge-Pb) for the ring-opening polymerization (ROP) of green cyclic esters such as lactide (LA) has enabled us to prepare a range of polyesters with improved properties, and to investigate the relevant mechanisms. We endeavor to develop processes that meet industrial criteria, notably through controlled immortal ROP reactions using exogenous alcohol as a transfer agent.

Several phenolate-based ligands and strategies for the stabilization of robust ROP precatalysts will be introduced. Their performances in the ROP of cyclic esters will be explored. Novel Al–In chiral complexes producing highly isotactic polylactide from racemic LA will be presented, and the nature of the pertaining mechanisms will be debated [1-5].

New insight into both living and immortal ROP mechanisms gained from DFT calculations and 119Sn NMR spectroscopy will also be discussed. A kinetic model for controlled ROP reactions based on first principles will be introduced. It can be applied to any catalyst for the ROP of any monomer, and gives an immediate measure of the propagation (kp) and initiation (ki) rate constants. For immortal ROP, it takes the exchange rate constant (ke) into account. The model will be illustrated here with industrially pertinent tin(II) ROP precatalysts [5-7].

[metal] OR

M

[metal] M OR

ROHRO-M-H

k i

ke

M = monomer (LA, TMC

.....)

ROH = alcohol

chain transfer agent

k i =

initiation rate constant

ke = alcohol

exchange rate constant

kp =

propagation rate constantkp

M

References1. N. Maudoux, T. Roisnel, V. Dorcet, J.-F. Carpentier and Y. Sarazin, Chem. Eur. J. doi: 10.1002/

chem.201304788 (2014).2. Y. Sarazin, B. Liu, T. Roisnel, L. Maron and J.-F. Carpentier, J. Am. Chem. Soc. 133, 9069 (2011).3. B. Liu, T. Roisnel, J.-P. Guégan, J.-F. Carpentier and Y. Sarazin, Chem. Eur. J. 18, 6289 (2012).4. B. Liu, T. Roisnel, L. Maron, J.-F. Carpentier and Y. Sarazin, Chem. Eur. J. 19, 3986 (2013).5. V. Poirier, T. Roisnel, S. Sinbandhit, M. Bochmann, J.-F. Carpentier and Y. Sarazin, Chem. Eur. J.

18, 2998 (2012).6. L. Wang, C. E. Kefalidis, S. Sinbandhit, V. Dorcet, J.-F. Carpentier, L. Maron and Y. Sarazin, Chem.

Eur. J. 19, 13463 (2013).7. L. Wang, V. Poirier, F. Ghiotto, M. Bochmann, R. D. Cannon, J.-F. Carpentier and Y. Sarazin,

Macromolecules 47, 2574 (2014).

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O-D2-03-05

Synthesis and characterization of novel phosphastannapropenic derivatives

Petronela M. Petrar, Raluca Şeptelean, Gabriela Nemeş

Facultatea de Chimie și Inginerie Chimică, Universitatea Babeș-Bolyai, 11, Arany Janos Street, RO-400028, Cluj-Napoca, Romania


Phosphastannapropenes containing the –P=C-Sn< moiety are very scarcely reported in the literature, but their structure suggests that they can be of interest as precursors of inorganic materials, and their potential catalitic activity is worth investigating. They are also precursors of heavy phosphaallenes of the type -P=C=E< (E= group 14 elements), which have been evidenced so far only for E = C, Si and Ge [1-3].Several new phosphastannapropenes were synthesized starting from the dichlorophosphaalkene Mes*P=CCl2 (Mes*=2,4,6-tri-tertbutyl-phenyl) and dichlorotin derivatives following the synthetic route described in scheme 1.

Mes*P=CCl2+

R2SnCl2+

nBuLi-78oC- nBuCl

Mes*P=C

Cl

Li Mes*P C

Cl

SnR2

Cl- LiCl

-90oC

R2SnCl2 = Me2SnCl2

, nBu2SnCl2, Ph2SnCl2

,Sn

ClCl

Scheme 1

The compounds were characterized by multinuclear NMR spectroscopy and single-crystal X- ray diffraction, where suitable crystals have been obtained. A preliminary study of their reactivity will be discussed, with an emphasis on the behavior towards lithium derivatives; as such reactions could lead to heavy heteroallenes.

References1. J. Escudié, H. Ranaivonjatovo and L. Rigon, Chem. Rev. 100, 3639 (2000).2. J. Escudié and H. Ranaivonjatovo, Organometallics 26, 1542 (2007).3. J. Escudié and G. Nemes, C.R. Chimie 13, 954 (2010).

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O-D2-03-06

Striking Reactivity of Novel Silyliumylidene Cations

Shigeyoshi Inoue

Institut für Chemie, Technische Universität Berlin, Strasse des 17. Juni 135, D-10623, Berlin, Germany

Shigeyoshi Inoue: [email protected]

Silylium ions [R3Si+] have been of significant interest to a wide range of chemists because of their interesting property and strong Lewis acidity. The use of silylium ions in catalysis is currently enjoying growing interest. On the other hand, silylenes [R2Si:] have attracted much attention in past 20 years and are now enjoying their interesting reactivities and potential applications in transition metal catalysis. With this in mind, we developed the design, synthesis, characterization and reactivity investigation of novel silylenes utilizing functional groups such as hydridosilylene,[1] iminosilylene,[2] and phosphinosilylene[3]. Despite the recent dramatic progress in the chemistry of silylium ion and silylene, the chemistry of silyliumylidene ion [RSi:+] is largely unexplored. Although some examples of silyliumylidene ions employing the well-designed bidentate chelate ligand and combination of two different N-heterocyclic carbenes were synthesized,[4,5] it is still challenging to isolate of such a positively charged, electron-deficient, low-coordinate silicon compound. In this contribution, we report a convenient synthetic strategy to access silyliumylidene ions 1 using two N-heterocyclic carbenes starting from the corresponding dichlorosilane (Scheme 1).[6] Reaction of silyliumylidene ion 1 with three equivalents of phenylacetylenes yields the 1-alkenyl-1,1-dialkynylsilane 2 through the C-H activation of the terminal alkynes. Interestingly, 1 easily reacts with CO2 or N2O at room temperature to give a silacarboxylate derivative 3 as its dimer form. Moreover, 1 easily reacts with S8 at room temperature to give a cationic silanethione 4 with Si=S double bond.

Si

N

N

Cl

N

N - Me4NHC HCl

HPh

- 2 Me4NHC

3 Si

HH

1

CO2 or N2O

SiSi

O

OO

O

N N

H

NN

H

23

- Me4NHC

Scheme 1. Synthesis and reactivity of novel silyliumylidene ions

References1. S. Inoue, C. Eisenhut, J. Am. Chem. Soc. 2013, 135, 18315.2. S. Inoue, K. Leszczyńska, Angew. Chem. Int. Ed. 2012, 51, 8593.3. S. Inoue, W. Wang, C. Präsang, M. Asay, E. Irran, M. Driess J. Am. Chem. Soc. 2011, 133, 2868.4. Y. Xiong, S. Yao, S. Inoue, E. Irran, M. Driess, Angew. Chem. Int. Ed., 2012, 51, 10074.5. Y. Xiong, S. Yao, S. Inoue, J. D. Epping, M. Driess, Angew. Chem. Int. Ed., 2013, 52, 7147.6. S. U. Ahmad, T. Szilvási, S. Inoue, submitted.

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O-D2-04-02

The Potentiality of High Valent Metal Halides of Groups 5-6 in the Activation of Organic Molecules

Marco Bortoluzzi1, Mohammad Hayatifar2, Fabio Marchetti2, Guido Pampaloni2, Calogero Pinzino3, Stefano Zacchini4

1 Ca’ Foscari University of Venice, Dipartimento di Scienze Molecolari e Nanosistemi Dorsoduro 2137, I-30123 Venezia, Italy

2 University of Pisa, Dipartimento di Chimica e Chimica Industriale, Via Risorgimento 35, I-56126 Pisa, Italy

3 ICCOM-CNR UOS Pisa, Research Area, Via Moruzzi 1, I-56124 Pisa, Italy4 University of Bologna, Dipartimento di Chimica Industriale “Toso Montanari”, Viale Risorgimento

4, I-40136 Bologna, [email protected], http://www.dcci.unipi.it/~fabmar

NbF5, NbCl5 and WCl6 are easily-available compounds, whose direct interaction with organic reactants was scarcely explored up to recent years. Our investigation on this piece of chemistry has provided evidence of unusual features: 1) the cited halides are capable of directing mild conditions transformations, which are not commonly achieved by means of other transition metal compounds [1]; 2) NbF5, NbCl5 and WCl6 can act as one-electron oxidants towards a variety of organic molecules, resulting in the formation of salts containing reactive cations [2]; 3) such salts may be stabilized by inert, high valent metal haloanions which are generated in situ. Examples will be provided with reference to natural a-aminoacids (see Figure 1), alkoxy-arenes, alkyl-ureas and amines.

Figure 1: possible activation pathways of L-proline by reactions with NbCl5 and WCl6.

References1. (a) F. Marchetti and G. Pampaloni, Chem. Commun., 48, 635 (2012); (b) M. Bortoluzzi, F. Marchetti, G. Pampaloni and S. Zacchini, Inorg. Chem., 53, 3832 (2014).2. F. Marchetti, G. Pampaloni, C. Pinzino and S. Zacchini, Angew. Chem. Int. Ed., 49, 5368 (2010).

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d-/f-Block Heterobimetallic N-Heterocyclic Carbene Complexes.

Andrew A. Fyfe1 and Polly L. Arnold.1

1 EaStChem School of Chemistry, University of Edinburgh, West Mains Road, Edinburgh, EH9 [email protected]

Our research focuses on f-block N-heterocyclic carbene (NHC) complexes and their reactivity towards small molecules. We have developed anionically tethered NHC ligands which enable the soft carbene to be retained within the coordination sphere of the hard f-metal centre [1]. It is this weak hard/soft interaction that lead us to the idea of using these bidentate ligands to bridge between two metal fragments. Such complexes are of interest as the cooperative effect between the two metals can lead to chemistry that is very different to that of the corresponding monometallic complex [2]-[4]. To this end, the novel Fe(II)-U(IV) heterobimetallic NHC complex 1, figure 1, has been synthesised from the homoleptic, monometallic iron (II) species Fe(LMes)2 and the U(IV) metallacycle (N″)2U[{N(SiMe3)Si(Me2)CH2}] (LMes =OC(Me2)CH2(1-C{NCH2CH2NMes}); Mes = 2,4,6-Me3C6H2; N″ = N(SiMe3)2). The reactivity of 1 with a range of small molecules such as isonitriles, alcohols and carbon monoxide has been investigated.

References1. P. L. Arnold, I. J. Casely, Z. R. Turner and C. D. Carmichael, Chem. Eu. J., 2008, 14, 10415.2. B. P. Greenwood, S. I. Forman, G. T. Rowe. C-H. Cheng, B. F. Foxman and C. M. Thomas, Inorg.

Chem., 2009, 48, 6251.3. S. Kuppuswamy, T. M. Powers, J. P Krogman, M. W. Bezpalko, B. M. Foxman and C. M. Thomas,

Chem. Sci., 2013, 4, 3557.4. A. P. Sobaczynski, T. Bauer and R. Kempe, Organometallics, 2012, 32, 1363.

d-/f-Block Heterobimetallic N-Heterocyclic Carbene Complexes.

Andrew A. Fyfe1 and Polly L. Arnold.1

1 EaStChem School of Chemistry, University of Edinburgh, West Mains Road, Edinburgh, EH9 3JJ [email protected]

Our research focuses on f-block N-heterocyclic carbene (NHC) complexes and their reactivity towards small molecules. We have developed anionically tethered NHC ligands which enable the soft carbene to be retained within the coordination sphere of the hard f-metal centre [1]. It is this weak hard/soft interaction that lead us to the idea of using these bidentate ligands to bridge between two metal fragments. Such complexes are of interest as the cooperative effect between the two metals can lead to chemistry that is very different to that of the corresponding monometallic complex [2]-[4]. To this end, the novel Fe(II)-U(IV) heterobimetallic NHC complex 1, figure 1, has been synthesised from the homoleptic, monometallic iron (II) species Fe(LMes)2 and the U(IV) metallacycle (N″)2U[{N(SiMe3)Si(Me2)CH2}] (LMes =OC(Me2)CH2(1-C{NCH2CH2NMes}); Mes = 2,4,6-Me3C6H2; N″ = N(SiMe3)2). The reactivity of 1 with a range of small molecules such as isonitriles, alcohols and carbon monoxide has been investigated.

References 1. P. L. Arnold, I. J. Casely, Z. R. Turner and C. D. Carmichael, Chem. Eu. J., 2008, 14, 10415. 2. B. P. Greenwood, S. I. Forman, G. T. Rowe. C-H. Cheng, B. F. Foxman and C. M. Thomas,

Inorg. Chem., 2009, 48, 6251. 3. S. Kuppuswamy, T. M. Powers, J. P Krogman, M. W. Bezpalko, B. M. Foxman and C. M.

Thomas, Chem. Sci., 2013, 4, 3557. 4. A. P. Sobaczynski, T. Bauer and R. Kempe, Organometallics, 2012, 32, 1363.

Fe

U

1 1

Figure 1: Crystal structure and ChemDraw of Fe-U complex 1. Some methyl groups and a mesityl group have been omitted for clarity in the crystal structure.

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O-D2-04-04

CAGE-LIKE METALLASILSESQUIOXANES: SYNTHESIS, COMPLEXATION REACTIONS AND COORDINATION POLYMERS

CREATION

A.N. Bilyachenko1, A.A. Korlyukov1, A.I. Yalymov1, M.M. Levitsky1

1Nesmeyanov Institute of RAS, 119991, Moscow, [email protected]

Cage-like metallasilsesquioxanes attract much attention from different scientific teams worldwide due to their extraordinary molecular architecture and potential application (e.g. in homo- and heterogeneous catalysis) [1]. Recently we elaborated a new approach to such compounds, based on partial cleavage of polymeric coppersilsesquioxane followed by controlled assembly of cage products [2].Now we present new frontiers of this approach – successful isolation and characterisation of Mn(II)-, Co(II)- and Ni(II)-containing silsesquioxane cages. Also, some discussion will be given on specific reactivity of Cu(II)-silsesquioxane towards N- and P-containing ligands (fig. 1). Several ways of design of coordination polymers on such cage’ basis will be presented.

Figure 1: Tetranuclear Mn(II),Na-silsesquioxane (left); binuclear Ni(II),Na-silsesquioxane (center); complex of hexanuclear Cu(II)-silsesquioxane with phenanthroline (right)

References1. (a) M.M. Levitsky, B.G. Zavin and A.N. Bilyachenko, Russ. Chem. Rev., 76 (9), 847 (2007); (b) R. Murugavel, A. Voigt, M.G. Walawalkar and H.W. Roesky, Chem. Rev., 96, 2205 (1996); (c) A.J. Ward, A.F. Masters and T. Maschmeyer, Adv. Silicon Sci., 135 (2011).2. (a) A.N. Bilyachenko, M.S. Dronova, A.I. Yalymov, A.A. Korlyukov, L.S. Shul’pina, D.E. Arkhipov, E.S. Shubina, M.M. Levitsky, A.D. Kirilin and G.B. Shul’pin, Eur. J. Inorg. Chem., 5240 (2013); (b) M.S. Dronova, A.N. Bilyachenko, A.I. Yalymov, Y.N. Kozlov, L.S. Shul’pina, A.A. Korlyukov, D.E. Arkhipov, M.M. Levitsky, E.S. Shubina and G.B. Shul’pin, Dalton Trans., 43, 872 (2014).

This work was supported by RFBR (projects 14-03-31772 and 14-03-00713) and Council of the President of the Russian Federation MD-3589.2014.3

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O-D2-04-05

DFT AND DEVICE MODELLING RESULTS IN MOLECULAR OXIDE BASED ELECTRONIC DEVICES

L. Vilà-Nadal1, C. Busche1, J. Yan1, H. N. Miras1, D.-L. Long1, V. P. Georgiev2, A. Asenov2, R. H. Pedersen2, N. Gadegaard2, M. M. Mirza2, D. J. Paul2, J. M. Poblet3, L. Cronin.*1

1WestCHEM, School of Chemistry, The University of Glasgow, Glasgow G12 8QQ, UK2School of Engineering, The University of Glasgow, Glasgow G12 8LT, UK

3Departament de Química Física i Inorgànica, Universitat Rovira i Virgili, c/Marcel·lí Domingo s/n, 43007 Tarragona, Spain


Polyoxometalates (POMs) [1] are an outstanding family of com-pounds, well known for their huge structural diversity [2], inter-esting catalytic activities [3] and rich electrochemistry. POMs are comprised of metal oxide building blocks with a general formula {MOx}n, where M= Mo, W, V, and sometimes Nb and x=3-7 . The embedding of tetrahedral ([SO4]2-, [PO4]3-, [SiO4]4-), oc-tahedral ([IO6]5-, [TeO6]6-) or pyramidal ([SO3]2-, [BiO3]3-) anions in the POM structure leads to the subfamily of heteropoly-oxometalates (HPOMs). The idea of molecular electronics was first postulated in 1974 when Ari Aviram and Mark Ratner of IBM speculated about organic molecules as components in electronic circuits. They proposed turning individual molecules into circuit components in order to build computers from the bottom up ap-proach. From an engineering perspective, however, organic mo-lecular electronics raises questions of high resistance and power, low performance and problematic fabrication, reproducibility and reliability: we have resolved these issues by using POM molecules that are better-matched to SiO2 substrate. By means of a muldi-disciplinary approach: density functional theory (DFT), chemical synthesis, device modeling and nanoscale device fabrication; we propose to use an HPOM as a na-noscale molecular memory element.

References1. M. T. Pope., Heteropoly and Isopoly Oxometalates (Springer-Verlag, New York, 1983).2. a) A. Müller, and S. Roy, Coord. Chem. Rev. 245, 153-166 (2003). b) A. Müller, P. Kögerler, and C. Kuhlmann, Chem. Commun., 1347-1658 (1999).3. W. B. Kim, T. Voitl, G. J. Rodríguez-Rivera, S. T. Evans, and J. A. Dumesic, Angew. Chem. Int. Ed. 44, 778-792 (2005).

DFT AND DEVICE MODELLING RESULTS IN MOLECULAR OXIDE BASED

ELECTRONIC DEVICES

L. Vilà-Nadal1, C. Busche1, J. Yan1, H. N. Miras1, D.-L. Long1, V. P. Georgiev2, A. Asenov2,




Polyoxometalates (POMs) [1] are an outstanding family of compounds, well known for their huge structural diversity [2], interesting catalytic activities [3] and rich electrochemistry. POMs are comprised of metal oxide building blocks with a general formula {MOx}n, where M= Mo, W, V, and sometimes Nb and x=3-7 . The embedding of tetrahedral ([SO4]2-, [PO4]3-

, [SiO4]4-), octahedral ([IO6]5-, [TeO6]6-) or pyramidal ([SO3]2-, [BiO3]3-) anions in the POM structure leads to the subfamily of heteropolyoxometalates (HPOMs). The idea of molecular electronics was first postulated in 1974 when Ari Aviram and Mark Ratner of IBM speculated about organic molecules as components in electronic circuits. They proposed turning individual molecules into circuit components in order to build computers from the bottom up approach. From an engineering perspective, however, organic molecular electronics raises questions of high resistance and power, low performance and problematic fabrication, reproducibility and reliability: we have resolved these issues by using POM molecules that are better-matched to SiO2 substrate. By means of a muldidisciplinary approach: density functional theory (DFT), chemical synthesis, device modeling and nanoscale device fabrication; we propose to use an HPOM as a nanoscale molecular memory element. References 1. M. T. Pope., Heteropoly and Isopoly Oxometalates (Springer-Verlag, New York, 1983). 2. a) A. ll , and S. Roy, Coord. Chem. Rev. 245, 153-166 (2003). b) A. ll , P. Kög l , and C. Kuhlmann, Chem. Commun., 1347-1658 (1999). 3. W. B. Kim, T. Voitl, G. J. Rod ígu z-Rivera, S. T. Evans, and J. A. Dumesic, Angew. Chem. Int. Ed. 44, 778-792 (2005).

Figure 1: A schematic diagram representation of a single-transistor non-volatile memory cell, indicating the aimed substitution of the poly-Si floating gate (FG) with an array of polyoxometalate clusters (POM layer).

Figure 2: Graphical representation comparing the HOMO–LUMO gap in eV for [W18O54(SO4)2]4- (left) and (right) Wells-Dawson anion [W18O54 (SO3)2]4-.

DFT AND DEVICE MODELLING RESULTS IN MOLECULAR OXIDE BASED

ELECTRONIC DEVICES

L. Vilà-Nadal1, C. Busche1, J. Yan1, H. N. Miras1, D.-L. Long1, V. P. Georgiev2, A. Asenov2,




Polyoxometalates (POMs) [1] are an outstanding family of compounds, well known for their huge structural diversity [2], interesting catalytic activities [3] and rich electrochemistry. POMs are comprised of metal oxide building blocks with a general formula {MOx}n, where M= Mo, W, V, and sometimes Nb and x=3-7 . The embedding of tetrahedral ([SO4]2-, [PO4]3-

, [SiO4]4-), octahedral ([IO6]5-, [TeO6]6-) or pyramidal ([SO3]2-, [BiO3]3-) anions in the POM structure leads to the subfamily of heteropolyoxometalates (HPOMs). The idea of molecular electronics was first postulated in 1974 when Ari Aviram and Mark Ratner of IBM speculated about organic molecules as components in electronic circuits. They proposed turning individual molecules into circuit components in order to build computers from the bottom up approach. From an engineering perspective, however, organic molecular electronics raises questions of high resistance and power, low performance and problematic fabrication, reproducibility and reliability: we have resolved these issues by using POM molecules that are better-matched to SiO2 substrate. By means of a muldidisciplinary approach: density functional theory (DFT), chemical synthesis, device modeling and nanoscale device fabrication; we propose to use an HPOM as a nanoscale molecular memory element. References 1. M. T. Pope., Heteropoly and Isopoly Oxometalates (Springer-Verlag, New York, 1983). 2. a) A. ll , and S. Roy, Coord. Chem. Rev. 245, 153-166 (2003). b) A. ll , P. Kög l , and C. Kuhlmann, Chem. Commun., 1347-1658 (1999). 3. W. B. Kim, T. Voitl, G. J. Rod ígu z-Rivera, S. T. Evans, and J. A. Dumesic, Angew. Chem. Int. Ed. 44, 778-792 (2005).

Figure 1: A schematic diagram representation of a single-transistor non-volatile memory cell, indicating the aimed substitution of the poly-Si floating gate (FG) with an array of polyoxometalate clusters (POM layer).

Figure 2: Graphical representation comparing the HOMO–LUMO gap in eV for [W18O54(SO4)2]4- (left) and (right) Wells-Dawson anion [W18O54 (SO3)2]4-.

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O-D4-01-02

Catalytic Asymmetric Total Synthesis of (+)-Caprazol

Takumi Watanabe, Purushothaman Gopinath, Lu Wang, Hikaru Abe, Gandamala Ravi, Takashi Masuda, and Masakatsu Shibasaki

Institute of Microbial Chemistry (BIKAKEN), 141-0021, Tokyo, [email protected]

Catalytic asymmetric total synthesis of caprazol, a lipo-nucleoside antibiotic, has been accomplished employing two of the stereoselective C-C bond forming reactions as key transformations. The stereochemistries of the b-hydroxy-a-aminoester moiety at the juncture of uridine part and diazepanone part, and of the b-hydroxy-a-amino acid moiety embedded in the diazepanone system, were constructed using diastereoselective isocyanoacetate aldol reaction (dr = 88:12) and enantioselective anti-nitroaldol reaction catalyzed by Nd/Na-chiral amide ligand (dr = 12:1, 95% ee), respectively.1

Figure 1: Synthetic strategy of (+)-caprazol.

References1. P. Gopinath, L. Wang, H. Abe, G. Ravi, T. Masuda, T. Watanabe, and M. Shibasaki, submitted.

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O-D4-01-03

PREPARATION, STRUCTURE AND APPLICATIONS OF CHIRAL ORGANOMAGNESIATES: DUAL REAGENTS FOR HALOGEN-MAGNESIUM

EXCHANGE OF 2-AZINYLPYRIDINES AND ACCESS TO CHIRAL AZINYLCARBINOLS

Philippe C Gros1, Delphine Catel1, Olivier Payen1, Floris Chevallier2, Florence Mongin2, Charles O’Hara3, Javier Francos3

1HECRIN, SRSMC, Université de Lorraine, CNRS, Nancy (France) 2CPM, UMR 6510, Université de Rennes, CNRS, Rennes (France)

3Department of Pure and Applied Chemistry, University of Strathclyde, Glasgow (Scotland)

Ate complexes of general formula RnMLin-2 are promising species since several reactive ligands can be bound to the central metal (M). These ligands can be easily transferred to perform selective deprotonations or halogen-metal exchanges leading to a straightforward metallation of the substrates.1 Moreover these reagents offer a greater stability than their organolithium counterparts allowing reactions to be performed under non-cryogenic conditions. The ability to host several ligands opens the way to asymmetric processes especially enantioselective additions by using chiral ligands. Our aim is to design reagents able to promote bromine-metal exchange while transferring chirality to the metallated substrate. The idea is to exploit the stability of the metal-ligand bond to create a well-defined and robust chiral environment. The concept has been applied to the synthesis of chiral heteroarylcarbinols, a good enantioselectivity was obtained using (R,R)-TADDOL or BIPHEN H2 as ligands.2,3 Besides synthetic results, structural studies (X-Ray and NMR) of organometallic intermediates will be presented.

Figure 1: Chiral organomagnesiate, structure and asymmetric synthesis

References1. N. T. T. Chau, M. Meyer, S. Komagawa, F. Chevallier, Y. Fort, M. Uchiyama, F. Mongin, P.C. Gros, Chem. Eur. J. 2010, 16, 12425.

3. D. Catel, F. Chevallier, F. Mongin, P. C. Gros, Eur. J. Org. Chem. 2012, 53. (Eurbest in EurJOC)

4. Tilly,D., Chevallier, F., Mongin, F., Gros, P.C. Bimetallic Combinations for Dehalogenative Metalation Involving Organic Compounds. Chem. Rev., 2014, 114(2), 1207–1257.

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O-D4-01-04

ENANTIOSELECTIVE ADDITION OF WATER

U. Hanefeld1

1Gebouw voor Scheikunde, Afdeeling Biotechnologie, Technische Universiteit Delft, Julianalaan 136, 2628BL Delft, The Netherlands


Water is a very bad nucleophile and notoriously unreactive. Its direct addition to double bonds is therefore a major challenge in chemistry. The Michael addition of water is catalyzed by amino acids and some amines, however it is very slow and yields are often low in this reaction [1]. Very few examples of enantioselective Michael additions of water have been described and most of them are enzyme catalyzed [2]. These enzymes, hydratases, however suffer in most cases from a very narrow substrate scope. Indeed some only accept one single substrate.

Rhodococcus species have the ability to catalyze the Michael addition of water [3,4]. This activity has now been explored and remarkable activities and enantioselectivities have been found. It seems that a wide range of related Rhodococcus species can catalyze these reactions. These straightforward to use catalysts can easily be recycled and used many times. Moreover they catalyze the reaction in the reagent water, leading to a very environmentally benign reaction with an excellent atom economy.

R1 OR2

+ H2O

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- H2O

O

O

O

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ee >

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many Rhodoccus species

Figure 1: The addition of water is notoriously difficult. The enantioselective Michael addition of water is catalyzed by Rhodococcus species, opening up entirely new ways to 3-hydroxy carbonyl compounds.

The reaction occurs enantioselectively as anti-addition. In the presentation the substrate range and selectivity of the catalysts will be discussed.

References1. V. Resch, C. Seidler, B. S. Chen, I. Degeling, U. Hanefeld, Eur. J. Org. Chem., 7697 (2013).2. Jianfeng Jin and Ulf Hanefeld, Chem. Commun., 47, 2502 (2011).3. H. L. Holland, J.-X. Gu, Biotechnol. Lett., 20, 1125 (1998).4. B.-S. Chen, L. G. Otten, V. Resch, G. Muyzer, U. Hanefeld, Stand. Genom. Sci. 9, 175 (2013).

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O-D4-01-05

BREAKING THE MIRROR: SYNTHESIS AND PURIFICATION OF ASYMMETRIC POM HYBRIDS

A. Macdonell1, L. Cronin.*1

1WestCHEM, School of Chemistry, The University of Glasgow, G12 8QQ, UK Presenting author: [email protected]

Polyoxometalate (POM) clusters - discrete metal-oxide molecules - are highly catalytically [1] and electronically [2] active and possess a wealth of unique properties, many of which synergise very well with the functionalities of organic molecules. The field of hybrid POMs connects organic moieties directly to inorganic cores via covalent or coordinate bonds, producing a new range of structures often with complex properties, but the POM cores often requires reworking of con-ventional organic techniques.

For the Mn-Anderson hybrid cluster, which has two TRIS-based organic moieties – one on each side of the planar POM core – one of the biggest challenges is the purification of so-called “asymmetric” hybrid compounds where the two organic moieties are different. The synthesis of these compounds is simple, but always includes the production of two symmetric by-products from which it is very challenging to separate the desired asymmetric compound. We have developed an LC based method which successfully separates POM clusters based on the affinities of their organic components, proved its efficacy with a number of asymmetric Mn-Anderson hybrids and also provided a “Universal” asymmetric compound which can be purified itself then used as a starting material for forming pure asymmetric compounds directly. These asymmetric compounds have a wealth of potential applications beyond those which the symmet-ric compounds can provide.

References

1. A. Proust, R. Thouvenot, and P. Gouzerh, Chem. Comm., 1837-1852 (2008).2. M. Sadakane, and E. Steckhan, Chem. Rev. 98, 219-238 (1998).3. C. Yvon, A. Macdonell, S. Buchwald, A. J. Surman, N. Follet, J. Alex, D.-L. Long, and L. Cronin, Chem. Sci. 4, 3810-3817 (2013).

BREAKING THE MIRROR:

SYNTHESIS AND PURIFICATION OF ASYMMETRIC POM HYBRIDS

A. Macdonell1, L. Cronin.*1 1WestCHEM, School of Chemistry, The University of Glasgow, G12 8QQ, UK


Polyoxometalate (POM) clusters - discrete metal-oxide molecules - are highly catalytically [1] and electronically [2] active and possess a wealth of unique properties, many of which synergise very well with the functionalities of organic molecules. The field of hybrid POMs connects organic moieties directly to inorganic cores via covalent or coordinate bonds, producing a new range of structures often with complex properties, but the POM cores often requires reworking of conventional organic techniques. For the Mn-Anderson hybrid cluster, which has two TRIS-based organic moieties – one on each side of the planar POM core – one of the biggest challenges is the purification of so-called "asymmetric" hybrid compounds where the two organic moieties are different. The synthesis of these compounds is simple, but always includes the production of two symmetric by-products from which it is very challenging to separate the desired asymmetric compound. We have developed an LC based method which successfully separates POM clusters based on the affinities of their organic components, proved its efficacy with a number of asymmetric Mn-Anderson hybrids and also provided a "Universal" asymmetric compound which can be purified itself then used as a starting material for forming pure asymmetric compounds directly. These asymmetric compounds have a wealth of potential applications beyond those which the symmetric compounds can provide.

References 1. A. Proust, R. Thouvenot, and P. Gouzerh, Chem. Comm., 1837-1852 (2008). 2. M. Sadakane, and E. Steckhan, Chem. Rev. 98, 219-238 (1998). 3. C. Yvon, A. Macdonell, S. Buchwald, A. J. Surman, N. Follet, J. Alex, D.-L. Long, and L. Cronin, Chem. Sci. 4, 3810-3817 (2013).

Figure 1: Reaction scheme showing the first synthesis of an asymmetric Mn-Anderson and the

statistical distribution of products.

Figure 2: A simplified scheme showing the combination of symmetric and asymmetric products being separated on an LC column and eluted with different retention times.

BREAKING THE MIRROR:

SYNTHESIS AND PURIFICATION OF ASYMMETRIC POM HYBRIDS

A. Macdonell1, L. Cronin.*1 1WestCHEM, School of Chemistry, The University of Glasgow, G12 8QQ, UK


Polyoxometalate (POM) clusters - discrete metal-oxide molecules - are highly catalytically [1] and electronically [2] active and possess a wealth of unique properties, many of which synergise very well with the functionalities of organic molecules. The field of hybrid POMs connects organic moieties directly to inorganic cores via covalent or coordinate bonds, producing a new range of structures often with complex properties, but the POM cores often requires reworking of conventional organic techniques. For the Mn-Anderson hybrid cluster, which has two TRIS-based organic moieties – one on each side of the planar POM core – one of the biggest challenges is the purification of so-called "asymmetric" hybrid compounds where the two organic moieties are different. The synthesis of these compounds is simple, but always includes the production of two symmetric by-products from which it is very challenging to separate the desired asymmetric compound. We have developed an LC based method which successfully separates POM clusters based on the affinities of their organic components, proved its efficacy with a number of asymmetric Mn-Anderson hybrids and also provided a "Universal" asymmetric compound which can be purified itself then used as a starting material for forming pure asymmetric compounds directly. These asymmetric compounds have a wealth of potential applications beyond those which the symmetric compounds can provide.

References 1. A. Proust, R. Thouvenot, and P. Gouzerh, Chem. Comm., 1837-1852 (2008). 2. M. Sadakane, and E. Steckhan, Chem. Rev. 98, 219-238 (1998). 3. C. Yvon, A. Macdonell, S. Buchwald, A. J. Surman, N. Follet, J. Alex, D.-L. Long, and L. Cronin, Chem. Sci. 4, 3810-3817 (2013).

Figure 1: Reaction scheme showing the first synthesis of an asymmetric Mn-Anderson and the

statistical distribution of products.

Figure 2: A simplified scheme showing the combination of symmetric and asymmetric products being separated on an LC column and eluted with different retention times.

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O-D4-01-06

Nucleophilic Boron: New Opportunities for Carbon-Boron Bond

M. Tortosa, A. Parra, L. Amenós, A. López, M. Guisán, J. Alemán, R. Alfaro

Departamento de Química Orgánica, Universidad Autónoma de Madrid, Cantoblanco, 28049 Madrid, Spain


Boronic esters are versatile synthetic intermediates for the preparation of a wide range of organic molecules. The development of new methods to create C-B bonds in an efficient, inexpensive, and environmentally friendly way is therefore an important challenge in organic chemistry. Traditionally, the methods to form C-B bonds have mostly been based on the electrophilic nature of boron. While this classical approach works well for reactions with nucleophilic partners, it naturally limits the types of boron compounds that can be prepared. Recently, copper-catalyzed borylations have emerged as a new source of nucleophilic boron. The lower price and toxicity of copper versus other transition metals and the unique reactivity of the boryl-copper intermediates make these processes particularly attractive. Inspired by unsolved problems found in the total synthesis of complex molecules, we have used boryl-copper species to synthesize 1,4-diols,1 trisubstituted alkenes,2 and cyclopropyl derivatives.3 These studies will be presented in this talk.

Me

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S

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OH

References

1. M. Tortosa, Angew. Chem. Int. Ed. 50, 3950 (2011).2. R. Alfaro, A. Parra, J. Alemán, J. L. García-Ruano, M. Tortosa J. Am. Chem. Soc. 134, 15165 (2012).3. A. Parra, L. Amenós, M. Guisán, A. López, J. L. García-Ruano, M. Tortosa Manuscript under

preparation

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O-D4-01-07

Synthesis of isocyanide derived natural products with antibiotic activity

Richard A. R. Blackburn1, Nicholas R. Waterfield2, Steven D. Bull1

1Department of Chemistry, University of Bath, UK,2 The Division of Microbiology and Infection, University of Warwick, UK


The insect pathogens Xenorhabdus and Photorhabdus are responsible for the production of a series of vinyl isocyanide metabolites (figure 1), which are deployed by the bacteria to combat the insect host’s immune system and defend against competing organisms (bacteria). Our development of a highly E selective Horner-Wadsworth-Emmons reagent and its subsequent reaction has been essential in enabling us to achieve the total syntheses of this novel class of isocyanide natural products.

Figure 1 –Vinyl isocyanide derived natural products, which we have now synthesised and biologically evaluated

The promising antibacterial activity that we found for these natural products (figure 2) has led us to employ our versatile synthetic methodology for the construction of a small library of heterocyclic and substituted phenol vinyl isocyanides, which have also greatly inhibited the growth of the various strains of clinically relevant S. aureus (including methicillin resistant),

Fig 2. –Initial Antibiotic Activity screens (phenol vinyl isocyanide shown)Since a key component of an insect’s immune response is the tyrosinase enzyme Phenol-Oxidase’s ability to coat invading pathogens with an impermeable coat of melanin, we have complemented our on-going biological studies with targeting the ability of these natural products, and indeed their analogues, to inhibit tyrosinases, and their potential to function as inhibitors to suppress melanoma.

Key References:[1] H. B. Bode, Curr. Opin. Chem. Biol., 2009, 13, 224-30.[2] N. R. Waterfield, T. Ciche, and D. Clarke, Ann. Rev. Microb., 2009, 63, 557[3] J. M. Crawford and J. Clardy, Chem. Commun., 2011, 47, 7559-7566.[4] S.F. Brady, J. Am. Soc., 2007, 129, 12102-12103

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O-D4-02-02

Transition-Metal-Catalyzed Annulation Reactions of Cyclopropenones

Takanori Matsuda and Yusuke Sakurai

Department of Applied Chemistry, Tokyo University of Science, 1-3 Kagurazaka, Shinjuku-ku, Tokyo 162-8601, Japan


Cyclopropenones are highly strained molecules that exhibit unique reactivity. We have succeeded in developing a series of transition-metal-catalyzed annulation reactions of cyclopropenones that involve cleavage of the carbon–carbon bonds.A palladium-catalyzed addition reaction of terminal alkynes to cyclopropenones resulted in ring opening to give alkenyl alkynyl ketones (Eq. 1) [1]. In the case of the reaction using propargyl esters, the resulting alkenyl alkynyl ketones undergo a Nazarov-type cyclization under the reaction conditions to afford 4-alkylidene-cyclopent-2-enones.

(1)

Reaction between 1,6-enynes and cyclopropenones in the presence of a gold(I) catalyst furnished spirocyclic structures (Eq. 2) [2]. A molecule of water was incorporated during the spiroannulation to give spirocyclic cyclopent-2-enones containing a hydroxyl group. The spiroannulation proceeded with complete diastereoselectivity.

(2)

On the other hand, the [2+2+2] cycloaddition of 1,6-enynes with cyclopropenones occurred in the presence of a cationic rhodium(I) catalyst (Eq. 3). Insertion of the tetrasubstituted alkene moiety was favored over that of the carbonyl group in the cycloaddition. The resulting cycloadduct possessing an alkenylcyclopropanone moiety underwent 1,3-acyl rearrangement under the reaction conditions to give tricyclic cyclopent-3-enones.

(3)

The scope and proposed mechanism of these reactions will be presented.

References1. T. Matsuda and Y. Sakurai, Eur. J. Org. Chem., 4219 (2013).2. T. Matsuda and Y. Sakurai, J. Org. Chem. 79, 2739 (2014).

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O-D4-02-03

Gaining insight in the control of the regioselectivity of palladium-catalyzed allylic amination of linear allylic carbonates. Application in the synthesis of natural

products

S. Soriano, J. Llaveria, M. Azzouz, M.I. Matheu, Y. Díaz, S. Castillón1Departament de Química Anlítica i Química Orgànica, Facultat Rovira i Virgili, 43007 Tarrgona,

SpainPresenting author: [email protected]

Palladium-catalyzed allylic substitution is one of the most powerful methods for the construction of carbon-heteroatom and carbon-carbon bonds.1 Despite the importance of this transformation and the enormous amount of work in this field, the control of regioselectivity is still an unresolved problem, limiting the chances for the development of asymmetric versions. Despite the importance of this transformation and the enormous amount of work in this field, the control of regioselectivity is still an unresolved problem, limiting the chances for the development of asymmetric versions. Indeed, with the exception of a few examples, the easily accessible linear monosubstituted allylic electrophiles are not suitable substrates for asymmetric palladium-catalyzed substitution, because they typically yield achiral, linear substituted products.2 In this communication, we describe our investigations on Pd-catalyzed allylic amination reactions of linear allylic carbonates with different N-nucleophiles, showing that regioselectivity can be tuned by an interplay of steric and hydrogen bonding interactions due to the presence or absence of protecting groups at the OR group. This method can be used to give access to enantioenriched branched allylic amines using the DPPBA catalysts developed by Trost. This protocol was used in the synthesis of natural products such as phytosphingosine, jaspine, nectrisine and fogamine.

HOOCO2Me [Pd]

/ L

N-nucleophileRO

∗

NRR'

HN

HO

HOOH

D-fagomine

HO

NH2

OH

OH

13

N

HO OH

HO

nectrisine

regio- and enanatioselectivitycontrol

phytosphingosine

O

HO OH

C14H29

jaspine

1 For selected publications see a) Trost, B. M. J. Org. Chem. 2004, 69, 5813-5837. b) Mori, M. Chem. Pharm. Bull. 2005, 53, 457-470. c) Trost, B. M.; Crawley. Chem. Rev. 2003, 103, 2921- 2943. d) Belda, O.; Moberg, C. Acc. Chem. Res. 2004, 37, 159-167. e) Sawamura, M.; Ito, Y. Chem. Rev. 1992, 92, 857-871. f) Trost, B. M. Pure. Appl. Chem. 1996, 68, 779-784.2 Hartwig, J. F.; Stanley, L. M. Acc. Chem. Res. 2010, 43, 1461-1475.

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O-D4-02-04

Palladium-Catalyzed [2+1] Cycloaddtion and Ring Expansion: a New Methodology for the Synthesis of 7-Membered Carbocycles

H. Clavier,1 A. Lepronier,1 T. Achard,1 L. Giordano,1 A. Tenaglia,1 G. Buono.1

1Institut des Sciences Moléculaires de Marseille (iSm2) UMR CNRS 7313 –Aix-Marseille Université – École Centrale de Marseille 13397 Marseille Cedex 20 – France


Although less commonly encountered in nature than six-membered rings or smaller, seven-membered carbocycles has drawn attention due to their biological relevance as stated by their presence as core skeletons in many natural products.[1] However, the development of new and efficient methodologies for the formation of such carbocycles is still challenging due to entropic and enthalpic factors. So far, the most popular strategies for the construction of 7-membered carbocycles include mainly cycloaddition routes ([4+3] or [5+2]).[2]

In the course of a research program dedicated to study the catalytic properties of palladium- and platinum-based complexes bearing secondary phosphine oxides (SPO), we discovered an original [2+1]-cycloaddition between norbornene derivatives and alkynes.[3,4] Its scope investigation showed that in the case of tertiary propargyl acetate a particular [2+1] cycloadduct, an allenylidenecyclopropane, was isolated.[5]

In order to develop a new methodology for the construction of the 7-membered, we further investigated the reactivity of allenylidenecyclopropanes using oxanorbornene-based substrates. We were able to obtain bicyclo[3.2.1]octadiene derivatives by palladium-catalyzed ring expansion using carboxylic acids. The parameters governing these transformations, its scope as well as mechanistic considerations will be presented (Scheme 1). Finally, we will be described our efforts to open the oxa-bridge affording carbocycles.

Scheme 1: Palladium-catalyzed [2+1] cycloaddition and ring expansion

References1. M. B. Fraga, Nat. Prod. Rep. 22, 465 (2005).2. H. Pellissier, Adv. Synth. Catal. 353, 189 (2011)3. J. Bigeault, L. Giordano and G. Buono, Angew. Chem. Int. Ed. 44, 4753 (2005).4. J. Bigeault, L. Giordano, I. de Riggi, Y. Gimbert and G. Buono, Org. Lett. 9, 3567 (2007).5. J. Bigeault, I. de Riggi, Y. Gimbert, L. Giordano and G. Buono, Synlett, 1071 (2008)

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O-D4-02-05

UNPRECEDENTED ALKOXY- AND ARYL-SUBSTITUED ENAMIDES BY METAL-ASSISTED α-ADDITION TO YNAMIDES

L. Graux1, H. Clavier1, G. Buono.1

1Aix Marseille University – iSm2 CNRS ECM UMR 7313Campus Scientifique St Jérôme Case 462, Av Escadrille Normandie-Niemen

13397 Marseille Cedex [email protected]

Alkynes and hetero-substituted alkynes are useful synthons in organic synthesis as attested by the impressive number of reports dealing with their reactivity. Recent advances in the preparation of elec-tron-deficient aza-substituted alkynes, ynamides, allowed the development of versatile transformations using theses substrates.[1] They represent an excellent way to introduce nitrogen functions into organic compounds. Ynamides have a limit form keteniminium ion that reveals their reactivity: reaction with electrophiles on the β position to the nitrogen atom and nucleophilic addition on α position. Several metal-promoted α-addition have been described in the literature with nucleophiles such as halides, amines, alcohols or carboxylic acids.[2]

During the course of studies dealing with the use of ynamides as partner in palladium-catalyzed [2+1] cycloaddition [3], our group discovered that phosphapalladacycle were able to catalyze the α-addition of 1,3-diketones to ynamides affording unprecedented alkoxy-substitued enamides (Figure 1). We then further explored this transformation by the screening of various catalytic systems. Cationic gold com-plex showed an activity similar to the one of phosphapalladacycle. On the other hand, the use of cat-ionic ruthenium complexes allowed to broaden the α-addition other nucleophiles such as activated aryles. Other parameters governing the reactivity of those transformations as well as their scope will be presented.

R1 NR2

EWG

αβ

Ynamide

[Pd] or [Au]

NR2

EWG

R1H

O NR2

EWG

R1HO

OO

[Ru]

HR

R

Figure 1: Metal assisted α-addition to ynamides

References1. G. Evano , K. Jouvin and A. Coste, Synthesis 45, 17 (2013).2. (a) K. A. DeKorver, H. Li, A. G. Lohse, R. Hayashi, Z. Lu, Y. Zhang and R. P. Hsung, Chem. Rev. 110, 5064 (2010). (b) G. Evano, A. Coste and K. Jouvin, Angew. Chem Int. Ed. 49, 2840 (2010) (c) D. L. Smith, W. R. F. Goundry and H. L. Lam, Chem. Commun. 48, 1505 (2012).3. H. Clavier, A. Lepronier, N. Bengobesse-Mintsa, D. Gatineau, H. Pellisier, L. Giordano, A. Tenaglia and G. Buono, Adv. Synth. Catal. 355, 403 (2013).

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O-D4-03-02

FROM CARBANIONS TO ORGANOMETALLIC COMPOUNDS: QUANTIFICATION OF METAL-ION-EFFECTS ON NUCLEOPHILIC

REACTIVITIES

Francisco Corral Bautista, Roland Appel, Lydia Klier, Paul Knochel, Herbert Mayr

Department Chemie, Ludwig-Maximilians-Universität München, München, GermanyPresenting author: [email protected]

Organometallic compounds belong to the most important reagents in organic synthesis, which allow chemo- and stereoselective transformations. Depending on the nature of the metal, the carbon-metal bond is more or less covalent and influences drastically the properties of the compound such as its reactivity, selectivity and tolerance towards functional groups.[1]

Kinetic investigations of the reactions of different metal organic compounds (alkali metals, zinc, tin, silicon) towards benzhydrylium ions and Michael acceptors (reference electrophiles) allowed us to quantify their nucleophilic reactivities according to the linear free energy relationship given in equation (1), in which electrophiles are characterized by one parameter, E, and nucleophiles are characterized by the solvent-dependent parameters sN (sensitivity) and N (nucleophilicity).[2,3]

)()C20(lg N2 ENsk +=° (1)

In the past, we quantified the nucleophilic reactivities of numerous stabilized carbanions as well as of organosilanes and stannanes using equation (1).[3] We now varied the metal while keeping the “carbanionic” fragment (cyclopentadienyl-, indenyl-, fluorenyl-, etc.) constant and thus quantified the influence of the counter-ion and/or the coordinated metal on the reactivity (Figure 1). We furthermore show how the nucleophilic reactivity of carbanions and zinc-reagents is affected by additives (alkali salts).

Met

KNaLiZnClSnMe3SiMe

3

+ Ar2CH+

CHAr2

k2

k2(rel)1 104 108 1012 1016

Figure 1: Relative reactivities of different metal-organic derivatives towards benzhydrylium ions.

References:1) T. Klatt, J. T. Markiewicz, C. Sämann, P. Knochel, J. Org. Chem. 2014, DOI: 10.1021/jo500297r;

B. Haag, M. Mosrin, H. Ila, V. Malakov, P. Knochel, Angw. Chem. Int. Ed. 2011, 50, 9794-9824; P. Knochel, Handbook of Functionalized Organometallics, Wiley-VCH, Weinheim 2005.

2) H. Mayr, T. Bug, M. F. Gotta, N. Hering, B. Irrgang, B. Janker, B. Kempf, R. Loos, A. R. Ofial, G. Remennikov, H. Schimmel, J. Am. Chem. Soc. 2001, 123, 9500–9512.

3) For a comprehensive listing of nucleophilicity parameters N, sN and electrophilicity parameters E, see http://www.cup.uni-muenchen.de/oc/mayr/DBintro.html.

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O-D4-03-03

Double Cyclization Isomerization Polymerization of Trienes by Pd Complex

Kenya Motokuni1, Daisuke Takeuchi2, Kohtaro Osakada2

1Faculty of Chemistry and Earth Sciences, Jena University, Germany2Chemical Resources Laboratory, Tokyo Institute of Technology, Japan


Cyclopolymerization of dienes is one of the methods to synthesize cyclic olefin polymer (COP). It has been difficult to control the stereochemistry of the cyclic structure by using conventional catalysts. Polymerization of trienes that have three olefins in one molecule is expected to afford two cycloalkanegroups in one repeating unit during the polymerization as a result of double-cyclization. However, there has been no report on successful controlled double-cyclopolymerization of trienes. Recently, we have found that diimine Pd complex also promote doublecyclopolymerization of functionalized trienes to afford polymers with bis-cyclopentane ring, racemo stereochemistry1. This Pd complex also promote the isomerization cyclopolymerization of 7-alkyl-1,6-dienes to produce the polymers with non-conjugated dienes is one of the methods to synthesize polymers with cycloalkane groups on the polymer chain2. Herein, we report double cyclization isomerization polymerization (DCIP) of functionalized triene by Pd conplexes.

Diimine Pd complex in combination with NaBARF (BARF = [B{C6H3(CF3)2-3,5}4]-) proceed

polymerization of monoterminal 1,6,11-dodecatrienes with cyclic acetal group on 4 position and cyclic ester group on 9 position by quantitative reaction (Eq. 1). The obtained polymer contains two trans-fused five-membered rings in every repeating unit, which are controlled in racemo-configuration selectively. The density of the bis-cyclopentane rings can be regulated by the length of alkyl chain of the monomer. The cyclopentanes with cyclic acetal and cyclic ester groups can be placed alternatingly along the polymer chain.

1,6,13-heptadecatriene which have intervals between two functional groups also undergoes double-cyclopolymerization accompanying isomerization (Eq. 2). The formed polymer again contains two functionalized cyclopentane groups in alternating manner along the polymer chain and the intervals between those groups can be controlled by the length of oligomethylene spacer and alkyl group of the monomer.

References1. Kenya Motokuni, Takeshi Okada, Daisuke Takeuchi, Kohtaro Osakada, Macromolecules 44, 751 (2011).2. Takeshi Okada, Daisuke Takeuchi, Kohtaro Osakada, Angew.Chem 46, 6141 (2007).

Double Cyclization Isomerization Polymerization of Trienes by Pd Complex

Kenya Motokuni1, Daisuke Takeuchi2, Kohtaro Osakada2 1Faculty of Chemistry and Earth Sciences, Jena University, Germany

2Chemical Resources Laboratory, Tokyo Institute of Technology, Japan Presenting author: [email protected]

Cyclopolymerization of dienes is one of the methods to synthesize cyclic olefin polymer (COP). It has been difficult to control the stereochemistry of the cyclic structure by using conventional catalysts. Polymerization of trienes that have three olefins in one molecule is expected to afford two cycloalkanegroups in one repeating unit during the polymerization as a result of double-cyclization. However, there has been no report on successful controlled double-cyclopolymerization of trienes. Recently, we have found that diimine Pd complex also promote doublecyclopolymerization of functionalized trienes to afford polymers with bis-cyclopentane ring, racemo stereochemistry1. This Pd complex also promote the isomerization cyclopolymerization of 7-alkyl-1,6-dienes to produce the polymers with non-conjugated dienes is one of the methods to synthesize polymers with cycloalkane groups on the polymer chain2. Herein, we report double cyclization isomerization polymerization (DCIP) of functionalized triene by Pd conplexes.

Diimine Pd complex in combination with NaBARF (BARF = [B{C6H3(CF3)2-3,5}4]-) proceed polymerization of monoterminal 1,6,11-dodecatrienes with cyclic acetal group on 4 position and cyclic ester group on 9 position by quantitative reaction (Eq. 1). The obtained polymer contains two trans-fused five-membered rings in every repeating unit, which are controlled in racemo-configuration selectively. The density of the bis-cyclopentane rings can be regulated by the length of alkyl chain of the monomer. The cyclopentanes with cyclic acetal and cyclic ester groups can be placed alternatingly along the polymer chain.

1,6,13-heptadecatriene which have intervals between two functional groups also undergoes double-cyclopolymerization accompanying isomerization (Eq. 2). The formed polymer again contains two functionalized cyclopentane groups in alternating manner along the polymer chain and the intervals between those groups can be controlled by the length of oligomethylene spacer and alkyl group of the monomer.

References 1. Kenya Motokuni, Takeshi Okada, Daisuke Takeuchi, Kohtaro Osakada, Macromolecules

44, 751 (2011). 2. Takeshi Okada, Daisuke Takeuchi, Kohtaro Osakada, Angew.Chem 46, 6141 (2007).

NaBARFCH2Cl2, r.t.

n

NPd

N

Me Cl

O O O O

OO

(CH2)nH

n = 1, 2, 3, 10

m(1) n

Controlled Interval

(2)

O O O O

OO

NaBARFCH2Cl2, r.t.

NPd

N

Me Cl

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O-D4-03-04

AIR-STABLE NICKEL(0) PHOSPHITES AS CATALYSTS FOR C-N AMINATIONS

Sven S. Kampmann1, A. N. Sobolev1, G. A. Koutsantonis1, S. G. Stewart1

1The School of Chemistry and Biochemistry, The University of Western Australia, Crawley, Perth, WA 6009, Australia


Nickel catalysis is increasingly being used in cross coupling chemistry as a reactive and cost effective alternative to palladium catalysis. In this work we describe the design and preparation of inexpensive air stable nickel(0) phosphite based catalysts for use in C-N coupling reactions.

Commonly, bis(cyclooctadiene)nickel(0) (Ni(COD)2) is used as a nickel(0) source.[1,2]Although generally being very active, this pre-catalyst has numerous drawbacks such as being highly air-sensitive, difficult to transport, costly, and difficult to prepare. We therefore sought an air-stable and cheaper alternative to Ni(COD)2. Previously, nickel phosphite complexes have been used to a limited extent in Heck cross coupling reactions.[3] Initially, we explored the use of Ni[P(OPh)3]4, with moderate success, eventually leading to the serendipitous discovery of the novel nickel complex 1.

1

X

R

+

RR'NH

Ni[P(OPh)3]4 (5

mol%)ligand, NaOtBu

or

(dppf)Ni[P(OPh)3]4 (1)

(5

mol%)dppf

(5

mol%) or BINAP

(5

mol%) NaOtBu

toluene, 100 °C, 18

h

RN

R'

R

44 examples

yields up to

99

%

Figure 1: Nickel catalyzed C-N cross coupling reactions utilizing novel phosphite based catalyst 1.

This new nickel(0) complex not only gave yields comparable with those achieved using Ni(COD)2, but also proved to be air-stable. Complex 1 serves as an excellent catalyst for C-N amination reactions of various aryl halides with anilines or amines. Interestingly, the addition of a second phosphine (dppf or BINAP) assists in the coupling process. In this primary investigation, we have also identified early steps of the reaction mechanism, indicating dissociation of the chelating phosphine rather than the phosphite.[4]

References[1] J. P. Wolfe, S. L. Buchwald, J. Am. Chem. Soc. 1997, 119, 6054-6058.[2] L. Ackermann, R. Sandmann, W. Song, Org. Lett. 2011, 13, 1784-1786.[3] S. Iyer, C. Ramesh, A. Ramani, Tetrahedron Lett. 1997, 38, 8533-8536.[4] S. S. Kampmann, A. N. Sobolev, G. A. Koutsantonis, S. G. Stewart, Adv. Synth. Catal. 2014,

accepted, DOI: 10.1002/adsc.201400201.

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O-D4-03-05

Palladium-Catalyzed Carbonylations of Aryl Bromides using Paraformaldehyde: Synthesis of Aromatic Aldehydes and Esters

Kishore Natte, Helfried Neumann, and Matthias Beller

Leibniz-Institut für Katalyse an der Universität RostockAlbert-Einstein-Straße 29a, 18059 Rostock (Germany)

Fax: (+49) 381-1281-5000Presenting author: [email protected]

Aromatic aldehydes carrying additional substituents are an important class of compounds that are widely used in organic synthesis as versatile intermediates. In addition, they are produced on larger scale in the pharmaceutical, agrochemical and fine chemical industries as valuable building blocks. Despite their importance, the efficient and selective synthesis of functionalized benzaldehydes is still challenging. Esters represent another important class of compounds in organic synthesis and this structural motif is found in numerous pharmaceuticals, agrochemicals, fragrances, and polymers. In recent years palladium-catalyzed coupling reactions have become a “true power” tool for organic synthesis. All kinds of coupling reactions are nowadays routinely applied for efficient functionalizations of arenes and heteroarenes. In this respect also carbonylative coupling reactions have become of importance. Unfortunately, the use of toxic CO and the need for high pressure infrastructure refrain organic chemists to apply these methodologies more often. Hence, there exist significant interest in alternative procedures. In this context, Manabe and co-workers reported an interesting palladium-catalyzed reductive carbonylation of aryl halides using N-formylsaccharin and phenyl formate as CO source [1]. Liu and co-workers reported the Pd/C-catalyzed direct formylation of aromatic iodides to aryl aldehydes using CO2 and silanes [2].Herein, we report the first successful application of readily available paraformaldehyde in a CO gas-free synthetic protocol for the Pd-catalyzed carbonylations of aryl bromides. This novel approach offers a convenient synthesis of a variety of (hetero)aromatic aldehydes and other carboxylic acid derivatives under relatively mild reaction conditions. Notably, paraformaldehyde is a solid, stable, and inexpensive CO surrogate.

O

Ar-Br + (CH2O)n

[Pd]

Ar CH

Ar COR

O

Et3SiH

ROH

Cheap CO

sourceAutoclave/Autoclave

freeCO

gas

free

22 examples

up to

88%

yields

13 examples

up to

81%

yields

Figure 1: Palladium-catalyzed carbonylations of Aryl halidesReferences1. T. Ueda, H. Konishi, K. Manabe, Angew. Chem. Int. Ed. 2013, 52, 8611–86152. 2. B. Yu, Y. Zhao, H. Zhang, J. Xu, L. Hao, X.Gao and Z. Liu, Chem Commun., 2014, 50, 2330-2333

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O-D4-03-06

Integrated Reactions Based on the Umpolung Addition to Conjugated Imines

Makoto Shimizu

Department of Chemistry for Materials, Graduate School of Engineering, Mie University Tsu, Mie 514-8507, Japan

[email protected]

Although nucleophilic addition to the nitrogen atom of simple imines is, in principal, difficult due to the electron negativity of the imino functionality, we have discovered several umpolung N-alkylations of α-iminoesters [1]. The following three topics will be discussed.1. Highly Diastereoselective Tandem N-Alkylation/Mannich Reaction of α-IminoestersWe have found the first highly diastereoselctive tandem N-alkylation-Mannich reaction of α-iminoesteres. The control of diastereoselctivity was readily carried out by choozing either ‘(E)’- or ‘(Z)’-lithium enolate. In most cases, ketene trimethylsilyl acetals could be used with same efficiency, which would also broaden the utility of the present stereocontrol [2].

E/Z = >99/1 R CO2Et

NpAn

Me

OLi

OtBu ( 1.5 eq), THF, -78 , 10min

R

NpAn Et

EtO2C Me

CO2tBu

E/Z = 1 />99OLi

OtBu( 1.5 eq)

THF , -78 , 10min

R

NpAn Et

EtO2C MeMe

syn-selective

CO2tBu

anti-selective

1) BPO (1 eq), Et2AlCl in hex (1 eq) EtAlCl2 in hex (1 eq), DME, rt, 10 min

2) 2)

1) BPO (1 eq), Et2AlCl in hex (1 eq) EtAlCl2 in hex (1 eq), DME, rt, 10 min

up to 95% up to 95%

2. Regioselective Tandem N-Alkylation/C-Acylation of β,γ-Alkynyl α-IminoestersWe have developed a one-pot synthesis of α-quatenary alkynyl amino esters and allenoates using umpolung N-alkylation of β,γ-alkynyl α-iminoesters followed by nucleophilic α- or γ-addition. This method has unique regioselectivity and provides important α-quaternary alkynyl amino acids in good yields. Moreover, it is possible the synthesis of α-quaternary alkynyl amino esters utilizing β,γ-alkynyl α-iminoester with a terminal silyl group via an intermediary iminium salt formed by the oxidation of the amino ester enolate [3].

R1

NpAn

CO2Et

R2MgBr(1.1 equiv) , (5.0 equiv)

THF, -78 oC to rt, 30 minR1

NpAn

CO2Et

R2

R3O

R1

NEt pAn

CO2Et

O R2

EtMgBr(1.1 equiv) ,(2.0 equiv)

THF, -78 oC to rt, 30 min

MgBr2(2.0 equiv)

32 to 100%13 to 86%

R3COClR2COCl,

3. Tandem N-Alkylation/Vinylogous Aldol Reaction of β,γ-Alkenyl α-IminoestersA highly regioselective tandem N-alkylation/vinylogous aldol reaction of β,γ-alkenyl α-iminoesters has been developed. The sulfur group improves the regioselectivity of the vinylogous aldol reaction, providing a new synthetic method of 3-amino-2-pyrones [4].

Ph CO2Et

NpAn

SMe O

O

PhPh

N

pAn

EtO

O

Ph

N

pAn

Et

MeS Ph

+1) EtMgBr

2) PhCHO

32% 64%

m-CPBA 89%

R1 CO2Et

NpAn

R2O

O

R4

R1 R2

N

pAn

R3

2) R4CHO

1) R3MgBr

17 examplesup to 81%

The sulfur group improves the regioselectivity

References1. T. Nishi, I. Mizota, M. Shimizu, Pure Appl. Chem., 84, 2609 (2012); S. Hata, H. Koyama, M.

Shimizu, J. Org. Chem., 76, 9670 (2011); M. Shimizu, I. Hachiya, I. Mizota, Chem. Comm., 874 (2009); M. Shimizu, H. Itou, M. Miura, J. Am. Chem. Soc., 127, 3296 (2005); Y. Niwa, M. Shimizu, J. Am. Chem. Soc., 125, 3720 (2003).

2. M. Shimizu, D. Kurita, I. Mizota, Asian. J. Org. Chem., 3, 208 (2013).3. I. Mizota, Y. Matsuda, S. Kamimura, H. Tanaka, M. Shimizu, Org. Lett., 15, 4206 (2013).4. H. Tanaka, I. Mizota, M. Shimizu, Org. Lett., 16, 2276 (2014).

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O-D4-03-07

Chemical Photocatalysis - Organic Chemistry with Visible Light

Burkhard König

Department of Chemistry and PharmacyUniversity of Regensburg

D-93040 Regensburg, GERMANYPresenting author: [email protected]

The use of visible light for organic synthesis is a very old idea: More than 100 years ago the Italian chemist Giacomo Ciamician discovered and promoted the field. Recently, photoredox chemistry mediated by metal complexes, such as ruthenium-trisbipyridine, or organic dyes, such as eosin, gained enormous interest for applications in organic synthesis.

We discuss the key factors for successful photoredox catalysis (PRC) with visible light in organic synthesis and present some of the recent results1 from our laboratories in this area.

Figure 1: Visible light photoredox catalysis with diazonium salts

References1. Angew. Chem., Int. Ed. 2014, 53, 725; Angew. Chem. Int. Ed. 2013, 52, 4734 (review); Org. Biomol.

Chem. 2013, 11, 6510; J. Am. Chem. Soc. 2012, 134, 2958; Chem. Eur. J. 2013, 19, 1066; Org. Lett. 2012, 14, 5334; J. Org. Chem., 2012, 77, 10347; Angew. Chem. Int. Ed. 2012, 51, 4062; ChemistryOpen 2012, 1, 130; Org. Lett., 2011, 13, 3852.

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O-D4-04-02

CF3CHN2 and C2F5CHN2: novel fluorinating reagents for organic synthesis

P. K. Mykhailiuk,1,2 E. Slobodyanuk,2 A. Artamonov3

11Enamine Ltd., 78 Chervonotkatska Street, 02094 Kyiv, Ukraine2 Chemistry Department, Taras Shevchenko University of Kyiv, Volodymyrska 64, Kyiv 01601,

[email protected], [email protected]

Hardly can one imagine modern organic chemistry without diazo compounds. Their found numerous applications not limiting only to cyclopropanation of alkenes, carbene insertions, [3+2]-cycloadditions, Arndt-Eistert synthesis.By far N2CHCO2Et is probably the most popular diazo compound in chemistry.1 Although some other conceptually attractive low-molecular reagents exist they still remain in shadow of this reagent.In this work, we studied the [2+1]- and [3+2]-cycloadditions of CF3CHN2 and previously unknown C2F5CHN2:

2-7 These reagents proved to be efficient in synthesis of diverse fluorinated compounds not accessible by other methods.

Figure 1: CF3CHN2, C2F5CHN2 and their representative derivatives.

References1. Y. Zhang, J. Wang, Chem.Commun. 5359 (2009).2. A. Artamonov et al., Eur.J.Org.Chem. (2014), in press (DOI: 10.1002/ejoc.201402158).3. E. Slobodyanuk et al., Eur.J.Org.Chem. 12, 2487 (2014).3. P. K. Mykhailiuk, Chem.Eur.J. 20, 4842 (2014).4. A. Artamonov et al., Synthesis 225, (2013).5. A. Artamonov et al., Synthesis 443, (2010).6. P. K. Mykhailiuk et al., Angew. Chem. Int. Ed. 47, 5765 (2008).

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O-D4-04-03

N-Oxides as Environmentally Benign Organocatalysts for Type-1 Baeyer-Villiger Oxidation Reactions of Ketones and α,β-Unsaturated Ketones

Robert S. L. Chapman* Ruth Lawrence, Jonathan M. J. Williams and Steven D. Bull.

Centre for Sustainable Chemical Technologies, Department of Chemistry, University of Bath, Bath, BA2 7AY, UK E. mail: [email protected]

Proton transfer reactions have been shown to be the rate determining steps in many common organic reactions.1-4 This pres-ents an opportunity to catalyse these types of reaction by facilitating proton transfer, a process that is well established in Nature in enzymatic reactions. For example, the “catalytic triad” (Asp-His-Glu) is a highly conserved series of amino acids present in the active site of many hydrolase and transferase enzymes that facilitate tandem proton transfer reactions to lower the transition state of many hydrolysis reactions. In order to employ these type of catalytic proton transfer events in solu-tion, outside of the active site of an enzymes active-site, it is necessary to devise conditions that would enable a Brønsted base to function in the presence of acid; which precludes the use of the majority of common Brønsted bases which are pro-tonated at acidic pH. However, N-oxides have a pKa of around 1.8; which means that they should retain their nucleophilic/basic character in the presence of weak acids (pH > 2.0). We now describe how 4-(dimethylamino)pyridine-N-oxide can be used to catalyse Type I Baeyer-Villiger oxidation reactions, where the rate determining step of these reaction has previously been shown to be initial proton transfer from the meta-chloroperoxybenzoic acid (m-CPBA) to the carbonyl group of the ketone substrate (Figure 1) to afford the tetrahedral intermediate A that then rapidly decomposes via migration of its RM group to afford an observed ester product and an acid by-product.1-4 We believe that the DMAP-N-oxide acts as a Brønsted base to facilitate transfer of a proton from the m-CPBA to the carbonyl of the ketone substrate thus lowering the transition state energy of the initial rate-determining steps of Type I Baeyer-Villiger reactions.

HO

N

O

N

RMR

O OR1

O

R RM

OR1

O

O

HO+

rds

N

O

N

catR

O

ORM

H

O R1

O

R1CO2HR O

RMO

>25 ExamplesRM = Aryl, α,β−Unsaturated

A

Figure 1: DMAP-N-oxide facilitated proton transfer reaction for catalysis of Type 1 Baeyer-Villiger reactions

We have found that 20mol% of DMAP-N-oxide can been used to catalyse the Baeyer-Villiger oxidation reactions of >25 Type I ketones in toluene, affording a rate-enhancement for the formation of their corresponding ester products when com-pared to the corresponding non-catalysed process. This enables significantly improved yields of their corresponding ester products to be obtained using 1.5 equivalents of m-CPBA in toluene at room temperature, with the time (2-24 hrs) required for Baeyer-Villiger reactions to go to completion dependant on the structure of the ketone substrate being oxidised. This catalytic methodology has proven to be particularly useful for catalysing the Baeyer-Villiger reactions of α,β-unsaturated ketones that are normally unreactive under conventional Baeyer Villiger reactions, enabling good yields of their correspond-ing (E)-vinyl esters to be obtained that are not consumed by competing epoxidation reactions that can occur under more forcing conditions.5, 6 The optimal conditions for using DMAP-N-oxide as a catalyst for the formation of (E)-vinyl esters are shown in Figure 2, with the 20mol% pyridine-N-oxide catalyst being generated in situ, via action of excess m-CPBA on the cheap and commercially available parent amine, 4-(dimethylamino)pyridine (DMAP).

mCPBA (1.5 eq.)PhMe, rt, 2 - 24 h

R

O

R' R

O

OR'

N NN N O

20 mol%

20 examples

Figure 1: Optimised reaction conditions for catalysing Baeyer-Villiger reactions of α,β-unsaturated ketones

In conclusion, DMAP-N-oxide has been developed as an efficient metal-free organocatalyst for Type I Baeyer-Villiger reac-tions of ketones that employs a novel proton-transfer mechanism to lower the transition-state energy of the rate determining step of these reactions to afford their corresponding ester products in good yield.

References: 1. L. Reyes, I. Nicolas-Vazquez, N. Mora-Diez and J. R. Alvarez-Idaboy, The Journal of organic chemistry, 2013, 78,

2327-2335. 2. J. R. Alvarez-Idaboy, L. Reyes and N. Mora-Diez, Org Biomol Chem, 2007, 5, 3682-3689. 3. J. R. Alvarez-Idaboy, L. Reyes and J. Cruz, Org. Lett., 2006, 8, 1763-1765. 4. J. R. Alvarez-Idaboy and L. Reyes, J. Org. Chem., 2007, 72, 6580-6583. 5. B. Poladura, A. Martinez-Castaneda, H. Rodriguez-Solla, R. Llavona, C. Con-cellon and V. del Amo, Org. Lett., 2013, 15, 2810-2813. 6. G. R. Krow, Org. React. , 1993, 43, 251.

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O-D4-04-04

Ynamides as controllable diazo-free routes to carbenoids

P. W. Davies1

1School of Chemistry, University of Birmingham, B15 2TT, Birmingham, UKPresenting author: [email protected]

Ynamides are potent substrates that can be readily accessed from simple building blocks.1 Excellent regiocontrol for attack by a nucleophile can be achieved on coordination to a π-acidic metal complexes2 rationalised through the metal-ketene-iminium resonance form contribution. Under appropriate conditions the resulting organometallic species evolve to access carbenoid reactivity. Considering ynamides as potential and immediate precursors to metal carbenes provides the basis for the work presented here where these useful reactive intermediates are accessed in a manner that avoids the normal need to install potentially hazardous and high-energy diazo groups. This talk will highlight how we have employed this approach across a variety of cases.3,4

This presentation will demonstrate how this approach can be applied to range of transformations to rapidly construct functionalised cyclic and acyclic motifs, with high efficiency and functional group tolerance under mild conditions. The role of structure and conditions over reactivity profiles will be discussed alongside issues of selectivity.

PhN

O

Ts65%

NR

R1

N CO2MeO

R2

S

Ph

S

PhN

O

Ts

Ph

S

Representative transformation

NTs

PhPhN

R

R1R2

[Au]

NR

R1

Nu

[Au]

R2

NR

R1

Nu

[Au]

R2E

[Au]N

R

R1

R2

[Au]

No sacrificial diazo group required

Carbene character

High Regiocontrol

Nu

Reactivity Basis

E

[Au] cat.

Figure 1: The use of ynamides to access carbenoid character (LHS) demonstrated in an intermolecular sulfur ylide formation (RHS)

References1. Reviews (a) K. A. DeKorver, H. Li, A. G. Lohse, R. Hayashi, Z. Lu, Y. Zhang, R. P. Hsung, Chem.

Rev., 110, 5064, (2010); (b) G. Evano, A. Coste, K. Jouvin, Angew. Chem., Int. Ed., 49, (2010), 2840.

2. A. Fürstner, P. W. Davies, Angew. Chem. Int. Ed. 46, 3410, (2007).3. Representative examples: (a) H. V. Adcock, T. Langer, P. W. Davies, Chem. Eur. J. DOI:10.1002/

chem.201403040 (2014); (b) M. Dos Santos, P. W. Davies, Chem. Commun. 50, 6001 (2014); (c) P. W. Davies, A. Cremonesi, N. Martin, Chem. Commun. 47, 379 (2011).

4. Website: http://www.birmingham.ac.uk/research/activity/chemistry/Davies/index.aspx

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O-D4-04-05

REDUCTIVE CLEAVAGE OF ARYL NITROSO DIELS-ALDER CYCLOADDUCTS: SYNTHESIS OF CONSTRAINED BICYCLIC GEM-DIAMINES AND NEW

MECHANISTIC INSIGHTS

F. Berti1, V. Di Bussolo1, M. Pineschi1*

1Dipartimento di Farmacia, Università di Pisa, Via Bonanno 33, 56126 Pisa, ItalyPresenting author: [email protected]

Nitroso Diels-Alder cycloadducts are valuable synthetic intermediates as they combine a straightforward preparation to a good molecular complexity [1]. A concise synthesis of α-branched pyrrolamines 4 has recently been reported by us using nitroso cycloadducts of type 2 derived from 1,2-dihydropyridine 1 under copper-catalyzed reductive reaction conditions (path b, Figure 1) [2].

N

ORO

R'

NAr

HNO

OR

R'

ONN

R'

RO

O

Ar

N

NAr

OOR

R'

1 2

3

4

ArNO

CuCl

CuCla

b MeOH

N

R'

O

RO

HN Ar

via

CH2Cl2

CuCl65 °C

Figure 1: Synthesis of constrained gem-diamine 3 and relative key intermediates.

We now report the synthesis of the unprecedented 2,7-diazabicycle[2.2.1]heptane scaffold 3 (path a), showing that this compound is also a stable intermediate in the pyrrole’s pathway. A change of solvent from methanol to dichloromethane arrests the process to the intramolecular addition of the arylamine moiety onto the conjugate N-acyliminium ion 5. Nevertheless, the corresponding pyrrole can be easily obtained increasing the temperature to promote a hetero-Cope rearrangement of compound 3. We also detail the different behaviour and the rich chemistry connected with the use of enantioenriched material when dealing with pyridine nitroso cycloadducts (Ar = Py) [3].

References1. B. S. Bodnar, M. J. Miller, Angew. Chem. Int. Ed. 50, 5630 (2011).2. F. Berti, V. Di Bussolo, M. Pineschi, J. Org. Chem. 78, 7324 (2013). 3. Manuscript under preparation.

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O-D4-05-02

Mono(phosphine)palladium complex-catalyzed efficient Markovnikov addition of transition metal hydride to substituted alkenes and alkynes

S. Komiya1, R. Ito2, N. Komine,2 M. Hirano2

1Gakushuin University, 171-8588, Tokyo, Japan2Tokyo University of Agriculture and Technology, 184-8588, Tokyo, Japan

S. Komiya: [email protected]

Although insertion of alkene and alkyne into transition metal-hydrogen bond is one of the most well-established reactions in organometallic catalysis and reactions, some hydrides such as molybdenum, tungsten and manganese hydrides are very reluctant toward these insertion processes. In the course of our continuing research on heterodinuclear organotransition metal complexes related to still-unsolved cooperative effects between two transition metals in catalysis [1], we recently found efficient hydrometallation of insertion-inactive transition metal hydrides to substituted alkenes and alkynes is accelerated in the presence of catalytic amount of zero-valent palladium complex having tertiary phosphine ligands. In this presentation, reactions and mechanism involving mono(phosphine)palladium-transition metal heterodinuclear complex as active key intermediates to promote the insertion process will be described [2,3], by isolating intermediates and their reaction kinetics.

+H M´R

R M

R

H

´R

M = Mo, W, M, Fe, Si

(cat)O Pd PR3

References1. S. Komiya, Coordination Chemistry Review, 256, 556 (2012).2. A. Kuramoto,K. Nakanishi, T. Kawabata, N. Komine, M Hirano, and S. Komiya, Organometallics, 25, 311, (2006).3. N. Komine, A. Kuramoto, K. Nakanishi, M. Hirano, and S. Komiya, Top. Catal., in press.

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O-D4-05-03

SELECTIVE RHODIUM-CATALYZED REDUCTION OF TERTIARY AMIDES IN AMINO ACID ESTERS AND PEPTIDES

Shoubhik Das1, Kathrin Junge1, Matthias Beller *1

Leibniz-Institut für Katalyse e.V., Albert-Einstein Straße 29a, Rostock, 18059, Germany.Presenting Author: [email protected]

In recent years, peptide derivatives are gaining increasing attention for the development of novel pharmaceuticals due to their lower toxicity and exquisite binding specificty.1 The major concern for this peptide based drugs are their poor bioavailability, owing to the susceptibility of amide bonds toward hydrolysis by peptidases.2 In this respect, especially structural modifications of the different carbonyl groups are decisive. For example, Lever and co-workers demonstrated a 2,000-fold increase in renin inhibition through the reduction of one amide bond in a peptidomimetic inhibitor.3 In addition to heightened potency, the amine of the aminomethylene group is positively charged at neutral pH, providing the peptide with a flexible hydrogen bond donor. This simple modification is known to impart global and local changes to the peptide dipole moment, potentially affecting the pharmacological properties such as oral bioavailability and membrane permeability and thereby enhances therapeutic effectiveness.

NO

OO

*

N

OO

*N

O

N

Cyclosporine A, immunosuppressant drugshows poor bioavailability

Selective reduction of tertiary amide, Improved bioavailability

30% isolated yield, 6 g scale

or or[Rh(cod)2]BF4] (1

.5 mol%)

dppp/ PhSiH3/ THF/

rt-40°C

N

O

O

HNCO2Et*

*N

O

O

HNCO2Et*

* N

O

O

HNCO2Et

S

*

*

OO

N

HN

NH

O

O

O

(82%)

NH

ON

NH

ONH

OO

O

O

(60%)

* ** *

O

O

N

O

HN

O

ON

O

HN

O

NH

N

OO

N

ON

O

NO

O

NH

O

N

OH HH

H

Amide from Sarcosine

Amide from Proline

(85%)(78%) (80%)

Unfortunately, to the best of our knowledge there exists no general methodology for selective reductions of specific amide bonds in peptides. So herein, we have reduced very selectively the tertiary amide bonds from proline and sarcosine in presence of other amide bonds from different amino acids in a long peptide chain.6 Interestingly, the catalyst was highly selective for the selective reduction of amide bond in cyclosporine A. We believe, by combining the advantages of automated peptide synthesis with such selective reductions, a multitude of novel peptide derivatives for chemical biology studies as well as potential pharmaceutical applications will be available.

References:1. D. J. Craik, D. P. Fairlie, S. Liras, D. Price, Chem. Biol. Drug. Des. 81, 136 (2013).2. M. G. Bursavich, D. H. D. Rich, J. Med. Chem. 45, 541 (2002).3. M. Szelke, B. Leckie, A. Hallett, D. M. Jones, J. Sueiras, B. Atrash, A. F. Lever, Nature, 299, 555 (1982).

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O-D4-05-04

Direct Electrophilic Trifluoromethylation of Quinolones and Pyridones

Remo Senn, Antonio Togni a) *

a) Department of Chemistry and Applied Biosciences, ETH Zürich,Vladimir-Prelog-Weg 2, 8093 Zürich

*[email protected]

Since their discovery in the late 70’s quinolone based antibiotics belong to the most prescribed broad-spectrum antibacterial drugs. [1] Especially compounds based on the fluoroquinolone core struc-ture like Norfloxacin, Ciprofloxacin, Ofloxacin have found extensive application in treating various infectious diseases. [2]

Although a myriad of compounds were evaluated to further optimise their antibacterial activity and pharmacokinetic properties, N-trifluoromethylated fluoroquinolones still represent a rarity. [3] This is mainly due to the fact that the only known procedure to access such compounds relies on oxidative desulfurisation-fluorination. [4]

Recently, we reported the direct electrophilic N-trifluoromethylaton of a variety of nitrogen con-taining heterocycles, such as tetrazoles, triazoles, indazoles and pyrazoles [5] using the hypervalent iodine reagent 1, originally developed in our group. [6]

After in situ trimethylsilylation, similar conditions were examined with a variety of quinolones and pyridones, which were thus converted to the corresponding O-trifluoromethylated species in good yield and functional group tolerance. Mechanistic investigations involving 19F- and 29Si-NMR 2D spec-troscopy and competition experiments, revealed a reaction mechanism featuring complex pre-equilib-ria.

[1] H. Koga, A. Itoh, S. Murayama, S. Suzue, T. Irikura, J. Med. Chem., 23 (1980) 1358-1363.[2] V. T. Andriole (Ed.) The quinolones, Third Edition, Academic Press, 2000. [3] Y. Asahina, I. Araya, K. Iwase, F. Iinuma, M. Hosaka, T. Ishizaki, J. Med. Chem., 48 (2005) 3443-3446.[4] M. Kuroboshi, T. Hiyama, Tet. Lett., 33 (1992) 4177-4178.[5] K. Niedermann, N. Früh, R. Senn, B. Czarniecki, R. Verel, A. Togni, Angew. Chem. Int. Ed., 51 (2012) 6511-6515.[6] P. Eisenberger, S. Gischig, A. Togni, Chem. Eur. J., 12 (2006) 2579-2586.

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O-D4-05-05

Sulfur Atom Transfer (SAT) Reaction and Synthesis of Sulfur-Containing Drugs and Natural Products

Xuefeng Jiang

Shanghai Key Laboratory of Green Chemistry and Chemical Process, Department of Chemistry, East China Normal University, 200062, Shanghai, China

Csp3-I bond, especially those with β-hydrogen atoms, are a class of challenging substrates for the palladium-catalyzed transforms owing to the facile β-H elimination for alkylpalladium intermediate. Herein, Pd-catalyzed reactions from unactivated Csp3-I bond were disscussed. Reaction a displays a Pd-catalyzed atom transfer cyclization of unactivated alkyl iodide.1 Reaction b provides a Pd-catalyzed reductive cross-coupling protocol without metallic reductant.2 Reaction c shows a Pd-catalyzed double intramolecular C-S bond formation coupling reaction by using Na2S2O3 as sulfurating reagent.3 Reaction d demonstrate various aryl derivatives could achieve the intermolecular dual C-S bonds constructing reactions,4 which are excellent strategies for drug late stage sulfuration. When sodium sulfuinates were introduced into the sulfur atom transfer system, desired S-S bonds were formed (reaction e),5 which will be applied in the total synthesis of natural products, such as Epicoccin A, C, D bearing S and S-S bridge. Besides, aerobic oxidative C-C bonds cleavage was systemtied studied.6

I

RNa

2S2O3

R'XNTs

IR

NTs

R

NTs

I I

R

NTs

NH2

R

S

RR'

SONa

O

R

R' S

S RR

I

+

S

NTs

R

sp3-I Bond

OA Sulfur Atom

Transfer

Epicoccin A

x=2, y=1Epicoccin

C

x=2, y=2Epicoccin

D

x=1, y=1

Sulfur-Containing Natural

Products

N

OHH

HO N

O

O

O

HO

H

H

Sx

Sy

a b d ecX

R

Reference1. (a) Liu, H.; Qiao, Z.; Jiang, X. Org. Biomol. Chem. 2012, 10, 7274. (b) Jiang, X.; Liu, H.; Gu, Z. Asian J. Org. Chem. 2012, 1, 16. (c) Liu, H.; Jiang, X. Pure and Applied Chemistry 2014, 86, 307.2. Liu, H.; Wei, J.; Qiao, Z.; Fu, Y.; Jiang, X. Chem. Eur. J. 2014, 20, 10.1002/chem.201403093.3. (a) Qiao, Z.; Liu, H.; Xiao, X.; Fu, Y.; Wei, J.; Li, Y.; Jiang, X. Org. Lett. 2013, 15, 2594. (b) Liu, H.; Jiang, X. Chem. Asian J. 2013, 2546.4. (a) Qiao, Z.; Wei, J.; Jiang, X. Org. Lett. 2014, 16, 1212; (b) Li, Y.; Pu, J.; Jiang, X. Org. Lett. 2014, 16, 10.1021/ol5009747.5. (a) Xiao, X.; Jiang, X. submitted.6. (a) Liu, H.; Jiang, X. Synlett, 2013, 24, 1311; (b) Liu, H.; Dong, C.; Zhang, Z.; Wu, P.; Jiang, X. Angew. Chem. Int. Ed. 2012, 51, 12570.

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O-E1D3-01-02

MULTI-FUNCTIONAL BISPIDINE DERIVATIVES AS VERSATILE IMAGING AGENTS

H. Stephan1, P. Comba2

1Helmholtz-Zentrum Dresden-Rossendorf, Institute of Radiopharmaceutical Cancer Research, D-01314, Dresden, Germany

2Universität Heidelberg, Anorganisch-Chemisches Institut, D-69120, Heidelberg, GermanyPresenting author: [email protected]

The development of multi-functional complexing agents for radiometal nuclides with a view of nuclear medical application represents a fast developing field of intensive research [1]. A requirement for ligands in this field is fast complexation kinetics and high complex stabilities with specific radiometal ions and ligands which are easy to functionalize with several different groups for linking to biological vectors, nanoparticles and/or fluorescence molecules.

Ligands based on 3,7-diazabicyclo[3.3.1]nonane (bispidine) form very stable transition metal complexes [2]. Due to the formation of thermodynamically and kinetically stable CuII complexes, pentadentate and hexadentate bispidines are very well suited for in vivo application, i.e. for tumor imaging (64CuII) using positron emission tomography (PET) and tumor therapy (64CuII, 67CuII) [3, 4]. The bispidine scaffold has various sites for functionalization that permit the introduction of biomolecules for pharmaceutical targeting and fluorescent units for optical imaging (see Figure 1).

Several bispidine ligands have been developed in order to improve the radiopharmaceutical behavior as well as possibilities for further beneficial functionalization. These ligands and the important properties of their CuII complexes, e.g., stabilities, ligand exchange kinetics, serum stability, partition coefficients ([64Cu]Cu-bispidine: n-octanol/water) and biodistribution studies 64Cu-labeled bispidines will be reported.

References1. C. S. Cutler, M. H. Hemmkens, N. Sisay, S. Markai-Huclier. S. S. Jurisson, Chem. Rev. 113, 858

(2013).2. P. Comba, M. Kerscher, W. Schiek, Prog. Inorg. Chem. 55, 613 (2007).3. S. Juran, M. Walther, H. Stephan, R. Bergmann, J. Steinbach, W. Kraus, F. Emmerling, P. Comba,

Bioconjugate Chem. 20, 347, (2009).4. P. Comba, S. Hunoldt, M. Morgen, J. Pietzsch, H. Stephan, H. Wadepohl, Inorg. Chem. 52, 8131

(2013).

Figure 1: Bispidine scaffold for targeted dual imaging.

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O-E1D3-01-03

Sensing Membrane Fluidity with Fluorescent Molecular Flippers

M. Dal Molin, N. Sakai, S. Matile

University of Geneva, Department of Organic Chemistry, 1211, Geneva, SwitzerlandPresenting author: [email protected]

Recently our group proposed the use of a new class of bioinspired fluorescent probes based on amphiphilic oligothiophene push-pull systems that exploits a combination of planarization and polarization of the oligothiophene scaffold for the sensing of membrane polarization, fluidity, homogeneity and tension [1]. The extensive exploration of the structure-properties relationships revealed that the nature of the push-pull moieties, the length of the oligothiophene system and the degree and positioning of twisting units are all key features in the design of the perfect probe [2].

We now propose an innovative design where the oligothiophene units in the dye core are substituted by highly fluorescent dithienothiophene-S,S-dioxide moieties [3]. In this new configuration, the mechanosensitivity is improved by the enhanced contact area offered by the extended π system, similarly to the effect of diving flippers (Fig.1). Moreover, the choice of the intrinsically fluorescent moieties as torsional unit prevents the loss of quantum yield occurring after the probe deplanarization.

Figure 1: Compared to the original probe 1 (left), the new probe based on fluorescent molecular flippers 2 (right) offers better mechanosensitivity and higher quantum yield.

References1. Fin, A.; Vargas Jentzsch, A.; Sakai, N.; Matile, S. Angew. Chem. Int. Ed. 2012, 51, 12736-12739.2. a) Dal Molin, M.; Matile, S. Org. Biomol. Chem. 2013, 11, 1952-1957. b) Alonso Doval, D.; Matile,

S. Org. Biomol. Chem. 2013, 11, 7467-7471. c) Alonso Doval, D.; Dal Molin, M.; Ward, S.; Fin, A.; Sakai, N.; Matile, S. Chem. Sci. 2014, in press.

3. Palamà, I.; Di Maria, F.; Viola, I.; Fabiano, E.; Gigli, G.; Bettini, C.; Barbarella, G. J. Am. Chem. Soc. 2011, 133, 17777-17785.

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O-E1D3-01-05

BORONIC ACID PROBES FOR ENZYME ASSAYS AND MOLECULAR COMPUTING

A. Schiller

Friedrich Schiller University Jena, Humboldtstr. 8, 07743 Jena, [email protected]

Indicator displacement assays (IDAs) represent an elegant approach in supramolecular analytical chemistry.[1,2] A chemical biosensor for the selective detection of the cyano genic glycoside amygdalin in aqueous solution is reported.[3] The hybrid sensor con sists of the enzyme β-glucosidase and a boronic acid appended viologen together with a fluorescent reporter dye.[1-6] β-Glucosidase degrades the amygdalin into hydrogen cyanide, glucose, and benzaldehyde. Only the released cyanide binds at the allosteric site of the boronic acid receptor thereby inducing changes in the affinity of a formerly bound fluorescent indicator dye at the other side of the receptor. Thus, the sensing probe performed as allosteric indicator displacement assay (AIDA) for cyanide in water. Further, the sensing system has been used in molecular logic. The AIDA probe repre sents the logic gate implication (IMP). Switching between 0 and 1 was monitored on a confocal microscope using fluorescence correlation spectroscopy on the few-molecule level of the reporting dye.[5] With the help of the IMP gate, a „sugar computer“ on micro titer plates was generated for number crunching.[6]

References:[1] D. A. Jose, A. Ghosh, A. Schiller, in Discovering the future of molecular sciences (Ed.: B. Pigna-taro), Wiley-VCH, Weinheim, 2014. [2] A. Schiller, in Molecules at Work. Selfassembly, Nano-materials, Molecular Machinery (Ed.: B. Pignataro), Wiley-VCH, Weinheim, 2012, 315. [3] D. A. Jose, M. Elstner, A. Schiller, Chem. Eur. J. 2013, 19, 14451. [4] A. Schiller, R. A. Wessling, B. Sin-garam, Angew. Chem., Int. Ed. 2007, 46, 6457. [5] M. Elstner, K. Weisshart, K. Müllen, A. Schiller, J. Am. Chem. Soc. 2012, 134, 8098. [6] M. Elstner, J. Axthelm, A. Schiller, Angew. Chem., Int. Ed. 2014, DOI: 10.1002/anie.201403769.

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O-E1D3-01-06

LUMINESCENT SILICA NANOPARTICLES CARRIERS: SYNTHESIS, OPTICAL PROPERTIES AND SINGLET OXYGEN GENERATION

E. Gianotti1, B. Martins Estevao1, F. Cucinotta1, N. Hioka2, L. Marchese1

1Dipartimento di Scienze e Innovazione Tecnologica, Centro Nano-SiSTeMI, Università del Piemonte Orientale, Via T. Michel 11, 15100, Alessandria, Italy

bNucleos Research of Photodynamic Therapy, Chemistry Department, State University of Maringá, Av. Colombo 5.790, 87020-900, Maringá, Paraná, Brazil.


Functionalized mesostructured silica nanoparticles have been studied and tested for a wide range of biological, biomedical and technological applications. In several studies, mesoporous nanoparticles were used as carriers for drug delivery and, more recently, these materials have been exploited for hosting organic fluorophores to obtain a new class of hybrid materials with potential applications as solid lasers, optical sensors, cellular imaging and in photodynamic therapy (PDT). In particular, PDT is an emerging treatment for a variety of oncological, cardiovascular, dermatological and ophthalmic diseases1. PDT is based on the concept that photosensitizer (PS) generate singlet oxygen (1O2) upon irradiation, which acts as cytotoxic agent responsible for irreversible damage of the treated tissues. This treatment offers the advantage of an effective and selective method of destroying diseased tissues without damaging adjacent healthy ones. To avoid the release, it is necessary to incorporate covalently the PS within biocompatible delivery vehicles. Among the various vehicles, mesoporous silica nanoparticles (MSNs) have attracted great scientific interest due to the high in vivo biocompatibility, straightforward surface functionalization and avid cell uptake2.In this contribution, we report a simple surface modification that conjugates a photosensitizer, a xanthene dye or porphyrin, with amino-functionalized MSNs through covalent bonding to yield luminescent MSNs for PDT study3. Several hybrid systems with different dye loading were prepared to optimize the photosensitizer concentration and to obtain a high efficiency of 1O2 release. A detailed structural and morphological characterization of the hybrids by using XRD, HRTEM, volumetric and thermogravimetric analysis combined with spectroscopic characterization by using DR UV-Vis, FTIR, SS-NMR and photoluminescence spectroscopies will be presented. The 1O2 generation will be evaluated by using uric acid, which reacts irreversibly with 1O2. These hybrid materials represent the first step in the design of multifunctional nanoplatforms for cancer theranostics (imaging, targeting and therapy).

References1. J.P. Celli, B.Q. Spring, I. Rizvi, C.L. Evans, K.S. Samkoe, S. Verma, B.W. Pogue, T. Hasan, Chem.

Rev. 110 (2010) 2795. 2. M. Colilla, B. Gonzales, M. Vallet-Regi, Biomater. Sci., 1 (2013) 114 3. E. Gianotti, B. Martins Estevão, F. Cucinotta, N. Hioka, L. Marchese, Nanoscale, submitted.

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O-E1D3-02-03

MRI evaluation of tumor Hypoxia in murine xenograft mammalian tumors by using Gd-DOTP- and Gd-HPDO3A- labeled Red Blood Cells

E. Gianolio1, E. Di Gregorio1, G. Ferrauto1 S. Lanzardo1, S. Aime.1

1Dep. of Molecular Biotechnologies and Health Sciences, University of Torino, 10126,Torino,Italy

Assessment of hypoxia is crucial for several major diseases and much attention is currently devoted to the development of imaging probes able to monitor the oxygenation state of tissues. Different methods to evaluate pO2 have been developed based on the use of different imaging modalities. Herein, the in vitro development and in vivo application of a novel procedure for hypoxia evaluation by MRI is described. This method relies on the use of Gd-DOTP-labeled Red Blood Cells as probes responsive to the oxygenation state and Gd-HPDO3A-labeled RBC as probe reporting on the vascular volume. The application of a ratiometric method to analyze the MR images allows obtaining semi-quantitative measurements of tumor oxygenation state with a high spatial resolution. The affinity constants (Ka) of Gd-DOTP to oxy- and deoxy-Hb have been determined by the Proton Relaxation Enhancement method. Gd-DOTP, analogously to the natural allosteric effector BPG, displays higher affinity toward deoxy-Hb than to oxy-Hb. The increase in relaxivity obtained upon binding to deoxy-Hb is significantly higher than that observed when Gd-DOTP is bound to oxy-Hb. More insights have been obtained by acquiring the NMRD profiles of Gd-DOTP- and Gd-HPDO3A- loaded RBCs both in oxygenated and deoxygenated environment. As the relaxivity of Gd-HPDO3A does not display any dependence upon oxy-Hb/deoxy-Hb ratio, Gd-loaded RBC can be used to assess vascular volume. On this basis it has been possible to assess tumor hypoxia by acquiring T1w maps of the tumor region pre and post the injection of Gd-HPDO3A and Gd-DOTP labelled-RBCs in mice tumors. This approach is useful to relate tumour development and hypoxic regions at the high spatial resolution provided by MRI.as well as for the stratification of patients in respect to therapies that are not efficacious in the absence/low concentration of oxygen.

Figure 1: Ka and R1-bound values (B) for Gd-DOTP (A) with oxy- or deoxy-Hb obtained through Relaxometric Titrations (C). D) Representative images of vascular volume and deoxygenation maps in the tumor region at different stages of progression.

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O-E1D3-02-05

Uptake of Dexamethasone in Human Skin Investigated by Soft-X-Ray Spectromicroscopy

E. Rühl1, K. Yamamoto1, T. Ohigashi2, R. Flesch1, P. Patoka1, G. Ulrich1, S. Ahlberg3, F. Rancan3, A. Vogt3, U. Blume-Peytavi3, P. Schrade4, S. Bachmann4, R. Haag5, E. Fleige5, S. Küchler6, M. Schäfer-

Korting6, N. Kosugi2 1 Physical Chemistry, Freie Universität Berlin, 14195 Berlin, Germany

2 Institute for Molecular Science, 444-8585,Myodaiji, Okazaki, Japan 3 Klinisches Forschungszentrum für Haut- und Haarforschung, Charité Universitätsmedizin, 10117

Berlin, Germany 4 Abteilung für Elektronenmikroskopie at CVK, 13353 Berlin, Germany5 Organic Chemistry, Freie Universität Berlin, 14195 Berlin, Germany

6 Institut für Pharmazie, Freie Universität Berlin, 14195 Berlin, Germany Presenting author: [email protected]

The uptake of the anti-inflammatory drug dexamethasone into human skin is probed by soft-X-ray spectromicroscopic techniques. They serve for quantifying the uptake and transport of drugs into skin by label-free approaches.

The experiments were carried out at the UVSOR storage ring (Institute for Molecular Science, Okazaki, Japan). Excised human skin was exposed to dissovled dexamethasone and vertical slices were investigated using a scanning transmission X-ray microscope (STXM). The spectral resolving power of 6000 enables us to take two-dimensional (2-D) near edge X-ray absorption fine structure (NEXAFS) images with a lateral resolution of ca. 100 nm. These results are obtained from detecting the intensity of the transmitted soft X-rays while scanning the samples in two dimensions.

Dexamethasone is probed by the intense near-edge resonances occurring near the oxygen K-edge (530-545 eV). 2-D images are taken on and off these resonances in the presence of dexamethasone, so that vertical profiles of the drug penetration are derived. The results indicate that dexamethasone is mostly present in the outermost layer of the viable epidermis and in the horny layer of skin (stratum corneum).

Additionally, experiments were carried out where the uptake of dexamethasone by polymeric nanocarriers, which are known to enhance dermal drug uptake, is studied by near-edge spectroscopy. This also allows us to quantify the uptake efficiency of dexamethasone into drug nanocarriers by X-ray absorption as well as the drug penetration and the penetration profile in human skin.

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O-E1D3-02-05

SUPERFLUORINATED PROBES FOR HIGHLY SENSITIVE IN VIVO 19F-MRI

I. Tirotta1,2, C. Pigliacelli1,2, G. Resnati1,2, P. Metrangolo1,2,3, F. Baldelli Bombelli1,2,4

1 Laboratory of Nanostructured Fluorinated Materials (NFMLab), Department of Chemistry, Materials, and Chemical Engineering “Giulio Natta”, Politecnico di Milano, Milan, Italy

2 Fondazione Centro Europeo Nanomedicina, Milan, Italy3 VTT-Technical Research Centre of Finland, Espoo, Finland

4 School of Pharmacy, University of East Anglia, Norwich, UK Presenting author: [email protected]

With his high natural abundance, characteristic resonance properties, and its negligible presence in the human body, fluorine is a perfect candidate for in vivo MRI. [1] In the past ten years many studies reported on the use of 19F-MRI in the diagnosis and treatment of various diseases.[2] Several fluorous reporter agents have been used, mostly consisting of liquid perfluorocarbons (PFC) or perfluoropolyethers (PFPE) administered as nano formulations. In this communication we wish to report the synthesis and full characterization of a novel 19F-MRI reporter (FR) consisting of a single highly fluorinated symmetrical molecule and its facile and scalable formulation in water, which yields a stable and monodisperse nanoemulsion of an averaged particle size of 150-210 nm, allowing for the dispersion in water of up to 75 mg/ml of FR. The unique structure of FR results in a single, very intense 19F-NMR peak, which ensures facile identification of the reporter and avoids artefacts formation, particularly in MRI experiments. Biocompatibility was evaluated in vitro on two different cell cultures showing no cytotoxicity and excellent survival rate. Finally both in vitro and in vivo 19F-MRI experiments showed very low detection limits, short acquisition time, and good detectability in vivo, even for small number of cells [1]. Moreover, a modified version of FR and other fluorinated ligands were attached to the surface of gold nanoparticles (NP), which were further functionalized to be dispersable in aqueous solutions forming stable nanostructures of about 150 nm. Given the versatile chemical structure of such NPs, we forecast their use as innovative theranostic agents for drug delivery. These promising results may pave the way to different fluorinated multifunctional nanostructures, allowing several in vivo applications, which are under current investigation in our laboratory.

Figure 1: A) Crystallographic structure of the FR. B) Photo of the nanoemulsion containing FR. C) In vivo 19F-MRI of 19F-labeled DCs (5 mg/mL of FR), where 5 x 106 DCs were injected subcutaneously (s.c.) in the right popliteal area (right leg) of a naive Lewis rat.

References1) Ruiz-Cabello, J. et al., NMR Biomed 24, 114 (2011)2) Du, W et al., Bioconj Chem 19, 2492 (2008)

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O-E1D3-03-02

Hybrid imaging tracer for the specific imaging of bacterial infections

A. Bunschoten1, M. M. Welling1, F.W.B. van Leeuwen1

1Department of Radiology, Interventional Molecular Imaging Laboratory, Leiden University Medical Center, Leiden, the Netherlands.


Specific and sensitive molecular imaging of bacterial infections can aid in the clinical diagnostic pro-cess and selection of the most optimal treatment. As in clinical decision making the distinction between a bacterial infection and a sterile inflammation can be crucial, a selective tracer is required. However, only a limited number of agents are available for the detection and localization of infections.[1]Previously, we developed a radioactively labeled version of the synthetic antimicrobial peptide UBI29-

41.[2] This peptide was successfully evaluated in clinical studies for imaging various types of infec-tions.[3] A hybrid derivative of UBI29-41, containing both a fluorescent and radioactive label, could enable specific detection and localization of bacteria using non-invasive imaging modalities (SPECT/PET) and would aid in the detection (optical imaging) and removal of these bacterial infections during surgical interventions.[1]Here we report on the synthesis of a hybrid derivative of UBI29-41. To this end a hybrid label, consist-ing of a DTPA-chelate for the introduction of 111-In and a Cy5 fluorescent dye, was conjugated to the antimicrobial peptide. Binding efficacy of the hybrid tracer to various bacterial strains (S. aureus, S. epidermidis, K. pneumoniae, E. coli and B. subtilis) was evaluated after labeling with 111In. Uptake in the bacteria was visualized using fluorescence confocal microscopy and quantified by gamma counting.In vivo infection imaging, using both microSPECT and fluorescence imaging was evaluated in mice inoculated with either S. aureus or K. pneumonia in the thigh or front paw. Imaging was performed at 1, 2 and 24 h post injection of the hybrid tracer. Fast excretion via the kidneys (72-93 %ID) was observed and target to non-target ratios (T/NT) were optimal at 2 h post injection (3.0±1.1 for S. aureus and 2.7±0.6 for K. Pneumoniae).These results show that combined diagnostic and intraoperative imaging of bacterial infections is possi-ble using a hybrid derivative of the antimicrobial peptide UBI29-41. The integration of diagnostic nuclear imaging and optical guidance during surgical interventions that is achieved via this method is expected to help optimize the current treatment strategies.References1. A. Bunschoten, Bioconjug. Chem. 24(12): 1971-89 (2013).2. P.H. Nibbering, J. Nucl. Med. 45(2): 321-6 (2004).3. C. Arteaga de Murphy, Nucl. Med. Comm. 31(8): 726-33 (2010).

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O-E1D3-03-03

CYCLAM WITH N-CARBOXYETHYL PENDANT ARMS AS SUITABLE RADIOCOPPER CHELATES

M. Kubeil1, K. Zarschler1, J. Pietzsch1,2, H. Stephan1, P. Comba3.1Helmholtz-Zentrum Dresden-Rossendorf, Instiute of Radiopharmaceutical Cancer Research, 01314,

Dresden, Germany2Technische Universität Dresden

Fachrichtung Chemie und Lebensmittelchemie, 01062, Dresden, Germany3Universität Heidelberg, Anorganisch-Chemisches Institut, 69120, Heidelberg, Germany


Cyclam (1,4,8,11-Tetraazacyclotetradecane) and its derivatives are powerful ligands for very stable complexes with (radio)copper(II) [1]. These chelators allow the functionalization of targeting molecules, e.g. peptides and/or fluorescence units, to construct effective radiopharmaceuticals for diagnostic and therapeutic purposes. In this context, 1,4,8,11-tetra(carboxymethyl)-1,4,8,11-tetraazacyclotetradecane (TETA) is used for the development of copper-based target-specific radiopharmaceuticals, although dissociation and transchelation occur in biological systems. In contrast, radiolabeling of the pentadentate cyclam ligands with a different number of N-carboxyethyl groups have not been reported so far. As a consequence, their copper(II) complexes have been synthesized [2]. Herein, we present a comprehensive study, dealing with the influence of the pendant arm length on structural properties, radiolabelling conditions, in vitro and in vivo stability, and compare these results with cyclam ligands bearing N-carboxymethyl pendant arms e.g., CuII-TETA.

NH

N

N

N OHHO

O O

OH

O

NH

N

N

HNHO

O

OH

O

N

N

N

N OHHO

O O

OH

O

NH

NH

N

HN

OH

O

HO

O

TE1P trans-TE2P TE3P TETP

Figure 1: Structures of cyclam derivatives bearing a different number of N-carboxyethyl pendant arms

The different number of N-carboxyethyl pendant arms at the cyclam backbone strongly influences the structure and stability of the copper complexes. TE2P is ideally suited as a copper(II)-chelating agent due to its fast complexation with radiocopper, the high kinetic inertness towards SOD and human serum as well as the excellent biodistribution behaviour. The facile N-functionalization of TE2P with a specific peptide produces an imaging tool with improved pharmaceutical targeting.

References1. T. J. Wadas, E. H. Wong, G. R. Weisman, C. J. Anderson, Chem. Rev. 110, 2858 (2010).2. P. Comba, F. Emmerling, M. Jakob, W. Kraus, M. Kubeil, M. Morgen, J. Pietzsch, H. Stephan, Dalton Trans. 42, 6142 (2013).

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O-E1D3-03-04

FLUORESCENT LABELING OF CARBON NANOTUBES

Özge Çavuşlar1, Hayriye Ünal2 1Material Science and Engineering Department, Sabancı University, İstanbul 34956, Turkey

2Sabancı University Nanotechnology Research and Application Center, Sabancı University İstanbul, 34956, Turkey


Asymmetric cyanine dyes are widely used for the labeling and detection of nucleic acids as their low background fluorescence increases several fold upon intercalating into DNA and RNA. While asym-metric cyanine dyes have been investigated thoroughly in terms of their interactions with biomol-ecules, their interactions with CNTs have yet not been extensively researched. However, results of experimental and theoretical studies on both carbon nanotubes and cyanine dyes suggest that hybrid materials formed by the interactions of these two will have novel properties. Here, we investigated the interactions of CNTs and DNA wrapped CNTs with asymmetric cyanine dye molecules to study the applicability of resulting hybrid materials to fluorescent based systems.Dispersion studies where asymmetric cyanines are used as dispersing agent for CNTs and Raman spec-troscopy indicate strong noncovalent interactions between the dyes and CNTs. These noncovalent bind-ing interactions were studied for a panel of asymmetric cyanine dyes and CNTs (single walled/multi walled/double walled) to understand the effect of dye and CNT structure on noncovalent interactions and optical properties. We also studied the interactions of asymmetric cyanine dyes on CNTs that are wrapped with single stranded DNA oligomers. Strong noncovalent interactions have been confirmed which also lead to activation of asymmetric cyanine dye fluorescence. Systematic studies on the in-teractions of asymmetric cyanine dyes with CNTs as a method to fluorescently label CNTs for optical visualization will be presented.

FLUORESCENT LABELING OF CARBON NANOTUBES

Özge Çavuşlar1, Hayriye Ünal2 1Material Science and Engineering Department, Sabancı University, İstanbul 34956,

Turkey 2Sabancı University Nanotechnology Research and Application Center, Sabancı

University İstanbul, 34956, Turkey Presenting author: [email protected]

Asymmetric cyanine dyes are widely used for the labeling and detection of nucleic acids as their low background fluorescence increases several fold upon intercalating into DNA and RNA. While asymmetric cyanine dyes have been investigated thoroughly in terms of their interactions with biomolecules, their interactions with CNTs have yet not been extensively researched. However, results of experimental and theoretical studies on both carbon nanotubes and cyanine dyes suggest that hybrid materials formed by the interactions of these two will have novel properties. Here, we investigated the interactions of CNTs and DNA wrapped CNTs with asymmetric cyanine dye molecules to study the applicability of resulting hybrid materials to fluorescent based systems.

Dispersion studies where asymmetric cyanines are used as dispersing agent for CNTs and Raman spectroscopy indicate strong noncovalent interactions between the dyes and CNTs. These noncovalent binding interactions were studied for a panel of asymmetric cyanine dyes and CNTs (single walled/multi walled/double walled) to understand the effect of dye and CNT structure on noncovalent interactions and optical properties. We also studied the interactions of asymmetric cyanine dyes on CNTs that are wrapped with single stranded DNA oligomers. Strong noncovalent interactions have been confirmed which also lead to activation of asymmetric cyanine dye fluorescence. Systematic studies on the interactions of asymmetric cyanine dyes with CNTs as a method to fluorescently label CNTs for optical visualization will be presented.

Figure 1: CNT wrapped with DNA becomes fluorescent when labeled with the cyanine dye Figure 1: CNT wrapped with DNA becomes fluorescent when labeled with the cyanine dye

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O-E1D3-03-05

OPTIMIZATION AND RADIOLABELING OF ULTRASMALL UPCONVERTING NANOPARTICLES FOR MULTIMODAL CANCER IMAGING

J. Hesse1, B. Graham2, G. Geipel3, J. Grenzer4, R. Hübner4, L. Spiccia5, J. Steinbach1, H. Stephan1

1 Helmholtz-Zentrum Dresden-Rossendorf (HZDR), Institute of Radiopharmaceutical Cancer Re-search, 01328, Dresden, Germany. 2 Monash University, Monash Institute of Pharmaceutical Scienc-es, 3052, Melbourne, Australia. 3 HZDR, Institute of Resource Ecology, 01328, Dresden, Germany. 4 HZDR, Institute of Ion-Beam Physics and Materials Research, 01328, Dresden, Germany. 5 Monash

University, School of Chemistry, 3800, Melbourne, Australia. Email: [email protected]

In recent years, multimodal imaging has obtained increasing attention since it is an attractive strategy to com-bine the advantages of different imaging modalities, aiming to enhance the efficiency and sensitivity of disease diagnosis and imaging of treatment progress. In this context, nanoparticles come to the fore due to their diversity and versatility. Depending on the material used, nanoparticles themselves can already constitute an imaging probe because of magnetic and/or fluorescence properties which enable magnetic resonance (MR) or optical imaging. In addition, they offer the opportunity for multiple functionalization to introduce additional labels and biospecific molecules on their surface. Nanoparticles of particular interest are the so-called “upconverting nanophosphors” (UCNPs). With their exceptional ability to convert near-infrared to visible light (upconversion), these inorganic lanthanide-doped nanoparticles are very attractive for biomedical applications. Their excitation in an optical transparency window (the “biological window” between 700-1000 nm) enables deep penetration into tissue, as well as high contrast related to minimum autofluorescence in this spectral range. Furthermore, these materials have shown no inherent toxicity effects in both in vitro and in vivo studies. Known syntheses of UCNPs generate mainly hydrophobic particles. However, there are several possibilities to achieve biocompati-bility by applying different coating strategies [1]. Here, we discuss the synthesis and photophysical properties of ultrasmall (<10 nm) UCNPs based on a host lattice of nanocrystalline NaYF4 doped with Yb3+ as a sensitizer, as well as Er3+ or Tm3+ as emitter ions with an excitation wavelength at 980 nm. Additionally, by insertion of Nd3+ as a primary sensitizer, the excitation wavelength can be changed to 795 nm, resulting in deeper tissue penetration and lower heating effects associated with water absorption in the range of 1000 nm. Furthermore, by using an active shell strategy, quenching effects can be reduced. The most appropriate UCNPs were coated with amphiphilic polymers in order to achieve highly colloidally-stable, wa-ter-dispersible systems suitable for biomedical applications. In this way, further functionalization with targeting vector molecules and the intro-duction of bifunctional chelators is possible. By way of demonstration, a dipicolyl derivative of 1,4,7-triazacyclononane has been coupled as a radiocopper chelator to allow for 64Cu-based positron emission tomogra-phy [2].

References

1. G. Chen, H. Qiu, P. N. Prasad and X. Chen, Chem. Rev. (2014), DOI: 10.1021/cr400425h.

2. K. Pombo-García, K. Zarschler, J. A. Barreto, J. Hesse, L. Spiccia, B. Graham and H. Stephan, RSC Adv. 3, 22443 (2013).

OPTIMIZATION AND RADIOLABELING OF ULTRASMALL UPCONVERTING NANOPARTICLES FOR MULTIMODAL CANCER IMAGING

J. Hesse1, B. Graham2, G. Geipel3, J. Grenzer4, R. Hübner4, L. Spiccia5, J. Steinbach1, H.

Stephan1 1 Helmholtz-Zentrum Dresden-Rossendorf (HZDR), Institute of Radiopharmaceutical Cancer

Research, 01328, Dresden, Germany. 2 Monash University, Monash Institute of Pharmaceutical Sciences, 3052, Melbourne, Australia. 3 HZDR, Institute of Resource

Ecology, 01328, Dresden, Germany. 4 HZDR, Institute of Ion-Beam Physics and Materials Research, 01328, Dresden, Germany. 5 Monash University, School of Chemistry, 3800,

Melbourne, Australia. Email: [email protected] In recent years, multimodal imaging has obtained increasing attention since it is an attractive strategy to combine the advantages of different imaging modalities, aiming to enhance the efficiency and sensitivity of disease diagnosis and imaging of treatment progress. In this context, nanoparticles come to the fore due to their diversity and versatility. Depending on the material used, nanoparticles themselves can already constitute an imaging probe because of magnetic and/or fluorescence properties which enable magnetic resonance (MR) or optical imaging. In addition, they offer the opportunity for multiple functionalization to introduce additional labels and biospecific molecules on their surface. Nanoparticles of particular interest are the so-called “upconverting nanophosphors” (UCNPs). With their exceptional ability to convert near-infrared to visible light (upconversion), these inorganic lanthanide-doped nanoparticles are very attractive for biomedical applications. Their excitation in an optical transparency window (the “biological window” between 700-1000 nm) enables deep penetration into tissue, as well as high contrast related to minimum autofluorescence in this spectral range. Furthermore, these materials have shown no inherent toxicity effects in both in vitro and in vivo studies. Known syntheses of UCNPs generate mainly hydrophobic particles. However, there are several possibilities to achieve biocompatibility by applying different coating strategies [1]. Here, we discuss the synthesis and photophysical properties of ultrasmall (<10 nm) UCNPs based on a host lattice of nanocrystalline NaYF4 doped with Yb3+

as a sensitizer, as well as Er3+ or Tm3+ as emitter ions with an excitation wavelength at 980 nm. Additionally, by insertion of Nd3+ as a primary sensitizer, the excitation wavelength can be changed to 795 nm, resulting in deeper tissue penetration and lower heating effects associated with water absorption in the range of 1000 nm. Furthermore, by using an active shell strategy, quenching effects can be reduced. The most appropriate UCNPs were coated with amphiphilic polymers in order to achieve highly colloidally-stable, water-dispersible systems suitable for biomedical applications. In this way, further functionalization with targeting vector molecules and the introduction of bifunctional chelators is possible. By way of demonstration, a dipicolyl derivative of 1,4,7-triazacyclononane has been coupled as a radiocopper chelator to allow for 64Cu-based positron emission tomography [2].

References 1. G. Chen, H. Qiu, P. N. Prasad and X. Chen, Chem. Rev. (2014), DOI: 10.1021/cr400425h.

2. K. Pombo-García, K. Zarschler, J. A. Barreto, J. Hesse, L. Spiccia, B. Graham and H. Stephan, RSC Adv. 3, 22443 (2013).

Figure 1: Graphical representation a of multifunctionalized UCNP.

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O-E1D3-03-06

BODIPY FUNCTIONALIZED CARBON NANO-ONIONS FOR BIOLOGICAL IMAGING – COVALENT vs. NON-COVALENT APPROACHES

J. Bartelmess1, A. Signorelli1, E. de Luca2, M. Frasconi1, P. Balakrishnan3, M. Baldrighi1, T. Pellegrino3, P. P. Pompa2, L. Echegoyen4, S. Giordani.1

1Istituto Italiano di Tecnologia, Nanocarbon Materials, 16163, Genova, Italy.2Istituto Italiano di Tecnologia, IIT@UniLe, 73010, Arnesano (Lecce), Italy.

3Istituto Italiano di Tecnologia, Nanochemistry Department, 16163, Genova, Italy.4 University of Texas, El Paso, Department of Chemistry, El Paso, TX 79968, USA.


Our earlier studies of fluorescein functionalized multi-layer fullerenes, the so-called carbon nano-onions (CNOs) have shown a low cytotoxic as well as a low inflammatory potential, which renders them ideal for biomedical applications like imaging or drug delivery.[1]In the work presented here, we explored for the first time the esterification reaction of benzoic acid functionalized CNOs with meso-phenol substituted boron dipyrromethene (BODIPY) fluorophores, to create fluorescent CNO nanoparticles. In addition, we prepared fluorescent CNOs, non-covalently functionalized with novel pyrene-BODIPY dyads, where the attachment of the fluorophores to the CNO surface is accomplished by means of p-p-stacking. To our best knowledge,[2] the utilization of small molecules like pyrene for the non-covalent functionalization of CNOs has not been reported. The fluorescent CNO nanoparticles were characterized by a variety of different techniques including Raman, infrared (IR), UV-Vis absorption and fluorescence spectroscopy, thermogravimetric analysis (TGA), dynamic light scattering (DLS) and transmission electron microscopy (TEM).[3]Both, covalent CNO-BODIPY conjugates as well as non-covalent pyrene-BODIPY / CNO hybrids were successfully probed for the fluorescence imaging of different cancer cell lines with excellent results.[3]

Ongoing work in our lab focuses on the preparation of multi-functionalized CNOs incorporation imaging, targeting, and therapeutic units.

Figure 1: Schematic representation of covalently and non-covalently functionalized CNOs with BODIPY fluorophores. Center: MKF7 carcinoma cells labelled with BODIPY-CNOs.

References1. M. Yang, K. Flavin, I. Kopf, G. Radics, C. H. A. Hearnden, G. J. McManus, A. Villalta-Cerdas, L. A. Echegoyen, S.

Giordani and E. C. Lavelle Small 9, 4194-4206 (2013).2. J. Bartelmess and S. Giordani Beilstein J. Nanotechnol., submitted (2014).3. J. Bartelmess, S. Giordani, L. Echegoyen et al. manuscript in preparation (2014).

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O-E1D3-03-07

SYNTHESIS AND BIODISTRIBUTION OF 64Cu AND 68Ga RADIOLABELLED DENDRITIC POLYGLYCEROL SULFATE DERIVATIVES

K. Pant1, H. Stephan1, R. Bergmann1, J. Steinbach1, D. Gröger2, R. Haag2

1 Helmholtz Zentrum Dresden Rossendorf, D- 01314, Dresden, Germany2 Freie Universität Berlin, D-14195, Berlin, Germany


Dendrimers and their hyper-branched ouanalogues, particularly highly biocompatible polyglycerols, claim an interesting area of research due to their multivalency, simplicity in preparation and large scale one-pot .Tsynthesis. They can be modified and functionalized using manifoldmanifold strategies. Dendritic polyglycerol sulfates (dPGS) are potent substances that serve as candidates for anti-inflammatory drugs [1]. The presence of amino functionalities can be further exploited for the introduction of fluorescent dyes, drugs, radiolabels or any moiety of interest. To achieve detailed information about the in vivo fate of certain compounds, nuclear imaging techniques are the most reliable methodologies. Ex vivo imaging using 35S–isotopic labelling of these macromolecules has already been reported [2]. Positron emission tomography (PET) provides quantitative distribution datadata in vivo. The convenient detection of the emitted radiation from the inradionuclides in combination with the high sensitivity underlines the utility of nuclear imaging techniquestechniques. If a metal is used as a radiolabel, the choice of an appropriate bifunctional chelator (BFC) is the crucial point. The BFCs shall permit an easy linkage to the polymers and rapid, unsophisticated, stable labelling.

Herein, protocols for the attachment of BFCs for the positron emitting radionuclides 64Cu (t1/2 = 12.7h) and 68Ga ((t1/2 = 68 min) on dPGS scaffolds are reported. For thios reason, derivatives based on 1,4-bis(2-pyridylmethyl)-1,4,7-triazacyclononane (DMPTACN) and 1,4,7-triazacyclononane-1,4,7-triacetic acid (NOTA) equipped with suitable linker groups have been applied. Efficient radiolabelling procedures have been established (>99% RCY). The stability of the radiolabelled bioconjugates has been studied in presence of strong competing chelators (EDTA/Cyclam) as well

as in presence of HSA (human serum albumin), SOD [3] (for Cu-Conjugates) and transferrin (for Ga-conjugates). Furthermore, PET studies using Wistar rats have been performed and discussed.

References[1] J. Demedde, A. Rausch, M.Weinhart, S. Enders, R. Tauber, K. Licha, M. Schimer, U. Zugel, A. von Bonin, R. Haag, Proc. Natl. Acad. Sci. 107vol?, 19679page? (2010).[2] C. Holzhausen, D. Groger, L. Mundhenk, P. Welker, R. Haag, A. D. Gruber, Nanomed. 9, 465 page? (2013).[3] K. Zarschler, M. Kubeil, H. Stephan, RSC Adv. 4, 10157 (2014).

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O-E2-01-02

COMPUTATIONAL STUDIES OF THE RHOA GTPASE AND ACTIVATING PROTEIN RHOA.GAP – DYNAMICS AND CATALYSIS

W. Kellett1, N. Richards.1

1Chemistry and Chemical Biology, Purdue School of Science, Indiana University - Purdue University, 46202, Indianapolis, USA


GTPase enzymes, which hydrolyze guanosine triphosphate (GTP) to guanosine diphosphate (GDP) and inorganic phosphate (Pi), are involved in a large number of critical cellular processes including proliferation. GTPase Activating Protein (GAP) is responsible for the regulation of GTPase. GTPase proteins, when poorly regulated, can signal for uncontrolled cellular growth and are indicated in oncogenesis [1]. The objective of this study is to present the first complete computational model of the GTPase protein RhoA in solution and bound to the regulating protein RhoA.GAP.

Using this computational model as well as experimental insight, we study both the transition state specifically and in context of the full catalytic cycle, using Quantum Mechanics (QM) and Mixed Quantum and Molecular Mechanics (QM/MM) methodologies. Additionally, we use long-time scale MM simulations to model the protein-protein interface, and use docking methodologies to score libraries of compounds suited for interfering with this interface.

These simulations provide evidence for a dissociative transition state, pairing well with NMR data. We suggest that the MgF3

- crystallographic additive[2] is the best adduct to date to model the transition states of these types of enzymatic phosphoryl transfer reactions. These simulations also provide the first complete catalytic model of a GTPase based phosphoryl transfer mechanism. We also have identified structural effects of binding the RhoA.GAP protein to RhoA, and have preliminary results that this interface may be selectively “drug-able” based on initial compound screening. This model could be further exploited to identify ways to dissociate the errant GTPase:GAP complex by targeting the GTP binding site or even the protein-protein interface itself.

References1. Sahai, E. and Marshall, C. J. Rho-GTPases and Cancer. Nat Rev Cancer, (2002), 2, 133-142.2. Graham, D. L., Lowe, P. N., Grime, G. W., Rittinger, K., Smerdon, S. J., Gamblin, S. J., and Eccleston, J. F. MgF3

- as a Transition State Analog of Phosphoryl Transfer. Chem and Bio, (2002), 9, 375-381.

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O-E2-01-03

DEVELOPMENT OF BINDING AND ACTIVITY ASSAYS USING FLUORINATED MOLECULES

A. M. Rydzik1, I. K. H. Leung1, J. Brem1, T. D. W. Claridge1, C. J. Schofield1

1Chemistry Research Laboratory, 12 Mansfield Road, Oxford OX1 3TA, University of Oxford, United Kingdom

Presenting author: [email protected]; [email protected]

Organofluorine compounds have widespread applications in chemistry and chemical biology. In this work, methodologies for observation of enzymatic activity based on fluorine containing molecules were developed. Carnitine is an essential metabolite in human, involved in fatty acid metabolism. The last step of carnitine biosynthesis, i.e. hydroxylation of γ-butyrobetaine (GBB) to carnitine, is catalysed by γ-butyrobetaine hydroxylase (BBOX), an enzyme which belongs to the 2-oxoglutarate and Fe(II) dependent oxygenases superfamily. The synthesis of fluorinated BBOX substrate analogues provided the basis for development of assays for use in vitro with the isolated protein and in lysates, with detection by fluorescence and 19F NMR, respectively. A quantification of the fluoride ions released in a BBOX catalysed turnover of the strategically fluorinated substrate analogue (1) led to development of an assay (Fig. 1A) [1], which was used for screening of libraries of potential inhibitors, leading to discovery of an inhibitor with nanomolar potency [2]. The N-fluoromethylatated BBOX substrate analogue (2), enabled following BBOX activity in vitro and in crude cell lysates (Fig. 1B) [3]. Analogue (2) can also serve as a reporter ligand in the 19F NMR based binding assays. In addition to monitoring fluorinated small molecules, a fluorine containing label can be incorporated in the protein of interest. Following the optimisation of a site-selective protein modification with fluorine containing tag, the protein-ligand interactions and changes in the chemical environment of the mobile loop were monitored on the example of New Delhi Metallo-β-lactamase 1 (NDM-1), which belongs to metallo-β-lacatamase family of enzymes, involved in antibiotic resistance (fig. 1C) [4].

Figure 1: Principles of assays employing fluoride based tags.

References1. A. M. Rydzik, I. K. H. Leung, G. T. Kochan, A. Thalhammer, U. Oppermann, T. D. W. Claridge and

C. J. Schofield ChemBioChem 13, 1559-63 (2012).2. A. M. Rydzik, R. Chowdhury, G. T. Kochan, S. T. Williams, M. A. McDonough, A. Kawamura and

C. J. Schofield Chem. Sci. 5, 1765 (2014).3. A. M. Rydzik, I. K. H. Leung, A. Thalhammer, G. T. Kochan, T. D. W. Claridge and C. J. Schofield

Chem. Comm. 50, 1175-1177 (2014).4. A. M. Rydzik, J. Brem, S. S. van Berkel, I. Pfeffer, A. Makena, T. D. W. Claridge and C. J. Schofield

Angew. Chem. Int. Ed. 53, 3129-33 (2014).

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O-E2-01-04

DRUGS INDUCING PHOSPHOLIPIDOSIS: CHEMICAL PROPERTIES, METABOLISM AND IN SILICO PREDICTION

L. Goracci, A. Valeri, S. Buratta, G. Ferrara, G. Cruciani

Department of Chemistry, Biology and Biotechnology, University of Perugia, 06123, Perugia, ItalyPresenting author: [email protected]

Drug-induced phospholipidosis (PLD) is a lipid storage disorder characterized by an accumulation of phospholipids and the inducing drugs in lysosomes, forming multilamellar inclusion bodies. Although PLD is often reversible and its toxicological implications is still under debate, regulatory agencies consider it at least an adverse event. Since 2004, the FDA has been investigating whether or not PLD is as a toxic effect. Nowadays, more than 50 marketed drugs are known to induce PLD [1]. Cationic amphiphilic drugs represent the main class of PLD inducers and, although the mechanism of PLD induction is still uncertain, their amphiphilic nature plays a key role in phospholipid accumulation. In the last years, a great effort has been made to predict PLD induction risk, but little is known about the chemical features typical of PLD inducers. Moreover, once drugs are metabolized, the formed metabolites can increase or decrease the PLD effect, but a few studies on the effect of metabolism have been reported [2]. In the present study, a deeper investigation on the relationship between the chemical properties of compounds and their PLD effect is reported. Methods for PLD prediction are proposed, and some general rules for the role of metabolism are discussed, based on in silico and experimental findings.

Figure 1: Scheme of the multi-technical approach used in this study (transmission electron microscopy, in vitro PLD screening, in silico methods, and MetID by LC/MSMS)

The authors gratefully acknowledge MIUR -“FIRB-Futuro in Ricerca 2010” Program (Project RBFR10X5OO) for financial support.

References1. L. A. Chatman, D. Morton, T. O. Johnson, S. D. Anway, Toxicol. Pathol. 37, 997-1005 (2009). 2. L. Goracci, M. Ceccarelli, D. Bonelli, G. Cruciani, J. Chem. Inf. Model. 53, 1436-1446 (2013).

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O-E2-01-05

MULTIDENTATE ZWITTERIONIC POLYMER MODIFIED ULTRASMALL IRON OXIDE NANOPARTICLES AS A MULTIMODAL DIAGNOSTIC

IMAGING TOOL

K. Pombo-García,a K. Zarschler,a H. Stephan,a L. Spiccia,b B.Graham.c

a Institute of Radiopharmaceutical Cancer Research, Helmholtz-Zentrum Dresden-Rossendorf, 01328, Dresden, Germany.

b School of Chemistry, Monash University, Clayton, 3800, Melbourne, Australia.c Monash Institute of Pharmaceutical Sciences, Monash University, Parkville, 3052, Australia.


The application of ultrasmall superparamagnetic iron oxide nanoparticles (USPIONs) as versatile diagnostic probes for biomedical imaging, including magnetic resonance imaging (MRI) and positron emission tomography (PET), requires hydrophilic and biocompatible surface coatings [1]. Novel coating strategies involving zwitterionic species limit nonspecific adsorption of biomolecules to the surface of nanoparticles and enable them to evade phagocytosis. This opens up promising routes for the development of clinically-approved nanoparticle-based theranostic agents with fewer off-target effects [2].We have generated a novel nanoparticle platform by introducing a zwitterionic polymer layer onto the magnetite particle surface (ZW-USPIONs). The ZW-USPIONs exhibit remarkable colloidal stabilities under extreme conditions, including high ionic strength, a wide pH range, and complex biological fluids. Furthermore, we have demonstrated that conjugation of biomolecules and/or bifunctional chelators for radiolabelling is feasible. Specifically, an epidermal growth factor (EGFR)-specific targeting vector and a 64Cu radiolabel for PET imaging have been coupled to the carboxylic groups of ZW-USPIONs [3]. In vitro evaluation of the ZW-USPIONS using an MTT assay indicate low cytotoxicity in a range of human cells for nanoparticle concentrations up to 100 µg/mL. A very low degree nanoparticle-protein complex formation upon incubation of the ZW-USPIONs with human serum has been confirmed. Engineering the surface charge and functionalization of nanoparticles using multidentate zwitterionic polymers thus provides a powerful strategy to optimise their surface properties for biological/medical applications, including as multimodal diagnostic imaging agents.

Scheme 1. (A) Non resistance to protein complex formation in a typical nanoparticle (B) Resistance to nonspecific protein adsorption of ZW-USPIONs couple to an EGFR-vector and 64Cu radiolabel.

References1. García KP, Zarschler K, Barreto JA, Hesse J, Spiccia L, Graham B, Stephan H, RSC Adv. 3,

22443 (2013).2. García KP, Zarschler K, Barbaro L, Barreto JA, O’Malley W, Spiccia L, Stephan H, Graham B,

Small. doi: 10.1002/smll.201303540 (2014).3. Viehweger K, Barbaro L, García KP, Joshi T, Geipel G, Steinbach J, Stephan H, Spiccia L,

Graham B. Bioconjugate Chem. doi: 10.1021/bc5001388 (2014).

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O-E2-02-03

AFFINITY MATRICES FOR CHEMICAL PROTEOMICS

G. Médard1, X. Ku1, F. Pachl1, P. Plattner2, B. Ruprecht1, S. Heinzlmeir1, N. Sewald2, B. Kuster1.1Chair of Proteomics and Bioanalytics, Technische Universität München, Freising, Germany

2Chair of Organic and Bioorganic Chemistry, Bielefeld University, Bielefeld, GermanyPresenting author: [email protected]

To look deeper in the proteome than by full proteome analysis of tissue or cell lysates with LC-MS/MS, enrichment methods are necessary. Some classes of proteins are particularly interesting to scrutinize, since their deregulation is closely linked with diseases. Either as a cause and they can be regarded as a potential drug target, or as a consequence and they can potentially be used as a biomarker. One of them is the kinase class. The inhibition of protein kinases has been and continue to be the object of many successful academic and industrial medicinal chemistry programmes.

The developed pharmacophores can be immobilised on solid support to constitute affinity matrices able to enrich a range of kinases. We have for instance generated efficient probes for the enrichment of AKT, VEGFR and FGFR. Our efforts of design, synthesis and systematic evaluation of existing and new ma-trices provide a convenient resource for who wants to enrich specific kinases out of a complex mixture.

To get a broader view on the differential expression of kinases between different cell lines, a matrix constituted of different unselective and complementary probes should be used. Evaluation of different combination of probes culminated in the third-generation Kinobeads. This matrix can efficiently be used in different stages of preclinical drug discovery. The observation of the differential kinase ex-pression across a panel of cell lines allows to propose new therapeutic targets. The study of kinome alterations in resistance induced cell lines helps for the identification of resistance mechanisms. The effect of drugs on cells can be monitored on the kinase level. It is of importance to emphasize that the enriched kinases are in the native state: they are full-length, folded, comprise post-translational mod-ifications, and are often complexed by a ligand. As such, they constitute a better repertoire of kinases than a panel of recombinant proteins to perform drug selectivity profilings. Hence, we have optimized this repertoire by rationally combining cell lines expressing the kinome differentially, and embarked in the systematic profiling of all available clinical kinase inhibitors by an unbiased Kinobeads competition assay.

References1. G. Médard et al. Rationally optimized chemical proteomics assay allows for practical kinase inhib-

itor profiling. submitted.2. X. Ku et al. New affinity probe targeting VEGF receptors for kinase inhibitor selectivity profiling by

chemical proteomics. Journal of proteome research 13, 2445–2452 (2014).3. X. Ku et al. A new chemical probe for quantitative proteomic profiling of fibroblast growth factor

receptor and its inhibitors. Journal of proteomics 96, 44–55 (2014).4. F. Pachl et al. Characterization of a chemical affinity probe targeting Akt kinases. Journal of pro-

teome research 12, 3792–3800 (2013).

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O-E2-02-04

Rheumatoid arthritis antibodies bind β-hairpin peptides

Sabrina Fischer and Armin Geyer

Department of Chemistry, Philipps University Marburg, Hans-Meerwein-Straße, 35032 Marburg, Germany

presenting author:[email protected]

In the early detection of rheumatoid arthritis synthetic filaggrin peptides serve as antigens for rheuma-toid specific autoantibodies (anti-citrullinated peptide antibody, ACPA) in ELISA tests [1]. In this work we present a peptide that exhibits the binding epitope of ACPA in the form of a stable folding β-hairpin [2]. The homogeneity of the peptide folding was confirmed by NMR spectroscopy and might lead to the first proposed structure of the antibody-bound conformation of the epitope. The stabilizing structural motif of model peptide 2 [3] consisting of six amino acids is integrated in the filaggrin peptide 1 by only three mutations (figure 1). The preferred binding motif of ACPA could be elucidated by determining the binding affinity of these conformationally homogeneous chimeric filaggrin peptides (3).

The investigations of folded chimeric filaggrin peptides can provide important information about the nature of the peptide–antibody binding. In addition it should be possible to filter polyclonal autoanti-bodies from mixtures of varying binding selectivities. This will assist the development of new specific ELISA test systems for a better early diagnosis of RA.

Figure 1: Concept for the synthesis of chimeric filaggrin peptides by combination of the antibody-binding epi-tope in cfc1-cyc 1 with the stabilizing properties of the cyclic β-hairpin 2. The chimeric filaggrin peptide 3 is obtained by mutation of only three amino acids in cfc1-cyc.[1] G. A. Schellekens, H. Visser, B. A. de Jong, F. H. van den Hoogen, J. M. Hazes, F. C. Breedveld, W. J. van Venrooij,

Arthritis and Rheumatism 2000, 43, 155.

[2] S. Fischer, A. Geyer, Angew. Chem. Int. Ed. 2014, 53, 3849.

[3] S. J. Russel, T. Blandl, N. J. Skelton, A. G. Cochran, J. Am. Chem. Soc. 2003, 125, 388.

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O-E2-02-05

EXPLORING HUMAN PARAINFLUENZA VIRUS TYPE-1 HEMAGGLUTININ-NEURAMINIDASE AS A TARGET FOR INHIBITOR

DISCOVERY

Ibrahim M. El Deeb, Patrice Guillon, Tanguy Eveno, Moritz Winger and Mark von Itzstein

Institute for Glycomics, Gold Coast Campus, Griffith University, Queensland, 4222, AustraliaPresenting author: [email protected]

Human parainfluenza virus type 1 is the major cause of croup in infants and young children. There is currently neither vaccine nor clinically effective treatment for parainfluenza virus infection. Haemagglutinin-Neuraminidase glycoprotein is a key protein in viral infection, and its inhibition has been a target for Neu5Ac2en-based inhibitor development. In this study we explore the effect of C-5 modifications on the potency of Neu5Ac2en derivatives that target the human parainfluenza type-1 hemagglutinin-neuraminidase protein. The effect of replacement of the C-5 acetamido group of a number of popular Neu5Ac2en-based sialidase inhibitors with the C-5 isobutyramido functionality, present in the potent hPIV-1 HN inhibitor BCX27981, was evaluated for both haemagglutinin and neuraminidase (HN) inhibitions. Significant improvement in the inhibition potency of these sialidase inhibitors was observed with installation of the C-5 isobutyramido moiety. Moreover, the inhibitor potency was also largely affected by the functionality at C-4, where both the size and charge of the substituent determines the inhibitors capacity to be well-accommodated within the C-4 binding domain. Replacement of the C-5 isobutyramido group in BCX2798 with other acylamino functionalities showed that the isobutyramido moiety is still the best C-5 substituent for maximum inhibitor potency. It has the optimum size, hydrophobic, and geometrical characters for activity. The presented structure activity relationship study emphasizes the importance of the C-5 modification in the design of any Neu5Ac2en analogue that targets hPIV-1 HN and demonstrates that the C-5 isobutyramido group is an optimal functionality for maximum inhibitor potency.

Figure 1: Molecular Dynamics Simulations of the homology model of hPIV-1 HN suggest that the C-5 binding domain within the HN can accommodate bulky alkyl moieties that enhance inhibitor potency. Panel A shows the orientation of the C-5 acetamido moiety in the active site. Panel B shows that a C-5 isobutyramido moiety is well-accommodated within the same domain.

References1. Alymova, I. V.; Taylor, G.; Takimoto, T.; Lin, T.-H.; Chand, P.; Babu, Y. S.; Li, C.; Xiong, X.;

Portner1, A. Antimicrob. Agents Chemother. 2004, 48, 1495-1502

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O-E2-02-06

Photopharmacology: From Basic Concepts to Proof of Principle, and Beyond

Wiktor Szymański, Willem A. Velema, Ben L. FeringaCenter for Systems Chemistry, Stratingh Institute for Chemistry, University of Groningen

Pharmacotherapy is severely limited by poor drug selectivity, resulting in side-effects, environmental toxicity and the emergence of resistance. Lack of selectivity is caused by the inability to control drug activity in time and space. Photopharmacology[1] (Scheme) aims at solving these issues at a molecular level by incorporating photoswitchable groups into the molecular structure of bioactive compounds.[2] This allows for the use of light as an external control element for pharmacological activity, which can be delivered with very high spatiotemporal precision.

The concept of photopharmacology has been recently used, inter alia, for the photocontrol of antibiotic activity[3] and pain perception.[4] In the first case,[3] we have designed antimicrobial agents that show no activity prior to UV-irradiation, and do not raise drug resistance in the environment. Following light-ac-tivation, they auto-inactivate on a therapeutically-relevant scale of several hours.

The presentation will describe several aspects of photopharmacology: i) basic principles behind the concept; ii) design principles for photopharmacological agents; iii) recent examples from our group and the field and iv) the main challenges for the future and the outlook on the possible applications in clinics.

1. W.A. Velema, W. Szymanski, B. L. Feringa, J. Am. Chem. Soc. 2014, 136, 2178–2191.

2. W. Szymanski, J. M. Beierle, H. A. V. Kistemaker, W. A. Velema, B. L. Feringa, Chem. Rev. 2013, 113, 6114–6178.

3. W. A. Velema, J. P. van der Berg, M. J. Hansen, W. Szymanski, A. J. M. Driessen, B. L. Feringa, Nat. Chem. 2013, 5, 924–928.

4. A. Mourot, T. Fehrentz, Y. Le Feuvre, C. M. Smith, C. Herold, D. Dalkara, F. Nagy, D. Trauner, R. H. Kramer, Nat. Methods 2012, 9, 396–402

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O-E2-03-02

MECHANISTIC AND STRUCTURAL INSIGHTS TO AN EVOLVED BENZOYLFORMATE DECARBOXYLASE WITH ENHANCED ACTIVITY

AND SPECIFICITY TOWARDS PYRUVATE

Forest H. Andrews1, Cindy Wechsler 2, Megan P. Rogers1, Danilo Meyer2, Kai Tittmann2, and Michael J. McLeish1

1Indiana University-Purdue University Indianapolis, 46202, Indianapolis, United States2 Georg-August-University Göttingen, 37077, Göttingen, Germany


Benzoylformate decarboxylase (BFDC) and pyruvate decarboxylase (PDC) are both thiamin diphosphate-dependent decarboxylases that share structural and mechanistic similarities. Both enzymes catalyze the nonoxidative decarboxylation of 2-keto acids, yet differ considerably in their substrate utilization patterns. In particular, BFDC exhibits limited activity towards pyruvate, whereas PDC has zero activity towards benzoylformate (phenylglyoxylate).

Previously, saturation mutagenesis was used to generate the BFDC T377L/A460Y variant. This variant exhibited a 10,000-fold increase in pyruvate/benzoylformate substrate utilization ratio compared to that of wt BFDC. Much of this improvement could be attributed to enhanced binding affinity for pyruvate and, concomitantly, a decrease in the kcat value for benzoylformate. However, the steady-state data did not provide any details about changes in individual catalytic steps. Given that the decarboxylation of pyruvate by PDC is known to be 40- to 150-fold slower than that of benzoylformate by BFDC, it was of interest to determine if this was a function of the substrate or the enzyme.

To gain insight into the observable changes in conversion rates of pyruvate and benzoylformate to, respectively, acetaldehyde and benzaldehyde by the BFDC T377L/A460Y variant, reaction intermediates of both substrates were analyzed by NMR and individual microscopic rate constants for elementary steps of catalysis were calculated. Additionally, the high resolution X-ray structure of the BFDC T377L/A460Y variant was determined in an attempt to understand the structural basis for the altered substrate specificity.

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O-E2-03-03

BIOENGINEERING POLYKETIDE PRECURSOR SUPPLYIN NATIVE AND HETEROLOGOUS HOSTS

A.Lechner1, B.S. Moore2, L. Katz1 and J.D. Keasling.1

1Joint BioEnergy Institute, 94608, Emeryville United States2Scripps Institution of Oceanography, University of California at San Diego, 92093, La Jolla, United

StatesPresenting author: [email protected].

The complexity of polyketides is partly due to the large pool of diverse starter units, while the extender unit variety was known to be mostly limited to the shunt products malonyl- and methylmalonyl-CoA. Over the last couple years of polyketide research new PKS extender units with various substitutions at the C2 position have been identified. They are derived from α,β-unsaturated acyl-CoA precursors via a reductive carboxylation reaction carried out by a crotonyl-CoA reductase/ carboxylase (CCR).1 We studied gene regulation of the first characterized CCR-derived extender unit, chloroethylmalonyl-CoA.2,3 This halogenated moiety highly contributes to the bioactivity of salinosporamide A, a potent proteasome inhibitor currently in clinical trials for multiple myeloma.4 The modularity of precursor biosynthesis can further be explored for engineering efforts. In one example, we isolated a pathway for the unusual extender unit isobutyrylmalonyl-CoA5 and successfully implemented its gene cassette into the heterologous FK506 pathway to biosynthesize an unnatural analog with increased bioactivity.6 The implemention of various precursor supply pathways is a prerequisite for heterologous polyketide biosynthetis in other non-PKS containing hosts, such as the the industrial producer S. cerevisiae. Current efforts are underway to evaluate and engineer S. cerevisiae as a eukaryotic polyketide production host.

1. Wilson, M. C.; Moore, B. S., Beyond ethylmalonyl-CoA: The functional role of crotonyl-CoA carboxylase/reductase homologs in expanding polyketide diversity. Nat. Prod. Rep. 2012, 29, 72-86.2. Eustáquio, A. S.; McGlinchey, R. P.; Liu, Y.; Hazzard, C.; Beer, L. L.; Florova, G.; Alhamadsheh, M. M.; Lechner, A.; Kale, A. J.; Kobayashi, Y.; Reynolds, K. A.; Moore, B. S., Biosynthesis of the salinosporamide A polyketide synthase substrate chloroethylmalonyl-CoA from S-adenosyl-L-methionine. Proc. Natl. Acad. Sci. U.S.A. 2009, 106, 12295-12300.3. Lechner, A.; Eustáquio, A. S.; Gulder, T. A. M.; Hafner, M.; Moore, B. S., Selective Overproduction of the Proteasome Inhibitor Salinosporamide A via Precursor Pathway Regulation. Chemistry & biology 2011, 18, 1527-1536.4. Macherla, V. R.; Mitchell, S. S.; Manam, R. R.; Reed, K. A.; Chao, T. H.; Nicholson, B.; Deyanat-Yazdi, G.; Mai, B.; Jensen, P. R.; Fenical, W. F.; Neuteboom, S. T.; Lam, K. S.; Palladino, M. A.; Potts, B. C., Structure-activity relationship studies of salinosporamide A (NPI-0052), a novel marine derived proteasome inhibitor. J Med Chem 2005, 48, 3684-3687.5. Wilson, M. C.; Nam, S.-J.; Gulder, T. A. M.; Kauffman, C. A.; Jensen, P. R.; Fenical, W.; Moore, B. S., Structure and biosynthesis of the marine streptomycete ansamycin ansalactam A and its distinctive branched chain polyketide extender unit. J. Am. Chem. Soc. 2011, 133, 1971-1977.6. Lechner, A.; Wilson, M. C.; Ban, Y. H.; Hwang, J.-y.; Yoon, Y. J.; Moore, B. S., Designed Biosynthesis of 36-Methyl-FK506 by Polyketide Precursor Pathway Engineering. ACS Synthetic Biology 2012.

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O-E2-03-04

Luminescent Silver Nanoclusters for Biological Imaging

A. Bunschoten1, P.T.K. Chin1, M. van der Linden,2 A. Meijerink,2 F.W.B. van Leeuwen1,3.1Department of Radiology, Interventional Molecular Imaging Laboratory, Leiden University Medical

Center, Leiden, the Netherlands. 2Utrecht University, Condensed Matter and Interfaces, Debye Institute for Nanomaterials Science,

Utrecht, The Netherlands. 3Department of Bionanotechnology, Wagening University, Wageningen, the Netherlands.


Inorganic nanoparticles have favorable optical characteristics, making them an alternative to organic dyes. However, these luminescent inorganic nanoparticles are often synthesized from toxic metal ions (e.g. Cd) and are relatively large (> 10 nm), which limits their value for biomedical imaging. In search of more inert and smaller luminescent nanoparticles we focused our efforts on silver nanoclusters. The reduction of silver nitrate in the presence of dihydrolipoic acid (DHLA) results in the formation of water soluble silver nanoclusters that have favorable optical properties (λex = 500 nm; λem

= 650-700 nm).[1] Electron microscopy revealed that these particles have a diameter of around 1.5 nm. Electron spray mass spectrometry indicated that these nanoclusters consist of 25 silver atoms surrounded by 12 DHLA ligands. To optimize the optical properties further the influence of surface ligands was evalu-ated. Initially we used an increase in polarity to improve the quantum yield; the introduction of PEG ligands with various end-groups improved the luminescence 9-fold.[2] Second, we tried to achieve the same effect using the biocompatible protein human serum albumin (HSA); HSA is the most abundant protein in the human circulation and is specialized in binding and coordinating a large variety of com-pounds. In this study we evaluated the encapsulation of silver nanoclusters by HSA. This yielded a 1:1 (HSA:silver-nanocluster) ratio that yielded a 9-fold increase in luminescence and a 2-fold increase in luminescence lifetime. The HSA-encapsulation also protected the silver core from a loss of lumines-cence upon heavy metal poisoning.Previously we have applied HSA for the formation of (targeted) imaging tracers,[3-5] meaning that next to protecting the silver core, HSA can provide a platform for functionalization. By covalently attaching peptide moieties that target the chemokine receptor 4 (CXCR4) we were able to modify the HSA-silver nanoclusters into biocompatible targeted imaging probes for the CXCR4-receptor. A prop-erty that was verified in vitro using fluorescence confocal microscopy.References

1. B. Adhikari, Chem. Mater. 22: 4364-71 (2010).2. P.T.K. Chin, Nanotechn.24(7): 075703 (2013).3. A. Bunschoten, Biomaterials 33(3): 867-75 (2012).4. A.C. van Leeuwen, J. Biomed. Opt. 16(1): 016004 (2011).5. H.G. van der Poel, Eur. Urol. 60: 826-33 (2011).

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O-E2-03-05

Hit-to-lead optimisation of a compound series with trypanosomacidal activity

Lori Ferrins1, Raphael Rahmani1, Stephanie Russell2, Amy Jones3, Nghi Nguyen1, Marcel Kaiser4, Susan Charman5, Vicky Avery3, Matthew Piggott2, Jonathan Baell1

1Monash Institute of Pharmaceutical Sciences, Parkville, Australia2The University of Western Australia, Crawley, Australia

3Eskitis Institute for Drug Discovery, Griffith University, Nathan, Australia4Swiss Tropical and Public Health Institute, Soccinstrasse, Switzerland

5Centre for Drug Candidate Optimisation, Parkville, Australia

American trypanosomaisis, or Chagas disease, and human African trypanosomiasis (HAT), more com-monly known as sleeping sickness, are caused by the protozoan Trypanosoma cruzi and Trypanosoma brucei respectively. Already nifurtimox is on the market and able to treat both of these diseases, how-ever, further treatments are urgently required.Chagas disease is a potentially life-threatening illness and is reported to affect between 7 and 8 million people in Latin America. Depending on the form of the disease some patients will never know that they are infected, while others will experience heart and digestive issues.HAT on the other hand has been declared a neglected tropical disease by the World Health Organiza-tion, affecting approximately 20,000 people in the remotest parts of Africa. This disease affects the central nervous system, resulting in disrupted sleep patterns, brain damage and eventual death. Current treatments for this disease often result in the development of long term health issues and can lead to death in up to 5% of patients.A whole organism high-throughput screen of approximately 87,000 compounds from the WEHI/Bio21 screening library was conducted against T. brucei and led to the identification of a number of new compound series as inhibitors of T. brucei. These have been progressed through to medicinal chemistry optimisation and the current SAR will be discussed around one of these series which has also shown potent activity against T. cruzi.

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O-E2-03-06

Surface stress sensors for rapid and ultrasensitive detection of active free drugs in human serum

Joseph W. Ndieyira1,2, Natascha Kappeler1, Stephen Logan1, Matthew A. Cooper3, Chris Abell4, Rachel A. McKendry1 and Gabriel Aeppli1

1London Centre for Nanotechnology, Division of Medicine and Department of Physics and Astronomy, University College London, United Kingdom

2Jomo Kenyatta University of Agriculture and Technology, Department of Chemistry, Kenya3Institute for Molecular Bioscience, University of Queensland, Brisbane, 4072, Australia

4Department of Chemistry, Lensfield Road, University of Cambridge, Cambridge CB2 1EW, United Kingdom

Presenter’s e-mail address: [email protected]

There is growing appreciation that mechanical signals can be as important as chemical and electrical signals in biology. To include such signals in a systems biology description for understanding pathobiology and developing therapies, quantitative experiments on how solution phase and surface chemistry together produce biologically relevant mechanical signals are needed [1]. Due to the appearance of drug-resistance hospital “superbugs”, a system of large current interest is the destruction of bacteria by antibiotics forming bound drug/target complexes which stresses bacterial cell membranes [2]. Here we use nanomechanical cantilevers as surface stress sensors together with equilibrium theory to describe quantitatively the mechanical response of a surface receptor to different antibiotics in the presence of competing soluble ligands (Fig. 1). The antibiotics examined are the standard, FDA

approved drug of last resort, vancomycin and yet-to-be approved oritavancin. The work reveals variations among strong and weak competing ligands, such as proteins in human serum, which determine dosages in drug therapies [3]. These findings further enhance our understanding of the biophysical mode of action of antibiotics and will help develop better treatments, including choice of drugs as well as dosages, against pathogens.

Fig. 1 - Exploiting the nanomechanics of drug-target interactions to investigate the impact of dosing and competing ligands on the functionality of drug molecules where the schematics represent solution and surface interactions. Here the molecules can bind to the surface

tethered receptors to form a bound complex. The efficacy is measured for a model bacteria cell wall analogue tethered to one side of a cantilever surface.REFERENCES[1] Ndieyira, J. W. et al. Nature Nanotech. 3, 691 (2008).[2] Dwyer, D. J. et al. Molecular Cell 46, 561 (2012).[3] Ndieyira, J. W. et al. Nature Nanotech. 3, 691 (2008).

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O-E2-03-07

CHEMICAL BIOLOGY OF PROLYL DI-HYDROXYLASES – FROM RING OPENING TO READTHROUGH

C. Loenarz1, R. Sekirnik1, A. Thalhammer1, A. Wolf1, C. J. Schofield.1

1Department of Chemistry, University of Oxford, OX1 3TA Oxford, United KingdomPresenting author: [email protected]

In the pursuit of chemically interesting molecular questions of biological relevance, we have recently identified several unprecedented post-translational modifications, including 3-hydroxyhistidine, 3-hydroxyarginine and 3,4-dihydroxyproline, to components of the protein synthesis machinery [1-4]. The enzymes responsible for these modifications are members of the 2-oxoglutarate oxygenase superfamily [5-6]. Identified phenotypical effects from the deletion of these enzymes include growth defects [3], decreases in global translation rate [2,4], decreased resistance to antibiotics and altered ribosomal accuracy [1].

I identified the unusual amino acid dihydroxyproline in S. cerevisiae RPS23 at the ribosomal protein-residue in closest proximity to the mRNA-tRNA decoding centre (Fig. 1). Consistent with this location, RPS23 hydroxylation affects translational accuracy. Ribosomes lacking RPS23 hydroxylation manifest up to 10-fold increased readthrough of premature stop codons, in an mRNA sequence dependent manner [1].

This finding suggests novel approaches for the treatment of genetic diseases linked to nonsense mutations, and is of commercial value: >1,800 separate human medical disorders are thought to be due to premature termination, including cystic fibrosis, muscular dystrophy and beta-thalassaemia. In addition, many sporadic colorectal cancers feature premature stop codon mutations. The

development of novel small molecules that promote stop codon readthrough is therefore of considerable interest. I will also report ongoing studies, investigating whether manipulation of RPS23 hydroxylation, e.g. by small-molecule inhibition, could help patients suffering from genetic disorders due to nonsense mutations.

References1. C. Loenarz et al., Proc. Natl. Acad. Sci. U.S.A. 111, 4019 (2014).2. W. Ge et al., Nat. Chem. Biol. 8, 960 (2012).3. M. J. Katz et al., Proc. Natl. Acad. Sci. U.S.A. 111, 4025 (2014).4. R. S. Singleton et al., Proc. Natl. Acad. Sci. U.S.A. 111, 4031 (2014).5. C. Loenarz and C. J. Schofield, Nat. Chem. Biol. 4, 152 (2008).6. C. Loenarz and C. J. Schofield, Trends Biochem. Sci. 36, 7 (2011).

Figure 1: The ribosomal protein RPS23 is prolyl mono- and di-hydroxylated in humans and yeast, respectively. Lack of RPS23 hydroxylation leads to increased readthrough of premature stop codons, allowing synthesis of the full-length protein.

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O-E2-04-01

BUILDING DEFINED PROTEIN-DRUG CONJUGATES FOR TARGETED CANCER THERAPY

G. J. L. Bernardes.1,2

1Department of Chemistry, University of Cambridge, Lensfield Road, Cambridge CB2 1EW, United kingdom

2Instituto de Medicina Molecular, Faculdade de Medicina da Universidade de Lisboa, Av. Prof. Egas Moniz, 1649-028 Lisboa, Portugal


The targeted delivery of effector molecules into diseased tissues has emerged as a promising strategy for the treatment of cancer and other serious conditions. Linking a therapeutic effector (e.g. cytotox-ics, proinflammatory cytokines or radionuclides) to a ligand specific to a marker of disease results in preferential accumulation of the effector molecule at the target tissue. This offers the double benefit of increased effective concentrations at the intended site of action and low concentrations in healthy tis-sues, thus reducing side effects. Our work explores the interplay between effector molecules, targeting ligands and site-selective protein conjugation chemistry to create safer, more selective and efficient cancer therapeutics.This lecture will cover recent examples of emerging areas in our group in (i) targeted drug conjugates construction with an emphasis on traceless antibody-drug conjugates and (ii) use of carbon monoxide (CO) as a immunomodulator signalling molecule for applications in cancer therapeutics.(i) A new non-internalizing antibody-drug conjugate (ADCs) that cures cancer in immunocompetent mice bearing tumours will be presented.[1,2] This ADC was built using of a robust site-selective di-sulfide conjugation protocol.[3] Using this protocol we were able to systematically investigate how the therapeutic efficacy of a traceless, vascular targeting ADC is affected by the length of a spacer in-troduced between the antibody’s globular fold and the site of drug attachment.[4] (together with Prof. Dario Neri)(ii) We are exploring the immunomodulatory effects of CO for cancer therapeuty.[5] A new CORM conjugate is able to ablate the expression of the pro-inflammatory cytokines TNF-α and IL-6 , and of the chemokine, IL-8, which are involved in tumour progression and metastasis. In an immunocompe-tent mouse model of colon carcinoma that is not cured by the standard-care-of therapy 5-fluorouracil (5-FU), the new CORM conjugate can elicit a strong-anti-tumour activity.[Unpublished results]

References1. G.J.L. Bernardes, G. Casi, S. Trüssel, I. Hartmann, K, Schwager, J. Scheuermann, and D. Neri, An-gew. Chem. Int. Ed. 51, 941-944 (2012).2. E. Perrino, M. Steiner, N. Krall, G.J.L. Bernardes, F. Pretto, G. Casi, and D. Neri,Cancer Res. doi:10.1158/0008-5472.CAN-13-2990 (2014).3. G.J.L.Bernardes, M. Steiner, I. Hartmann, D. Neri, and G. Casi, Nature Protocols, 8, 2079-2089 (2013).4. M. Steiner, I. Hartmann, E. Perrino, G. Casi, S. Brighton, I. Jelesarov, G.J.L. Bernardes*, and D. Neri, Chemical Science, 4, 297-302 (2013).5. S. García-Gallego, G.J.L. Bernardes*, Angew. Chem. Int. Ed. doi:10.1002/anie.201311225 (2014).

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O-E2-04-02

Nanocarrier and Cargo Fate on a Cellular Level: Kiss-and-run and Intracellular Release of Drugs and Molecules from Nanocarriers

Daniel Hofmann1,2, Stephanie Tomcin1, Annette Kelsch3, Rudolf Zentel3, Katharina Landfester1, Volker Mailänder1,2*

1 Max Planck Institute for Polymer Research, Ackermannweg 10, 55128 Mainz, Germany2 III. Medical Clinic, Hematology, Oncology and Pneumology, University Medical Center of the

Johannes-Gutenberg University Mainz, Langenbeckstr. 1, 55101 Mainz, Germany3Institute of Organic Chemistry, Johannes Gutenberg-University Mainz, Duesbergweg 10-14, 55128

Mainz, GermanyPresenting author: [email protected]

Large efforts have been made to understand the interactions between cells and nanoparticle drug delivery devices. These efforts have often been focused on uptake of nanoparticles and their intracellular trafficking pathways[1]. Indeed, nearly all concepts of nanocarriers as drug delivery devices rely on intracellular uptake. We demonstrate an alternative concept for rapid and specific delivery of cargo by nanoparticles to TIP47+/ADRP+ lipid droplets[2]. Here a very hydrophobic dye (perylenemonoimide) is used as a dye in poly-L-lactide or polystyrene particles to demonstrate this type of delivery mechanism. The delivery mechanism is extremely fast (within several minutes) and here no uptake is required. Uptake of nanoparticles is then followed after a longer period of time and increases even after hours. The model can serve as a novel strategy for the non-invasive delivery of drugs by releasing hydrophobic cargo, in our case a model dye, through a kiss-and-run mechanism between nanoparticle and cell membrane. While in this first system the delivery occurs at the first contact of the nanocarrier with cells we demonstrate in a second set of experiments that the release of other cargoes can occur after the uptake. Here nanocarriers with poly-L-lactide or polystyrene cores have been synthesized with fluorescent blockcopolymers as surfactants[3]. We demonstrate that the nanocarrier with the blockcopolymer is first

internalized while then after hours the blockcopolymer ends up in other intracellular compartments than the polymeric core. This offers further possibilities to deliver specific components to intracellular sites in a controlled manner.

Figure 1: Schematic illustration of the kiss-and-run mechanism. Nanoparticles briefly interact with the lipid bilayer of a cell (A) or a giant unilamellar vesicle (B), thereby releasing its dye that accumulates in lipid droplets (LD) or in the membrane, respectively.

References1. Hofmann, D. and V. Mailander, Nanomedicine, 8(3): p. 321-323 (2013)2. Hofmann, D., et al., Chem Commun (Camb), 50(11): p. 1369-71 (2014)3. Kelsch, A., et al., Biomacromolecules, 13(12): p. 4179-4187 (2012)

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O-E2-04-03

New Cu(II)-Sn(IV) heterobimetallic complexes as cancer chemotherapeutic agents: DNA binding/cleavage studies

Ahmad Asim1, Sartaj Tabassum1.1Department of Chemistry, Aligarh Muslim University, 202002, Aligarh, India.


Transition metal ions can twist the general properties of the free organic moiety after complexation. These complexes can be used in diverse fields as enzyme mimic, therapeutic agents and catalysts. Metal –based compounds are more appealing for design of new chemotherapeutic drugs as metal plays an important role in delivery of drugs away from the sites where they exert most toxicity and toward their sites of action. Most of the drugs exert cytotoxic as well as therapeutic effect either by direct interaction with DNA or by inhibition of Topoisomerase. DNA binding by small ligands or metal complexes is important for development of drugs targeted to DNA. Medicinal inorganic chemistry, a new subarea of bioinorganic chemistry has gained momentum after the serendipitous discovery of anticancer properties of inorganic compound, cis-[PtCl2(NH3)2], cisplatin. Cisplatin though, world’s best selling antitumor drug currently in use to treat solid malignancies., nevertheless, there were certain issues such as, systemic toxicity, intrinsic resistance and narrow spectrum of cytotoxicity which limits their use. Therefore, new modulates in chemotherapy led to the discovery of other platinum and non-platinum drugs which could be exploited as antitumor agents.

Figure : Multifunctional approach of Cu(II)-Sn(IV) heterobimetallic complexesPresent investigation focuses on the recent strategy of molecular drug design, to find chemotherapeutic compounds with low toxicity. New heterobimetallic complexes possessing (CuII/SnIV and ZnII/SnIV) bimetallic cores were synthesized from their monometallic Cu(II) 1 and Zn(II) 2 complexes by de novo design strategy involving a chiral biologically active ligand scaffold. The Complexes were characterized by elemental analysis, polarimetry, IR, CD, UV and multinuclear (1H, 13C, 119Sn) NMR spectral data. The interaction of complexes with calf thymus DNA was studied by employing various biophysical techniques (viscometry, absorption, emission and circular dichoric spectral methods) which reveals their avid DNA binding via electrostatic (external groove) or by partial intercalation mode. The results showed significantly higher binding affinity of heterobimetallic complexes as compared to monometallic complexes.

Reference[1] Sartaj Tabassum, Waddhaah M. Al-Asbahy, Mohd. Afzal, Farukh Arjmand, and Vivek Bagchi, Dalton Trans, 41, 4955, (2012).[2] Sartaj Tabassum, Ahmad Asim, Rais Ahmad Khan, Zahid Hussain, Saurabh Srivastav, Saripella Srikrishna, and Farukh Arjmand, Dalton Trans, 42, 16749, (2013).

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O-E2-04-04

Substrate-Initiated Cell-Penetrating Poly(disulfide)s: Novel Vectors for Cellular Uptake

G. Gasparini1, E.-K. Bang1, G. Molinard1, D. V. Tulumello2, S. Ward1, S. O. Kelley2, A. Roux1, N. Sakai1, S. Matile1.

1School of Chemistry and Biochemistry, National Centre of Competence in Research (NCCR) Chemical Biology, University of Geneva, 1211, Geneva, Switzerland

2Department of Pharmaceutical Sciences, University of Toronto, M5S 3M2, Toronto, CanadaPresenting author: [email protected]

An emerging new class of molecular transporters is represented by cell-penetrating poly(disulfides)s (CPDs) [1]. They are polymers held together by disulfide bonds that, after uptake, undergo reduction to yield the constituting monomers, due to the presence of endogenous glutathione. This drastically decreases their toxicity and broadens the spectrum of application. Inspired by surface-initiated ring-opening disulfide-exchange polymerization [2], we developed a new method to generate CPDs directly on a substrate of free choice [3]. This approach allows us to covalently link the substrate (formally, any molecule in need of assistance to enter cells) to the CPDs forthwith during their synthesis, releasing it only when the cellular uptake takes place. It not only simplifies the synthetic efforts to generate CDPs, but it also broadens the type of substrate that could be delivered, avoiding tedious and complex noncovalent formulations typical of the “classic” way to employ CPDs, in favor of covalent delivery of unmodified substrates.

S S S S

S IO

m

Initiator Propagators Terminator

n

Molecule of

free choice Post-polymerizationfunctionalization

Intracellulardepolymerization

Externalpolymerization

Thiol-mediatedCellular Uptake

Figure 1: Substrate-initiated CPDs concept and its application on cellular uptake on HeLa cells.

We recently applied our method to grow polymers on two different fluorescent probes and we used the resulting CPDs for cellular uptake into HeLa cells (Fig. 1). Moreover, we investigated the effects of different functional groups present on the surface of the polymers on intracellular localization (cytosol, nucleoli, endosomes) [4]. Finally, special attention was dedicated to verify the hypothesis of thiol-mediated cellular uptake [5], both in vitro and in vivo, in order to rationalize the excellent performances of this new class of transporters.

References1. E.-K. Bang, M. Lista, G. Sforazzini, N. Sakai and S. Matile, Chem. Sci. 3, 1752-1763 (2012).2. a) N. Sakai, M. Lista, O. Kel, S. Sakurai, D. Emery, J. Mareda, E. Vauthey and S. Matile, J. Am.

Chem. Soc. 133, 15224-15227 (2011). b) M. Lista, J. Areephong, N. Sakai and S. Matile, J. Am. Chem. Soc. 133, 15228-15230 (2011).3. E.-K. Bang, G. Gasparini, G. Molinard, A. Roux, N. Sakai and S. Matile, J. Am. Chem. Soc. 135,

2088-2091 (2013).4. G. Gasparini, E.-K. Bang, G. Molinard, D. V. Tulumello, S. Ward, S. O. Kelley, A. Roux, N. Sakai

and S. Matile, J. Am. Chem. Soc. DOI:10.1021/ja501581b (2014).5. A. G. Torres and M. J. Gait, Trends Biotechnol. 30, 185-190 (2012).

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O-E2-04-05

Targeted delivery of Aptamers to cancer cells

Fadwa Odeh1, Said Ismail2, Rana Abu Dahab3, Hanan Azzam4, Bashaer Abu Rmeileh1, Abeer Al Bawab4

1Department Of Chemistry, School Of Science, The University Of Jordan2Department Of Biochemistry, School Of Medicine, The University Of Jordan

3Department Of Pharmaceutical Sciences, School Of Pharmacy, University Of Jordan4Hamdi Mango Center For Scientific Research, The University Of Jordan

Aptamers, which are single stranded DNA, are designed using SELEX to be specifically bond to special markers on targeted cancer cells. in order to check their specificity, effectivity and stability, these designed Aptamers were synthesized to be tested on targeted cancer cell lines. however, since Aptamers are very large molecules and can not go through cell barriers, these Aptamers were loaded in nanoparticles. the effectiveness of these loaded nanoparticles were tested against several cell lines.

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O-E3-01-01

BACTERIAL SUPERGLUE ENABLING SUPRA-MOLECULAR SYNTHESIS OF PROTEIN TENTACLES AND DENDRIMERS

G. Veggiani1, J. Fierer1, C. Schoene1, M. Howarth.1

1University of Oxford, Department of Biochemistry, South Parks Road, OX1 3QU, Oxford, UKPresenting author: [email protected]

Interactions between biomacromolecules are nearly always reversible, limiting possibilities for robust supra-molecular assembly and for resisting force or harsh conditions. We have created tools enabling irreversible interaction, based on a special feature of the chemistry of the pathogenic bacterium Streptococcus pyogenes. Through rational engineering of a protein from this bacterium involved with invading human cells, we generated a peptide (SpyTag) bearing a carboxylic acid side-chain which spontaneously reacts with an amine side-chain, to form an amide bond to the protein partner (SpyCatcher). Reaction is quick, high-yielding, genetically-encoded and has specificity in bacterial and human cells. We have also created a three-way split protein (SpyLigase) that can direct covalent ligation between two peptide tags. Applications of these protein padlocks will be described, including multiply branching assemblies for activating cell signalling, making enzymes resilient to boiling, and generating protein tentacles for maximising rare cell capture from blood.

References1. C. Schoene, J. O. Fierer, S. P. Bennett, M. Howarth, Ang. Chem. in press (2014).2. J. O. Fierer, G. Veggiani, M. Howarth, Proc. Natl. Acad. Sci. U S A. 111, E1176-81 (2014). 3. M. Fairhead, D. Krndija, E. D. Lowe, M. Howarth, J. Mol. Biol. 426, 199-214 (2014).4. B. Zakeri, J. O. Fierer, E. Celik, E. C. Chittock, U. Schwarz-Linek, V. T. Moy, M. Howarth, Proc. Natl. Acad. Sci. U S A. 109, E690-7 (2012).

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O-E3-01-02

SYNTHESIS OF DI- AND TRISACCHARIDE FRAGMENTS OF THE IN-NER CORE OF ACINETOBACTER LIPOPOLYSACCHARIDE AS LECTIN

LIGANDS

B. Pokorny1, S. Müller-Loennies2, P. Kosma1

1 Department of Chemistry, University of Natural Resources and Life Sciences, Muthgasse 18, 1190 Vienna, Austria

2Research Center Borstel, Parkallee 1-40, 23845 Borstel, GermanyPresenting author: [email protected]

Increasing antibiotic resistance of human pathogens urges to develop new therapeutic strategies. In the Gram-negative bacterial cell wall lipopolysaccharide (LPS) constitutes the outer sphere of the outer membrane and is frequently recognized by sugar-binding proteins (lectins) triggering immune response in hosts. Identification of the relevant bacterial epitopes is fundamental for e.g. vaccine development. Interestingly, an atypically strong interaction of isolated rough-type LPS with the murine and human mannose-binding lectin (MBL-A) has been identified in Acinetobacter haemolyticus [1] – a pathogen which causes severe nosocomial infections. While the structure of its LPS has already been elucidated [2], the epitope binding to the lectin remains unclear.

OHO

HOO

OHO

OMe

O

CO2-Na+

OR

OHOHOHO

HO

HO

OH

R'

Smith

degradation

R =

H, P(O)(OH)2

R' =

H

KdoR'

= OH

Ko

Figure 1: Natural and modified inner core fragments of Acinetobacter LPS

The high-yielding and stereoselective preparation of an orthogonally protected α-d-Glc-(1→5)-Kdo (3-deoxy-α-d-manno-oct-2-ulosonic acid) disaccharide – constituting the key unit for further modifi-cations (phosphorylation, Smith degradation) and glycosylations – will be presented [3] (Fig.1). Addi-tionally, disaccharides containing the 3-hydroxylated pendant d-glycero-α-d-talo-oct-2-ulosonic acid (Ko), that is observed in a few serotypes, have been synthesized. Preliminary results from ELISA bind-ing studies will illustrate a structure-affinity relationship.

Financial support from the Austrian Science Fund (FWF) is gratefully acknowledged (P24921-N28)References1. L. Brade, et al., Infect. Immun. 50, 687 – 694 (1985)2. E. V. Vinogradov, et al., Eur. J. Biochem. 247, 82 – 90 (1997)3. B. Pokorny, et al., Carb. Res. 391, 66 – 81 (2014).

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O-E3-01-03

A theoretical study on the reaction pathway leading to the formation of 2-aceto-2-hydroxybutyrate in the catalytic cycle of AHAS

Leslie Sánchez1, Gonzalo A. Jaña2, Eduardo J. Delgado1

1 Faculty of Chemical Sciences, Universidad de Concepción, Concepción, Chile.2 Departamento de Ciencias Químicas, Universidad Andrés Bello, Concepción, Chile

[email protected]

The reaction between the intermediate 2-hydroxyethyl-thiamin diphosphate (HEThDP-) and 2-ketobutyrate, in the third step of the catalytic cycle of acetodydroxy acid synthase (AHAS), is addressed from a theoretical point of view by means of hybrid quantum/molecular mechanical (QM/MM) calculations. The QM region includes one molecule of 2-ketobutyrate, the HEThDP- intermediate, and the residues Arg 380 y Glu 139; while the MM region includes the rest of the protein. The study includes potential energy surface (PES) scans, Figure 1, in order to identify and characterize critical points on it, transition state search and activation barrier calculations. The results show that the reaction occurs via a two-step mechanism corresponding to the carboligation and proton transfer in the first stage; and the product release in the second step. The corresponding observed activation barriers are 11 and 15 (kcal/mol), respectively, indicating that the second step is the rate controlling stage, in agreement with the empirical evidence [1].

Figure 1: 3D-view of the potential energy surface (PES).

References1. L. Sánchez, G.A.Jaña, E.J. Delgado, J. Comput. Chem. 35, 488-494 (2014).

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O-E3-01-04

The synthesis of novel, peptidic kinase inhibitors with cytostatic/cytotoxic activity

R. Ostaszewski, W. Szymanski, S., Klossowski1Institute of Organic Chemistry PAS, Kasprzaka 44/52, 01-224 Warsaw, Poland

The promising use of small peptides as therapeutics suffers seriously from the problems with pharmacokinetics of these compounds. These problems include proteolytic instability and high polarity, which prevents small peptides from crossing cell membranes. The synthesis of peptidomimetics aims at the solution of these problems. A novel method for the preparation of peptidomimetics of structure presented on Figure 1 has been recently developed in our group. [1]. It uses Passerini multicomponent reaction for the preparation of racemic scaffolds.

Figure 1: Synthesis of small peptides vis Passerini reaction

The utility of a novel, chemoenzymatic procedure for the stereocontrolled synthesis of small peptides will be presented in the preparation and structure optimisation of dipeptides with cytostatic/cytotoxic activity. The method uses Passerini multicomponent reaction for the preparation of racemic scaffold which is then enantioselectively hydrolysed by hydrolytic enzymes. Products of these transformations are further functionalised towards the kinases inhibitors. [2]

This work was supported by project ”Biotransformations for pharmaceutical and cosmetics industry” No. POIG.01.03.01-00-158/09-01 part-financed by the European Union within the European Regional Development Fund.

References[1]W. Szymanski, M. Zwolinska, R. Ostaszewski Tetrahedron, 2007, 63, p. 7647[2]W. Szymanski, M. Zwolinska, S. Klossowski, I. Mlynarczuk-Bialy, L. Bialy, T. Issat, J. Tadeusz; J. Malejczyk, R.

Ostaszewski Bioorg. Med. Chem. 2014, 22(5), p. 1773-1781

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O-E3-01-05

ORGANIC FLUORESCENT NANO-OBJECTS FOR BIOIMAGING APPLICATIONS ON E.COLI BACTERIA

Yang Si1, Rachel Méallet-Renault1, Gilles Clavier1, Bianca Sclavi2

1PPSM, CNRS UMR 8531, ENS-Cachan, Cachan, 94235, France2LBPA, CNRS UMR 8113, ENS-Cachan, Cachan, 94235, France

E-mail : [email protected]

Bacteria are the most abundant organisms in the world. The study of bacterial internal and external biological processes is very important to understand how bacteria adapt to different growth environments and in response to stimuli.

Optical labeling is one of the most common methodologies used for bio-analytical purposes. The fundamental issues for any fluorescent material are the same: brightness and stability. In the quest for very bright and stable labels, novel polymer-based, self-stabilized, fluorescent nanoparticles (FNPs) and fluorescent polymer chains (FPCs) have been developed in the PPSM laboratory. They are brighter, more stable, they photobleach slowly and are more easily functionalized compared with other fluorescent labels like GFP and QDs [1].

A methodology to insert these FNPs (60nm) into E.coli bacteria was developed. To control if the FNPs are indeed internalized, we developed a protocol based upon FNPs luminescence quenching by methylene blue.

Biotin conjugated FNPs could be used to study specific membrane proteins. By using a streptavidin-biotin link, we made a “Sandwich” to build a bridge between particles, specific antibodies and bacteria. SPR, fluorescence images and SEM images will demonstrate the interaction of biotin conjugated FNPs with E.coli bacteria.

More recently we demonstrated that pH sensitive FNPs can be used to measure the presence of E.coli growth. Incubating growing E.coli bacteria with pH sensitive FNPs will cause the fluorescence intensity of FNPs to decrease. Therefore pH sensitive FNPs can be used to detect the presence of E.coli. These FNPs are more sensitive than traditional pH molecular sensors or typical OD measurements.

Negatively charged Fluorescent Polymer Chains (5nm) can easily enter into E.coli bacteria. It is found that FPCs can label the cytoplasm but not the DNA, which appears to be more compact. These unique properties will allow the study of DNA and cytoplasm viscosity changes during bacterial growth.

[1] Grazon, C., J. Rieger, et al. Macromolecular Rapid Communications.2011, 32(9-10): 699-705.

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O-E3-01-06

Tracking Structure, Dynamics and Reactivity of Biological Systems by Ultrafast Two-Dimensional Electronic Spectroscopy

Ivan Rivalta 2, Artur Nenov2, Oliver Weingart3, Giulio Cerullo4, Shaul Mukamel3, Marco Garavelli1,5

1Laboratoire de Chimie, École Normale Supérieure de Lyon, 46, allée d’Italie 69364 Lyon, France. 2Dipartimento di Chimica “G. Ciamician”, Università di Bologna, V. F. Selmi 2, 40126 Bologna,

Italy. 3Institut für Theoretische Chemie und Computerchemie, Heinrich-Heine-Universität Düsseldorf, Uni-

versitätsstr. 1, 40225 Düsseldorf, Germany. 4IFN-CNR, Dipartimento di Fisica, Politecnico di Milano, Piazza L. da Vinci 32, 20133 Milano, Italy.

5Department of Chemistry, University of California, Irvine, California 92697-2025, United States

Two-dimensional electronic spectroscopy (2DES) based on ultrashort laser pulses is a cutting-edge technique to track electronic transitions in complex systems with unprecedented spectral and time reso-lution. 2DES can be used to investigate energy transfer, structure, conformation dynamics and chemical reactivity in a wide range of systems in physical chemistry, energy sciences and biophysics. By spread-ing the information content of the nonlinear signal on two frequency axes, 2DES provides a wealth of novel information on molecular structure and dynamics with respect to the linear signal collected in traditional 1D experiments. However, the interpretation of 2D electronic spectra is challenging and computational modeling is required to disentangle the information contained in the nonlinear optical response of the sample. In this talk a computational tool that can be routinely applied to accurately simulate 2DES spectra of multichromophoric systems is introduced. Multiconfigurational and multi-reference perturbative methods have been used to reliably calculate the electronic properties of multi-chromophoric systems within a hybrid Quantum Mechanics/Molecular Mechanics (QM/MM) scheme in conjunction with molecular dynamics (MD) techniques to assess environmental and conformational effects that shape the 2D electronic spectra. Applications of this methodology for the study of structure and folding dynamics of proteic systems in solution and photochemistry of retinal chromophores are showed, demonstrating that 2DES holds the promise to become a novel diagnostic tool complementary to well-established multidimensional NMR and 2DIR techniques.

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O-E3-01-07

In Silico Study of Novel Active Linezolid-like 1,2,4-Oxadiazole Derivatives.

Cosimo G. Fortunaa, Rosario Musumecib, Andrea Pacec, aDipartimento di Scienze Chimiche, Università di Catania, Viale A. Doria,6 95125 Catania, Italy.

bDipartimento di Medicina Clinica e Prevenzione, Università di Milano-Bicocca - Edificio U8 - Via Cadore 48, 20052 Monza (MB), Italy.

c Dipartimento di Scienze e Tecnologie Molecolari e Biomolecolari (STEMBIO), Sez. Chimica Organica “E. Paternò”, Università degli Studi di Palermo, Viale delle Scienze Ed. 17 – Parco

D’Orleans II, I-90128, Palermo, Italy.

Antibiotics have revolutionized the medical treatment of bacterial infections. Widespread use and misuse of antibiotics, however, has led to an increasing level of antibiotic resistance among common disease-causing bacteria. In particular, twenty years ago the World Health Organization (WHO) reported that more than 95% of S. aureus worldwide was resistant to penicillin, and 60% to its derivative methicillin1. Since 2000 Linezolid, a new 1,3-oxazolidinone antibiotic, has been considered the “drug of last resort”, being active against most Gram-positive bacteria that cause disease, including streptococci, vancomycin-resistant enterococci (VRE), and methicillin-resistant Staphylococcus aureus (MRSA). Despite to the novel scaffold and mechanism of action, bacterial resistance to linezolid has been already detected.2 In this context many researchers have been trying to modify the structure of linezolid to perform a structure activity relationship (SAR) study and to possibly improve the antibacterial activity before linezolid-resistance is emerging.We recently synthesized linezolid analogues,3,4 and some of them showed activity values comparable to linezolid. An in silico study is proposed to have a better understanding of the key interactions with the biological target for activity. A comparison of the possible binding modes for the tested compounds using two complementary approaches (ligand-based and structure-based) is discussed. In particular, the new 1,2,4-oxadiazole moiety seems to perfectly mimic the linezolid morpholinic ring interacting with the U2585 residue of the 50S ribosomal subunit.

1 Neu H.C. Science, 1992, 257, 1064-10732 Kelly S.; Collins J.; Maguire M.; Gowing C.; Flanagan M.; Donnelly M.; Murphy P. G. J. Antimicrob. Chemother. 2008, 61, 901-907.3 Palumbo Piccionello A.; Musumeci R.; Cocuzza C.; Fortuna C.G.; Guarcello A.; Pierro P.; Pace A. Eur. J. Med. Chem., 2012, 50, 441-448. 4 Fortuna C.G., Bonaccorso C., Bulbarelli A., Caltabiano G., Rizzi L., Goracci L., Musumarra G., Pace A., Palumbo-Piccionello A., Guarcello A., Pierro P., Cocuzza C. E. A., Musumeci R., Eur. J. Med. Chem. 2013,. 65, 533-545

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O-E3-02-01

COBALT(III) AS A STABLE AND INERT MEDIATOR ION BETWEEN NTA AND HIS6-TAGGED PROTEINS

Seraphine V. Wegner,1,2 Joachim P. Spatz.1,2

1 Max-Planck Institute for Intelligent Systems, Department of New Materials and Biosystems, Heisenbergstrasse 3, 70596, Stuttgart, Germany

2 University of Heidelberg, Department of Biophysical Chemistry, Im Neuenheimer Feld 253, 60120, Heidelberg, Germany


The Ni2+ mediated interaction between the hexahistidine tag (His6-tag) and nitrilotriacetic acid (NTA) has been shown to be a flexible and reliable chemistry to selectively bind recombinant proteins to NTA functionalized molecules and materials without disturbing the protein activity. However, the rather low affinity between the Ni2+-NTA and the His6-tagged protein, which is usually only in the micromolar range, and the kinetic lability of this complex, which therefore undergoes rapid ligand exchange limit its use. Here, we present Co3+ as a mediator ion for the enhanced interaction between NTA and His6-tagged proteins instead of the traditionally used Ni2+, Co2+ etc. Co3+ has two distinct advantages as a mediator ion: i) Co3+ forms thermodynamically drastically more stable complexes compared to Co2+ and Ni2+ in similar coordination environments. ii) Co3+ complexes are chemically inert towards ligand exchange reactions. We prepare the Co3+ complex between NTA and the His6-tag by first forming the Co2+ complex and then oxidizing the Co2+ center to Co3+. The resulting complex is chemically extremely inert and resistant towards strong chelators, low pH and reducing agents. Further, this complex undergoes very slow ligand exchange and has a half-life of 7 days under conditions where the analogous Ni2+ and Co2+ complexes are disrupted immediately. This system was be used to label His-tagged proteins with NTA conjugates and separate them from unlabeled His-tagged proteins with a Ni-NTA column by taking advantage of the kinetically inert interaction. Additionally, the properties of the Co3+ mediated interaction were used for the stable immobilization of proteins on nanomaterials and surfaces for cell culture applications.

Figure 1: Co3+ as a mediator ion between NTA and His6-tagged proteins forms a thermodynamically more stable and kinetically inert complex, unlike Ni2+ and Co2+.

References1. S. V. Wegner and J. P. Spatz, Angew. Chem. Intl. Ed. 52, 7593 (2013).

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O-E3-02-02

CLICK CHEMISTRY AT THE SURFACE OF BACTERIA

Jordi Mas Pons1, Audrey Dumont3, Gregory Sautejeau1, Emilie Fugier3, Aurélie Baron1, Annie Malleron2, Sam Dukan3 and Boris Vauzeilles1,2

1 ICSN, UPR-CNRS 2301, 1 avenue de la Terrasse, 91198 Gif-sur-Yvette, France.2 ICMMO, UMR-CNRS 8182, Université Paris-Sud, 91405 Orsay, France.

3 IMM, UMR-CNRS 7283, Université Aix Marseille, 13402 Marseille, France.Presenting Author: [email protected]

Sudden outbreaks of new epidemics regularly warn us against the severe sanitary and economical impact resistant bacterial infections could have on our globalized societies. The rapid identification of viable bacteria is therefore a fundamental challenge.

The outer membrane of Gram-negative bacteria is covered by a dense layer of Lipopolysaccharides (LPS), which are considered to participate into cell integrity, as well as to the level of pathogenicity of a given strain.

In this communication, we will show that, when they are metabolically active, Gram-negative bacteria can specifically incorporate into their LPS a monosaccharide, which has been modified by the introduction of an azido anchor. 1[1]

This bioorthogonal chemical reporter can then be further exploited in the click-chemistry mediated labeling of these bacteria, offering an efficient and rapid strategy to identify living, or metabolically active bacteria.

This communication will present our recent advances in this field, including the specific identification of Legionella pneumophila. 2[2]

1 1. Dumont, A., Malleron, A., Awwad, M., Dukan, S., Vauzeilles, B. Angew. Chem. Int. Ed., 51, 3143-3146 (2012).2 2. Mas Pons, J., Dumont, A, Sautejeau, G., Fugier, E., Baron, A., Dukan, S., Vauzeilles, B. Angew. Chem. Int. Ed., 53, 1275-1278 (2014).

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O-E3-02-03

BIOINORGANIC CHEMISTRY OF BRI2-23 AN NATURAL AMYLOIDβ AGGREGATION INHIBITOR

Marek Luczkowski1, Ricardo De Ricco2, Daniela Valensin2, 1Faculty of Chemistry, University of Wroclaw, 50-383 Wroclaw, Poland;

2Department of Chemistry, University of Siena, 53100, Siena, ItalyPresenting author: [email protected]

The studies on the metal ions involvement in neurodegenerative diseases has focused on their interactions with the signature proteins that play a major role in the progress of these neurological syndromes. The question of the metal ion involvement in the inhibition of the aggregation processes of amyloidβ, the hallmark of Alzheimer’s disease, has gained minor interest. The largest number of studies has been carried out with amyloidβ, the hallmark of Alzheimer’s disease. The peptide and its precursor protein are known to interact with number of protein partners located within or in close proximity to cellular membrane. BRI2 is type 2 transmembrane protein of unknown function, that consists of a 266 amino acid residues. It is expressed at high levels in the brain and cleaved by furin or furin-like proteases at its C-terminus to produce a 23 amino acid peptide (Bri2–23).[1,2] This product of proteolytic cleavage of BRI2 demonstrates an inhibitory effect on amyloid-β deposition in vivo and aggregation in vitro, thus indicating that BRI2 is a novel factor that modulates amyloid-β aggregation and deposition.[3] Since BRI2-23 incorporates the amino acid residues that are considered good metal binding sites (thiolates and imidazoles), our studies focused on examination of the peptide binding properties towards metal ions essential in biology of amyloid-β, with the special interest in Cu(I). Due to the fact that studies on Cu(I) are tremendously challenging, we used Hg(II) as molecular probe. That allow us comprehensive characterization of the system with the application of methods inaccessible to Cu(I) ions, like PAC spectroscopy. Herein we present the on the BRI2-23 structural properties of BRI23 and its Hg(II) complexes with special interest of metal tremendous impact on aggregation properties of the system.

AcknowledgementsWe thank National Science Center (NCN 2011/01/B/ST5/03936) and MIUR (PRIN 2008) for financial support.

References1. S-H. Kim et al, Nat. Neurosci. 2, 984 (1999).2. S. I. Choi et al, FASEB J. 18, 373 (2004).3. J. Kim et al, J. Neurosci. 28, 6030 (2008).4. B.M. Austen et al, Biochemistry 47, 1984 (2008).

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O-E3-02-04

Can Quantum Chemistry Methods Be Used to Describe Excited States of the Building Blocks of DNA?

Péter G. Szalay1

1A Laboratory of Theoretical Chemistry, Institute of Chemistry, Eötvös Loránd University, Budapest, Hungary


What happens with the DNA after UV irradiation? This question is asked not only by scientist, but even public interest is high due to health risks related to increased UV impact on earth surface. To understand all details of this process, the most logical route, both theoretically and experimentally, should start with the investigation of the nucleobases, the principal building blocks of DNA responsible for the absorbance of UV photons, and then continue with a systematic build-up of the natural DNA with sugar residues, hydrogen-bonded Watson-Crick pairing, π stacking, solvent effects, etc. If DNA is split in to small building blocks, even the highest level methods of quantum chemistry can be used to understand the basic processes [1].

Figure 1: Artistic representation of our project

Our prime interest is excited states, simulation of excitation spectra. We have calculated the excitation energy of nucleobases with the highest level methods available today. Then we added water, as well the sugar residue to see how the environment changes the property of the excited states. In the next step the dimers of nucleobases have been investigated: Watson-Crick pairs, and stacked π-π complexes. Here two types of excited states could be identified: a) local excitations on the nucleobases and b) charge transfer states. The former states are very much like those the monomers, while in the latter process an electron is transferred from one basis to the other. The excitation energy of these excitations are surprisingly low. Our ability to describe these processes with high level quantum chemical methods allows the investigation of charge transfer processes. And then very fascinating questions can be asked: can DNA conduct electric charge? I will not be able to answer this question now, but I will show our first results on the mechanism of charge transfer between neighbouring nucleobases.

References1. Szalay, P. G. Can Coupled-Cluster Methods Be Used to Describe Excited States of the Building Blocks of DNA? International Journal of Quantum Chemistry, 113(14), 1821–1827, (2013).

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O-E3-02-05

A NEW FAMILY OF ADAPTATIVE MACROCYCLES FOR MOLECULAR RECOGNITION

P.-T. Skowron1, M. Dumartin2, J. Leclaire2

1Aix Marseille University – iSm2 CNRS ECM UMR 7313Campus Scientifique St Jérôme Case 462, Av Escadrille Normandie-Niemen

13397 Marseille Cedex 20, FRANCE2ICBMS UMR CNRS 5246, Equipe Chimie Supramoleculaire Appliquee, Universite de Lyon,

Universite Lyon 1, 43 Boulevard du 11 Novembre 1918,69622, Villeurbanne, FRANCE

[email protected]

Dynamic Combinatorial Chemistry (DCC) [1] is a new and efficient way to design receptors capable of specific molecular recognition. By linking molecular building blocks together using a reversible and thermodynamically controlled reaction one can create Dynamic combinatorial libraries (DCLs). The addition of a guest to those DCL’s shifts the distribution towards the library member that binds optimally with the guest (figure 1).

Figure 1: Dynamic Combinatorial Chemistry

To do so, we designed a toolbox constituted of aromatic dithiols equipped with several functional groups. Libraries were prepared combining up those building blocks and various templates. Receptors based on such building blocks could adapt their size and function to optimize the binding to a molecular partner had to be brought (figure 2).

A NEW FAMILY OF ADAPTATIVE MACROCYCLES FOR MOLECULAR

RECOGNITION

P.-T. Skowron1, M. Dumartin2, J. Leclaire2 1Aix Marseille University – iSm2 CNRS ECM UMR 7313

Campus Scientifique St Jérôme Case 462, Av Escadrille Normandie-Niemen 13397 Marseille Cedex 20, FRANCE

2ICBMS UMR CNRS 5246, Equipe Chimie Supramoleculaire Appliquee, Universite de Lyon, Universite Lyon 1, 43 Boulevard du 11 Novembre 1918,

69622, Villeurbanne, FRANCE [email protected]

Dynamic Combinatorial Chemistry (DCC) [1] is a new and efficient way to design receptors capable of specific molecular recognition. By linking molecular building blocks together using a reversible and thermodynamically controlled reaction one can create Dynamic combinatorial libraries (DCLs). The addition of a guest to those DCL’s shifts the distribution towards the library member that binds optimally with the guest (figure 1).

Figure 1: Dynamic Combinatorial Chemistry To do so, we designed a toolbox constituted of aromatic dithiols equipped with several functional groups. Libraries were prepared combining up those building blocks and various templates. Receptors based on such building blocks could adapt their size and function to optimize the binding to a molecular partner had to be brought (figure 2).

Figure 2: Synthetic receptor obtain through DCC for spermine [2] References 1. P. T. Corbett, J. Leclaire, L. Vial, K. R. West, J.-L. Wietor, J.K.M. Sanders, S. Otto, Chem. Rev. 2006, 106, 3652–3711 2. L. Vial, R. F. Ludlow, J. Leclaire, S. Otto, J. Am. Chem. Soc. 2006, 128, 10253-10257

Figure 2: Synthetic receptor obtain through DCC for spermine [2]

References1. P. T. Corbett, J. Leclaire, L. Vial, K. R. West, J.-L. Wietor, J.K.M. Sanders, S. Otto, Chem. Rev. 2006, 106, 3652–37112. L. Vial, R. F. Ludlow, J. Leclaire, S. Otto, J. Am. Chem. Soc. 2006, 128, 10253-10257

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O-E3-02-06

MOLECULAR SIGNATURES OF G-PROTEIN COUPLED RECEPTORS

A. J. Venkatakrishnan1, X.Deupi2, G.lebon3, C. G. Tate1, G.F. Schertlier2, M. Madan Babu1

1MRC Laboratory of Molecular Biology, CB2 0QH, Cambridge, United Kingdom2 Paul Scherrer Institute, 5232, Villigen, Switzerland

3Institut de Génomique Fonctionnelle de Montpellier, 34094, Montpellier, FrancePresenting author: [email protected]

G-protein coupled receptors (GPCRs) are a large family of cell surface proteins that mediate the action of a broad spectrum of chemical ligands and pharmaceutical drugs. Recent crystal structures of several medically important GPCRs are charting the structural landscape of GPCRs and are defining the mechanisms of ligand binding and receptor activation. A systematic comparison of these structures reveals conserved molecular features of the GPCR family1. Firstly, we have uncovered a conserved three-dimensional network of non-covalent contacts between the transmembrane (TM) helices of the experimentally determined structures of GPCRs, irrespective of their functional conformational state. Based on sequence analysis of GPCRs in humans we show the residues constituting this network are more conserved than the rest of the TM residues, suggesting that this network forms an evolutionary core of the GPCR fold. Secondly, by studying the structures of different receptor ligand complexes we have identified a conserved “ligand-binding cradle” that forms the bottom of the ligand-binding pockets. This information of conserved ligand binding contacts can be exploited for fragment-based drug discovery and pharmacophore design of receptors with no solved structures. Lastly, we have identified non-covalent contacts that are maintained across different GPCRs in a conformation-dependent manner. These interactions are likely to represent the conformational signatures of GPCRs. The findings from this study have important implications for computational modeling of unsolved membrane proteins and for fragment-based drug discovery.

References

1 Venkatakrishnan, A. J. et al. Nature 494, 185-194(2013).

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O-F1F2-01-02

METABOLOMIC STUDY OF WILD AND OGM NICOTIANA LANGSDORFII PLANTS EXPOSED TO ABIOTIC STRESSES

E. Scalabrin1,3, A. Forlin1, M. Radaelli1, M. Ranaldo1, G. Toscano1, P. Bogani2, G. Capodaglio1,3

1Department of Environmental Sciences, Informatics and Statistics, University of Venice, Ca’ Foscari, Dorsoduro 2137, 30123 Venice, Italy

2Department of Biology, University of Florence, Via Madonna del Piano, 50019 Sesto Fiorentino (FI), Italy

3CNR-IDPA, Dorsoduro 2137, 30123 Venice, ItalyPresenting author:[email protected]

Plants have a considerable ability to deal with higly variable environmental stresses through the activa-tion of stress-specific tolerance mechanisms at different levels of organization [1]. As metabolites are the end-products of cellular functions, their presence and relative concentrations is the best indicators of an organism’s phenotype [2]. The metabolomic approach help to better understand the complexity of plant systems and which components play the most important role [3]. The aim of this study is to investigate the variation of the metabolic pattern when plants are subjected to different abiotic and biotic stresses, thus identifying the effects on the plant metabolism and their interactions. Samples of Nicotiana Langsdorfii plant were modified for two genes (ROLC from Agrobacterium rhizogenes and the rat GR receptor), which cause development variations in the host plants. Wild-type and OGM-type plants where then exposed to different environmental stresses (Cr(VI) exposition, water deficiency, high temperature) to evaluate the metabolic changes caused by single and multiple stresses. All plants were analyzed by HPLC-ESI-LTQ Orbitrap which allow to separate and detect hundreds of polar com-pounds simultaneously with high mass accuracy and resolution. The sample treatment protocol had the main purpose of recover the wider range of metabolites and was simplify as much as possible to avoid compound degradation or loss. Particular attention was posed on sample repeatability control:samples were analyzed in three replicate, to test repeatability of the analytical protocol, and an internal standard was added to check for possible variation in extraction and detection of the metabolites; blank and con-trol (pooled) samples were also produced at the same time to verify absence of contamination and the technical reproducibility of the instrumental method. The HPLC analysis was conducted with a C18 reversed-phase column with relative small molecular size to optimize chromatographic resolution; the MS data were collected in both polarity mode, to give a complete metabolic profile of the samples. Raw data were handled using a fully untargeted data processing workflow, followed by multivariate analysis techniques and identification of metabolites, particularly differing by stress type and modification type. This approach resulted in putative identification for more than 300 metabolites, among which well known key molecules involved in stress regulation, known plant metabolites and yet unknown com-pounds. The variation in the metabolic profile of the samples indicated a regulation both genetical and environmental of the phytochemistry of plants.

References1. Atkinson N.J. and Urwin P.E., J. Exp. Bot. 63, 3523-43 (2012)2. Glauser G., Veyrat N., Rochat B., Wolfender J. and Turlings T., J. Chromatogr A. 1292, 151 (2013)3. De Vos R., Moco S., Lommen A., Keurentjes J., Bino R., Hall R., Nat Protoc 2, 778 (2007)

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O-F1F2-01-03

The role of mass spectrometry in understanding and preventing food allergies

B. Prandi, T. Tedeschi, A. Dossena, S. Sforza

Department of Food Science, University of Parma, ItalyPresenting author: [email protected]

Food allergies are adverse reactions to certain food proteins that occur in previously sensitized (IgE me-diated) or genetically predisposed (not IgE mediated) subjects. The immunological reaction involves antibodies and cell mediators, and leads to a wide spectrum of symptoms (from mild gastrointestinal problems to systemic consequences). For the severity of these reactions the European Commission ap-proved the Directive 2007/68/EC, which lists all the allergenic foods that must be labelled in food prod-ucts. Allergen detection methods can be basically divided into PCR-based methods and ELISA-based methods [1], but in the recent years also mass spectrometry is increasing its diffusion for allergen anal-ysis. Different mass spectrometric approaches are being applied, both for allergens quantification and for allergens characterization from the molecular point of view. Identification of marker peptides allows an extremely specific quantification of allergenic proteins, through the addition of isotopically labeled analogues of the marker peptides or through an external matrix calibration curve. This approach was used to quantify both single proteins, for example the wheat allergens CM3 [2], and complex protein mixtures, like gluten proteins. Beside the detection aspects, linked to the safety of food products, mass spectrometry is a useful tech-nique to understand food allergy mechanism, for example by determining the resistance of different food allergens to gastrointestinal digestion. In fact, the higher allergenicity of peach LTP can be ex-plained on the basis of its higher resistance to proteolysis (30% of intact protein at the end of the diges-tion) compared to apricot LTP (9% intact protein). With LC-MS it has been possible also to identify the high molecular weight peptides generated, that are mainly constituted by the intact core of the protein still bound by 4 disulfide bridges. Celiac disease related peptides were also identified and quantified using the isotopically labeled internal standard method, demonstrating that different wheat lines can produce a significantly lower amount of immunogenic peptides upon digestion. The use of these lines in the formulation of wheat derived products (especially of baby food) could reduce the exposure to immunotoxic sequences thus reducing the risk of celiac disease in genetically predisposed subjects. On the opposite, other wheat allergens, such as CM3, are more affected by environmental condition: the allergen content in fact is significantly different among the different harvesting areas.Mass spectrometry has thus a fundamental role in the study of food allergens, both from the safety per-spective (as a tool for allergen detection) and in understanding the molecular features of food allergies.

References1. L. Monaci and A. Visconti, Trends Food Sci Tech, 21, 272-283 (2010)2. B. Prandi, A. Faccini, T. Tedeschi, G. Galaverna, S. Sforza, Food Chem, 140, 141-146 (2013)3. B. Prandi, L. Farioli, T. Tedeschi, E.A. Pastorello, S. Sforza, Rapid Commun Mass Specrom,

26, 2905-2912 (2012)

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O-F1F2-01-05

CATALYSIS WITH ANION−π INTERACTIONS

Yingjie Zhao, Sakai Naomi, Stefan Matile*

Department of Organic Chemistry, University of Geneva, 1211 Geneva 4, [email protected]

Anion-π interactions occur between anions and electron-deficient aromatic planes with positive quadrupole moments. Their ability to bind and transport anions has been studied recently.1 However, catalysis with anion-π interactions remains essentially unexplored. We here report experimental and theoretical evidence that anion-π interactions can contribute to catalysis.2,3 The Kemp elimination is used as a classical tool to discover conceptually innovative catalysts for reactions with anionic transition states. Significantly increasing transition-state stabilization with increasing π-acidity of the catalyst was observed. This demonstrates that anion-π interactions indeed contribute to catalysis. Then enolate chemistry, which is central in chemistry and biology, was studied.4 We provide direct experimental evidence that anion-π interactions can stabilize enolates by almost two pKa units. The addition of these anion-π stabilized reactive enolate intermediates to enones and nitroolefins occurs with transition-state stabilizations of up to 11 kJ mol-1(Figure 1). Then the synthesis of natural product coumarin was studied. This is an anionic cascade reaction covers Aldol condensation, elimination and transesterification. The result proved that cascade processes on the π-acidic surface are accelerated by anion-π interactions. These findings will stimulate the use of anion- π interactions in catalysis in the broadest sense.

Figure 1: Accelerating enolate chemistry with anion-π interactions.

References1. R. E. Dawson, A. Hennig and S. Matile, et al. Nat. Chem. 2, 533 (2010).2. Y. Zhao, Y. Domoto, E. Orentas, C. Beuchat, D. Emery, J. Mareda, N. Sakai and S. Matile, Angew.

Chem. Int. Ed. 52, 9940 (2013).3. Y. Zhao, C. Beuchat, Y. Domoto, J. Gajewy, A. Wilson, J. Mareda, N. Sakai and S. Matile, J. Am.

Chem. Soc. 136, 2101 (2014).4. Y. Zhao, N. Sakai and S. Matile, Nat. Commun. DOI: 10.1038/ncomms4911 (2014).

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O-F1F2-02-02

On the way to a sugar computer ‒ algorithm driven approach for chemical logic gate integrationTitle of the Abstract

M. Elstner1, A. Schiller1

1Friedrich-Schiller University Jena, Institute for Inorganic and Analytical Chemistry, Humboldtstr. 8, 07743 Jena, Germany


A sensing system that comprises a boronic acid receptor (BBV) and an anionic fluorescent dye can detect saccharides at physiological conditions [1].

The sugar sensor forms also a logic gate with the material implication function (IMP). The gate works with chemical input and generates a fluorescence output [1]. Material implication is a truth function from which all other Boolean operators can be constructed. All known logic circuits, such as half-adder or full-adder, can be reinterpreted by using only IMP and the trivial FALSE operation.We present a general applicable protocol to integrate an unlimited number of molecular logic gates to construct complex circuits in microwell plates. Automated dosing of chemicals circumvents most of the integration problems of molecular logic [2]. It provides an intrinsic signal (re)amplification and universal wiring opportunities. To wire between the gates (dashed line) we make use of an algorithm that translates the output from one gate/well in the input for the next gate/well: after detecting the fluorescence output of the gate k the algorithm generates pipetting commands from this signal. The information (input A = BBV, input B = fructose) is transferred to the gate k+1 via chemicals. We demonstrate the power of this approach by computing basic arithmetic operations and a tic–tac–toe gaming automata [3].

References1. M.Elstner, K. Weisshart, K. Müllen, A. Schiller, J. Am. Chem. Soc. 134, 8098 (2012).2. A. P. de Silva, S. Uchiyama, Nat. Nano. 2, 399 (2007).3. M. Elstner, J. Axthelm, A. Schiller, Angew. Chem. Int. Ed. DOI: 10.1002/anie.201403769

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O-F1F2-02-05

Site-directed spin labeling of sulfite oxidase using non-natural amino acids

Aaron Hahn1, Christopher Engelhard2, Christian Teutloff2, and Thomas Risse1

1 Institute of Chemistry and Biochemistry, Freie Universität Berlin, Takustr. 3, 14195 Berlin, Germany2 Department of Physics, Freie Universität Berlin, Arnimallee 14, 14195 Berlin


Various spectroscopic methods using site-directed labeling strategies such as fluorescence spectroscopy or EPR spectroscopy are currently used to investigate structural as well as functional properties of proteins. EPR spectroscopy in combination with site directed spin labeling (SDSL) has proven to be a valuable tool in this respect, both for globular as well as membrane proteins. Commonly, spin labels are introduced into proteins using cysteine residues. However, this strategy fails if proteins contain functionally important cysteines. A recent proof-of-principle study using T4 Lysozyme as a model system has shown that non-natural p-acetylphenylalanine binding the spin label through a ketoxime ligation can be used for SDSL [1]. In the prove of principle study a very stable protein, which does not contain any essential cysteine residues, namely T4 lysozyme was used. In this contribution we will present a site directed spin labeling study on human sulfite oxidase using non natural amino acieds. H-SO is a molybdo-enzyme, which not only carries an essential cysteine residue binding the Moco-cofactor hence requires the use of non natural amino acids but is also considerably more challenging in terms of stability. Within this contribution we will discuss challenges involved in the labeling of a more fragile protein using the less reactive ketoxime ligation in comparison to the disulfide linkage and will explore the information gained from the EPR line shapes of these spin labels in terms of structure determination, using mutations along a helical turn as an exploratory example. While the problem will be exemplified using EPR spectroscopy the results in terms of reactivity as well as structural perturbation of the native structure will hold also for other methods. In addition, doubly spin labeled proteins were used to determine distances between the spin labels using pulsed electron-electron double resonance (pELDOR/DEER) experiments. The distance distributions extracted from these measurements will be discussed in light of expectations based on geometric considerations based on the known crystal structure of a chicken analog. These measurements will also be discussed in terms of biophysical properties of the molecular such as the mechanism of co-factor insertion.

[1] M. R. Fleissner, E. M. Brustad, T. S. Kalai, C. Altenbach, D. Cascio, F. B. Peters, K. L. N. Hideg, S. Parker, et al., Site-directed spin labeling of a genetically encoded unnatural amino acid, Proc. Nat. Acad. Sci. 2009, 106, 21637.

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O-F1F2-02-06

PROBING THE SATURATION OF LIPIDS IN ACUTE MYELOID LEUKAE-

MIA CELLS TREATED WITH A NOVEL COMBINATION THERAPY

Joanna Denbigh1, Andrew Southam2, Farhat Khanim2, Roy Goodacre1 and Nick Lockyer1

1Manchester Institute of Biotechnology, University of Manchester, UK 2School of Biosciences, University of Birmingham, UK


Acute myeloid leukaemia (AML) is an aggressive cancer made up of dysfunctional cells from the myeloid lineage. Current treatment includes high grade chemotherapy, which has the disadvantage of being very toxic and thus poorly tolerated in a major cohort of elderly AML patients. Drug redeploy-ment represents an alternative to chemotherapy and involves the use of existing drugs for situations they were not originally designed for. It has recently been shown that the combination of the cholesterol lowering drug, bezafibrate, and the female contraceptive, medroxyprogesterone acetate (combination denoted BaP) shows anti-leukaemic activity with no observable haematological toxicity in patients [1]. Initial lipidomics analysis of BaP treatment in HL60 and K562 AML cell lines suggested the treatment down-regulates de novo phospholipid synthesis leading to an increase in the unsaturation of phospho-lipid acyl chains.Raman microspectroscopy is an optical technique in which the inelastic scattering of photons and subsequent changes in the vibrational state of molecules are probed. Information is obtained rapidly without disrupting the cell environment, ideal for observing cellular lipidomic changes [2].Time of flight secondary ion mass spectrometry (ToF-SIMS) is a powerful surface analysis technique which has seen much development in biological applications in recent years [3]. The emergence of such applications has been largely driven by instrument developments in the last decade in which cluster primary ion beams (Aun

+, Bin+, C60

+) have been employed instead of atomic ions such as Ga+ and Cs+. These polyatomic cluster ion beams are capable of generating higher secondary yields from molecular materials, particularly higher mass species and thus increase the sensitivity of the technique making ToF-SIMS a novel tool for probing the surface of biological materials. Recently there have been a number of reports into the localisation of metabolite and lipid species in various mammalian tissues using ToF-SIMS and other mass spectrometry imaging (MSI) techniques [4]. The unique advantage of SIMS amongst MSI techniques is its sub-cellular spatial resolution, potentially allowing single cell metabolite analysis.Data will be reported from a multidimensional investigation into the lipidome of AML whole cells. The aim of the project is to assess the application of ToF-SIMS, Raman microspectroscopy and LC-MS to provide new insights into the chemical effects of drug treatment in cellular membranes, in particular the observation of changes in saturation state of phospholipids at the cellular level.References1. Murray JA, Khanim FL, Hayden RE, Craddock CF, Holyoake TL, Jackson N, Lumley M, Bunce

CM, Drayson MT, British Journal of Haematology, 149 65-69 (2010).2. Schie, IW and Huser, T, Applied Spectroscopy, 67(8) 813-828 (2013).3. Fletcher, JS and Vickerman, JC, Analytical and Bioanalytical Chemistry, 396(1) 85-104 (2009).4. Passarelli, MK and Winograd, N, Biochimica et Biophysica Acta, 1811(11) 976-990 (2011).AcknowledgementsThis work was supported by the BBSRC and Leukaemia and Lymphoma Research Council.

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O-F1F2-03-01

FAST PROCESS FOR CONSTRUCTION OF AN EFFECTIVE ANTIFOULING LAYER ON A AU SURFACE VIA ELECTRODEPOSITION

Bor-Ran Li,1 Mo-Yuan Shen,1 Hsiao-hua Yu2, and Yaw-Kuen Li1

1 Department of Applied Chemistry, National Chiao Tung University, Hsinchu, Taiwan.2 Institute of Chemistry, Academia Sinica, Taipei, Taiwan.


Biosensors have drawn much attention because of their potential to improve greatly biomedical research,1,2 drug discovery,3 environmental monitoring,4 and diagnosis of many diseases.5. Yet, efficient methods for bio-conjugation on sensor chip and for leasing the non-specific interaction of biomolecule from sensor are remained to be solved. A new approach to directly modify the zwitterionic molecule, dimethylammonio propane-1-sulfonate (sulfobetaine or SB), on the Au surface of QCM chip via electrodeposition is demonstrated. The zwitterion-functionalized antifouling surface enables a decrease by 95 % of the adsorption of non-specific proteins from fetal bovine serum (FBS, 10 %).

Figure 1: Schematic illustration of the synthesis and deposition of antifouling zwitterion on gold electrode.

References

1. J. Wang, Chem. Rev., 2008, 108, 814-825.

2. Y. Liu, X. Dong and P. Chen, Chem. Rev., 2012, 41, 2283-2307

3. M.F. Templin, D. Stoll, M. Schrenk, P.C. Traub, C.F. Vohringer and T.O. Joos, Drug. Discov. Today, 2002, 7, 815-822.

4. F. Long, A. Zhu and H. Shi, Sensors, 2013, 13, 13928-13948.

5. B. R. Li, Y. J. Hsieh, Y. X. Chen, Y. T. Chung, C. Y. Pan and Y. T. Chen, J. Am. Chem. Soc., 2013, 135 16034-16037.

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O-F1F2-03-02

DNA based biosensor for an evaluation of damage to DNA by nanoparticles

Teodora Ignata,b, Viktor Gajdosb, Jana Blaskovicovab, Mihaela Kuskoa, Ján Labudab

aNational Institute for Research and Develompent in Micro- and Nanotechnology IMT-Bucharest, 126A, Erou Iancu Nicolae Street, 077190, Bucharest, Romania

bInstitute of Analytical Chemistry, Faculty of Chemical and Food Technology, Slovak University of Technology in Bratislava, Radlinského 9, 81237 Bratislava, Slovakia

e-mail: [email protected]

Due to unique physical properties, quantum dots (QDs ) and generally nanomaterials have received enormous attention for their applications in technology, medicine, cosmetics, and other areas. Nevertheless, potential toxicity of QDs is still of great interest and represents one of the major issues that limits their use in clinical studies (Derfus et al. 2004; Tang et al. 2013). In the present work, DNA-based biosensor composed of glassy carbon electrode and a surface-attached dsDNA layer was constructed and applied for the detection of damage to DNA by UV-C radiation (λ = 254 nm) both, in the absence and the presence of CdTe QDs of different size present as a colloid in the aqueous medium. The DNA biosensor response is based on square-wave voltammetric intrinsic signal of the guanine moiety as well as on the voltammetric response of the redox indicator [Fe(CN)6]

3-/4- in the solution. Depending on the QDs size, they have exhibited a significant effect on the degradation of dsDNA by UV-C and even daily light. Time depending deep DNA structural changes include opening of the helix indicated by an increase in the guanine moiety response due to its redox correspondence with the electrode and by an increase in the voltammetric peak current of the [Fe(CN)6]

3-/4- anion after degradation of the negatively charged DNA layer at the electrode.The QDs behavior has been verified using two types of dsDNA (salmon sperm and calf thymus) and confirmed also by experiments with irradiation of DNA solution in the presence of QDs. Test of other nanomaterials are in progress. By this study, potentialities of the DNA biosensor and DNA biosensing for toxicologic investigations will be documented.

AcknowledgementThis work was supported by the Scientific Grant Agency VEGA of the Slovak Republic (Project No 1/0361/14) and the National Scholarship Programme of the Slovak Republic (Dr.Teodora Ignat).

ReferencesDerfus AM, Chan WCW, Bhatia SN (2004) Nano Letters 4: 11-18.Tang Y, Han S, Liu H, Chen X, Huang L, Li X, Zhang J (2013) Biomaterials 34: 8741-8755.

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O-F3-02-02

DUAL-FUNCTIONALIZED NANOSTRUCTURED BIOMIMETIC SURFACES

Franziska C. Schenk1,2, Heike Böhm1,2, Joachim P. Spatz1,2, Seraphine V. Wegner 1,2

1Max-Planck- Institute for Intelligent Systems, Department of New Materials and Biosystems, Heisenbergstraße 3, 70569 Stuttgart, Germany

2University of Heidelberg, Department of Biophysical Chemistry, ImNeuenheimer Feld 253, 69120 Heidelberg, Germany


Cellular events depend on the cross talk of multiple chemical signals in their environment. Therefore, complex materials that present more than one signaling molecule in a controlled manner are required to investigate cell response to various signaling molecules and the mutual influence of different factors. Here we present a dual-functionalized substrate as new platform for cell adhesion studies consisting of hexagonally arranged gold nanoparticles with defined spacing and a clickable PEG-alkyne coating in the intermediate space. Both, the gold nanoparticles and the PEG-alkyne layer can be orthogonally functionalized with a variety of different ligands by gold-thiol chemistry and copper catalyzed azide alkyne cycloaddition (CuAAC) respectively. The density of the presented ligands can also be varied by changing the interparticle distance between the gold dots and by adjusting the density of the clickable PEG-alkyne. Additionally, the intrinsic protein repellent properties of the PEG-alkyne layer prevent any other non-specific interactions of the cell with the substrate. Exemplarily, we investigated the cell adhesion of rate embryonic fibroblasts (REF) on substrates that present the adhesion peptide cRGD on the gold dots (100 nm interparticle spacing) and the synergy peptide PHSRN on the PEG alkyne coating (10 mol%). While REF cells do only adhere weakly to surfaces that present one of the two peptides, they adhere well on surfaces that present both peptides at the same time forming mature focal adhesions. The here presented dual functionalized nanostructured surfaces can be used to investigate the cross-talk between many other singling events in the cell and understand the clustering of receptors.

GlassAu Au Au Au

SS S SPEG-alkyne

N

N

N N

N

NN

N

N N

N

N N

N

NN

N

N

Signal 1 Signal 2Cross-talk

Figure 1: Cell adhesion on dual-functionalized nanostructured biomimetic surfaces.

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O-F3-02-03

NANOPARTICLE PREPARATION OF CURCUMIN ANTIOXIDANT BY LASP METHOD IN MICROCHANNELS

P. Valeh-e-sheyda1, M. Rahimi1, H. Adibi2

1 CFD Research Center, Chemical Engineering Department, Razi University, Kermanshah, Iran2 Novel Drug Delivery Research Centre, Faculty of Pharmacy, Kermanshah University of Medical

Sciences, Kermanshah, IranPresenting author: [email protected]

Curcumin is a natural polyphenol compound with many important pharmacological properties. In spite of its efficacy, it has not yet been approved as a therapeutic agent, since it is a poorly water-soluble hydrophobic drug. Curcumin dissolution rate can be improved by decreasing its particle size. The present investigation is aimed to improve curcumin particle size via liquid anti-solvent precipitation (LASP) process in microchannels (MCRs). For this purpose, a series of stabilizers were employed to screen their role on controlling growth and agglomeration of formed nanoparticles. The stabilizers namely includ-ed Low molecular weight hydroxyl propyl methyl cellulose (HPMC), Sodium dodecylsulfate (SDS, C12H25NaO4S) Hexadecyl trimethyl ammonium bromide (T-Tab, C19H42BrN), 1-ethenylpyrrolidin-2-one (PVP, C6H9NO)n, and Polysorbate 20 (Tween20, C58H114O26).

Particle size distribution (PSD), surface area and zeta potential were employed to characterize the precipitated nanoparticles. It was found that in a precipitation system involving PVP, homogeneity of curcumin concentration provides a uniform particle size distribution. In particular, curcumin precipitated from PVP 0.03% and PVP 0.3% demonstrated the smallest stable particle sizes.

NANOPARTICLE PREPARATION OF CURCUMIN ANTIOXIDANT BY LASP

METHOD IN MICROCHANNELS

P. Valeh-e-sheyda1, M. Rahimi1, H. Adibi2 1 CFD Research Center, Chemical Engineering Department, Razi University, Kermanshah,

Iran 2 Novel Drug Delivery Research Centre, Faculty of Pharmacy, Kermanshah University of

Medical Sciences, Kermanshah, Iran Presenting author: [email protected]

Curcumin is a natural polyphenol compound with many important pharmacological properties. In spite of its efficacy, it has not yet been approved as a therapeutic agent, since it is a poorly water-soluble hydrophobic drug. Curcumin dissolution rate can be improved by decreasing its particle size. The present investigation is aimed to improve curcumin particle size via liquid anti-solvent precipitation (LASP) process in microchannels (MCRs). For this purpose, a series of stabilizers were employed to screen their role on controlling growth and agglomeration of formed nanoparticles. The stabilizers namely included Low molecular weight hydroxyl propyl methyl cellulose (HPMC), Sodium dodecylsulfate (SDS, C12H25NaO4S) Hexadecyl trimethyl ammonium bromide (T-Tab, C19H42BrN), 1-ethenylpyrrolidin-2-one (PVP, C6H9NO)n, and Polysorbate 20 (Tween20, C58H114O26). Particle size distribution (PSD), surface area and zeta potential were employed to characterize the precipitated nanoparticles. It was found that in a precipitation system involving PVP, homogeneity of curcumin concentration provides a uniform particle size distribution. In particular, curcumin precipitated from PVP 0.03% and PVP 0.3% demonstrated the smallest stable particle sizes.

Figure 1: Particle size distribution of curcumin precipitated by LASP at different concentrations of stabilizers

0 100 200 300 400 500

stabilizer free PVP 3%

PVP 0.3 % PVP 0.03%

SDS 3% SDS 0.3 % SDS 0.03% T-Tab 3%

T-Tab 0.3 % T-Tab 0.03%

HPMC 3% HPMC 0.3 % HPMC 0.03% Tween20 3%

Tween20 0.3 % Tween20 0.03%

Average Size (nm)

Stab

ilize

r

Figure 1: Particle size distribution of curcumin precipitated by LASP at different concentrations of stabilizers

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O-F3-02-04

NO AND CO RELEASING MATERIALS

A. Schiller Friedrich Schiller University Jena, Humboldtstr. 8, 07743 Jena, Germany

[email protected]

Nitric oxide (NO) and carbon monoxide (CO) act as messenger molecules in the human body.[1] NO- and CO-releasing materials (NORMAs & CORMAs) are important for the development of safe gas-otransmitter delivering devices for therapeutic purposes; toxic metabolites after gas release are kept in the biocompatible polymer matrix.[8] NO and CO photodonors use light as a convenient non-invasive on/off trigger since it allows the accurate control of site, timing and dosage.[2] Here we report the con-cept of embedding water-insoluble, photoactive NO and CO metal complexes into nanoparticles and fibrous polymer non-wovens.[3] NO and CO release into the surrounding medium is performed by light stimulation of the high surface area materials.

Metal nitrosyl or carbonyl complexes were non-covalently embedded into the polymer matrices via miniemulsion technique or electrospinning.[4,6,7] Especially dimanganese decacarbonyl in electro-spun poly(L-lactide-co-D/L-lactide) fibers revealed nanoporous morphologies. A slight CO release from the metal complex induced nanoporosity in the electrospinning process.[5,7] Irradiation with light between 366 and 480 nm in water triggered NO/CO release from the nanoparticles or non-wovens.[4-7] With CORMA the cytotoxicity tests with 3T3 mouse fibroblast cells in the dark revealed a very low mortality rate. After illumination, CO bubbled out of the nanofibers thereby eradicating fibroblast cell cultures[7] or biofilms with methicilin-resistant Staphylococcus aureus (MRSA).[8]

References:[1] S. H. Heinemann, T. Hoshi, M. Westerhausen, A. Schiller, Chem. Commun. 2014, 50, 3644-3660. [2] D. Crespy, K. Landfester, U. S. Schubert, A. Schiller, Chem. Commun. 2010, 46, 6651-6662. [3] A. Schiller, in Molecules at Work. Selfassembly, Nanomaterials, Molecular Machinery, (Ed.: B. Pigna-taro), Wiley-VCH, Weinheim, 2012, 315-338. [4] C. Bohlender, M. Wolfram, H. Görls, W. Imhof, R. Menzel, A. Baumgärtel, U.S. Schubert, U. Müller, M. Frigge, M. Schnabelrauch, R. Wyrwa, A. Schil-ler, J. Mater. Chem. 2012, 22, 8785-8792. [5] R. Wyrwa, M. Schnabelrauch, C. Altmann, A. Schiller, DE10 2012 004 132.2, PCT patent pending. [6] C. Bohlender, K. Landfester, D. Crespy, A. Schiller, Part. Part. Syst. Charact. 2013, 30, 138-142. [7] C. Bohlender, S. Gläser, M. Klein, J. Weisser, S. Thein, U. Neugebauer, J. Popp, R. Wyrwa, A. Schiller, J. Mater. Chem. B 2014, 2, 1454-1463. [8] DFG research unit FOR 1738, www.hhdp.uni-jena.de.

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O-F3-03-02

NANOMATERIALS AS AN EMERGING ENVIRONMENTAL CONTAMINANT: COMPARISON OF RISK ASSESSMENT METHODS

D. G. Rickerby1, I.M. Rio Echevarria 1

1European Commission Joint Research Centre, Institute for Environment and Sustainability, 21027 Ispra VA, Italy


The unknown risks of nanomaterials require an integrated approach to risk assessment and safety management. Existing methods for risk assessment of chemicals and hazardous wastes may not be adequate to deal with their large-scale production and use. Specific methodologies and tools need therefore to be developed for assessment and management of risks related to manufactured nanomaterials. Exposure due to release during the entire life cycle, including production, use and final disposal or recycling is a key parameter determining the level of risk. However, there is at present rather limited knowledge concerning the extent to which nanomaterials are likely to be released or how they are transported, transform or accumulate in the environment [1]. There are data gaps with regard to the physicochemical properties of nanomaterials and the amounts released at each stage of the life cycle, while large variability occurs in the estimated concentrations in the environmental compartments as a result of the uncertainties in production volumes [2, 3].

The present work considers some appropriate methodologies and tools to assess and manage the environmental and health risks due to manufactured nanomaterials [4]. The nanomaterials investigated include organic and inorganic nanomaterials and associated products: titanium dioxide nanoparticles; zinc oxide nanoparticles; carbon nanotubes; nanocellulose. Potential releases during industrial processing and disposal at end of life or recycling were examined. These studies were intended to assist in estimating exposure to reduce the uncertainly in risk assessment. An important aspect is to determine where nanomaterials present environmental and health hazards that differ from those for conventional chemicals and therefore where the challenges for risk assessment are likely to be greatest. The current scientific knowledge on characterisation, detection, measurement, transport, toxicology, exposure, persistence and fate is still insufficient to allow accurate prediction of their impact on the environment and human health [5]. However, the increasing amount of nanomaterials being produced worldwide raises important questions about their behaviour when released into the environment and consequent health hazards.

References1. D.E. Meyer, M.A. Curran, M.A. Gonzalez, Environ Sci. Technol 43,1256-1263 (2009).2. N.C. Mueller and B. Nowack, Environ. Sci. Technol. 42, 4447-4453 (2008).3. C.O. Hendren, X. Mesnard, J. Dröge and M.R. Wiesner, Environ. Sci. Technol. 45, 2562-2569 (2011).4. D.R. Hristozov, S. Gottardo, A. Critto and A. Marcomini, Nanotoxicol. 6, 880-898 (2012).5. S.J. Klaine, P.J.J. Alvarez, G.E. Batley, T.F. Fernandes, R.D. Handy, D.Y. Lyon, S. Mahendra, M.J. McLaughlin and J.R. Lead, Environ. Technol. Chem. 27, 1825-1851 (2008).

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O-F3-03-03

Chemical Modification of Silk Fibroin for Making Novel Specialty Biomaterials

R. Watanesk and S. Watanesk

Department of Chemistry, and Materials Science Research Center, Faculty of Science, Chiang Mai University, Chiang Mai 50200, Thailand.


Our research projects aim on the improvement and value enhancement of the natural material remains in order to utilize them through modifying their structures chemically. Currently we focus our work on the chemical modification of fibroin from silk (Bombyx mori) cocoons for applying as biomaterials. Silk fibroin (SF) is a biodegradable natural polymer which has unique properties including non-toxicity, biocompatibility and bio-degradability. It has been utilized in many areas such as food industrial, pharmaceutical and medical applications. However, SF film in dry state is not suitable for use by itself because of its brittleness. Therefore, the SF-based films were generated by blending the SF solution with other biopolymers such as rice starch (RS) and gelatin in order to develop a novel specialty blend. In the case of blending with RS, the interactions within the blend occur through the crosslinking between SF and RS networks as indicated by the FT-IR spectra. Such interaction occurs between the -NH- groups of SF and the -OH groups of RS that make the SF-RS blended film become more flexible with lower tensile strength than the SF itself. Whereas there is no intermolecular interactions taken place between gelatin and SF moieties in the SF-gelatin blend. However, the addition of gelatin helps improve the flexibility of the SF-gelatin by forming as hydrogels which can be evidently seen by the decrease of their crystallinity determined from the XRD patterns. Therefore, both SF-RS blended film and SF-gelatin hydrogel can accommodate more water molecules, thereby increasing their water swelling. These results indicate a potential for preparing the SF-based biomaterials that could be utilized in various applications.

SF

RS

SF-RS(5:95)

SF

SF-Gelatin(75:25)SF-Gelatin(50:50)SF-Gelatin(25:75)

Figure 1: FT-IR spectra of SF, RS and SF-RS films

Figure 2: FT-IR spectra of SF and SF-gelatin hydrogels

References1. P. Kuchaiyaphum, W.Punyodom, S. Watanesk and R, Watanesk, J. Appl. Polym. Sci. 129, 2614-

2620 (2013).2. A. Rattanamanee, H. Niamsup, L. Srisombat, R. Watanesk and S. Watanesk, Adv. Mater. Sci.,

750-752, 1347-1353 (2013).3. A. Racksanti, S. Janhom, S. Punyanitya, R. Watanesk and S. Watanesk, Appl. Mech. and Mater.,

446-447, 366-372 (2014).

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O-F4-01-02

The analytical application of the photo-CIDNP MAS NMR effect

I. F. Céspedes-Camacho1, J. Matysik1

1Institüt für Analytische Chemie, Universität Leipzig, Linnéstr. 3, 04103 Leipzig, GermanyPresenting author: [email protected]

In order to enhance the signal intensity and improve the sensitivity of NMR spectroscopy, several non-Boltzmann hyperpolarization methods have been developed. One of them is the photochemically induced dynamic nuclear polarization (photo-CIDNP), described by the classical radical pair mechanism (RPM). In solid state, the photo-CIDNP effect has been observed since its discovery in 1994 in several photosynthetic reaction centers (RC) by magic angle spinning (MAS) NMR [1]. Enhancement factors of above 80000 have been observed in the photosynthetic RC of the purple bacteria Rhodobacter (Rb.) sphaeroides (Figure 1). This effect can be explained by a combination of several mechanisms (e.g. three-spin mixing, differential decay and differential relaxation) [2]. The basic idea is transfer the electron spin polarization obtained in the initial singlet radical pair to nuclei via hyperfine interactions.

Besides the standard NMR information, the photo-CIDNP MAS NMR effect allows to study local dynamics and electronic structure of the RCs (i.e. local electron spin densities) [3,4]. It is also possible to obtain kinetic information (time-resolved experiments), distance of cofactors and details about the singlet and/or triplet excited states precursors. Therefore, this hyperpolarization method can be used as an important tool on the spin chemistry research and topics related.

Figure 1: 13C MAS NMR spectra of the RC of Rb. sphaeorides R26 in the dark (black) and under illumination (red) at 17.6 T (A), 9.4 T (B), 4.7 T (C) and 2.4 T (D).

References1. M. Zysmilich and A. McDermott, J. Am. Chem. Soc. 116, 8362 (1994).2. G. Jeschke and J. Matysik, Chem. Phys. 294, 239 (2003).3. E. Daviso, S. Prakash, A. Alia, P. Gast, J. Neugebauer, G. Jeschke and J. Matysik, Proc. Natl. Acad.

Sci. U.S.A. 106, 22281 (2009).4. S. S. Thamarath, B. E. Bode, S. Prakash, K. B. S. S. Gupta, A. Alia, G. Jeschke and J. Matysik, J.

Am. Chem. Soc. 134, 5921 (2012).

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O-F4-02-02

ENANTIOMERIC DISCRIMINATION OF ISOXAZOLINE FUSED B-AMINO ACID DERIVATIVES USING (+)-(18-CROWN-6)-2,3,11,12-

TETRACARBOXYLIC ACID AS A CHIRAL NMR SOLVATING AGENT

J. Howard1, M. Nonn2, F. Fülöp2, T. Wenzel.1

1Bates College, 04240, Lewiston, ME, USA2University of Szeged, H-6701, Szeged, HungaryPresenting author: [email protected]

Optically active b-amino acids and isoxazolines have recently received a lot of attention due to their strong pharmacological potential as antibiotic, antifungal, and antiviral agents. Synthesizing these compounds in a stereoselective manner are complex and commonly result in a mixture of enantiomers. Prior studies have shown that optically pure (18-crown-6)-2,3,11,12-tetracarboxylic acid (18-C-6-TCA) is a useful chiral NMR solvating agent for substrates containing amine groups. In this study, racemic mixtures of isoxazoline fused b-amino acid derivatives were analyzed using 18-C-6-TCA and nuclear magnetic resonance (NMR) spectroscopy. The crown ether associates with the substrate through the formation of three hydrogen bonds between the protonated amine and crown ether oxygen atoms. Enantiomeric discrimination is observed for two or more resonances of every substrate. At least one of these resonances is free of overlap with other resonances in the spectrum and has a large enough enantiomeric discrimination to enable the determination of enantiomeric purity. Furthermore, 2D COSY methods can be used to identify additional resonances that exhibit enantiomeric discrimination in the NMR spectrum. Herein we report successful enantiomeric discrimination of these compounds and the increased applications of 18-C-6-TCA as a useful chiral NMR solvating agent for highly functionalized b-amino acids.

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O-F4-03-01

BEAD INJECTION CONCEPT FOR SAMPLE PREPARATION

M. A. Segundo

REQUIMTE, Department of Chemical Sciences, Faculty of Pharmacy, University of Porto, Rua de Jorge Viterbo Ferreira, 228, Porto 4050-313, Portugal


One of the major problems upon automation and integration of sample treatment with techniques targeted to analyte determination is the robustness and repeatability of currently available approaches. This is an important issue in sample treatment prior to chromatographic analysis, where packed bed columns are applied to selectively retain analytes that are further desorbed using the mobile phase or appropriate solvents. Nevertheless, these columns are susceptible to fouling and contamination after the processing of consecutive samples, especially those comprising complex matrices.In this context, the bead injection concept is the perfect tool to address this issue. The bead injection (BI) technique was proposed in the 1990s by Jarda Ruzicka [1], aiming the automation of solid-phase chemistry with the possibility of renewal through microfluidic handling of beads. The beads can be carriers of different (bio)chemical moieties, fostering the development of sensors for enzymatic and immunochemical assays. Moreover, solid-phase extraction (SPE) procedures can be simply implemented and miniaturized using the BI concept within a lab-on-valve (LOV) device. Considered as the third generation of Flow Injection Analysis, LOV is based on a monolithic structure with microconduits machined in a polymeric block, mounted atop a multiposition selection valve. Due to the mesofluidic scale of these channels, LOV systems present more potential and compatibility with real-world samples when compared to microfluidic devices [2].In the present communication, the implementation of automatic analytical protocols using the bead injection concept will be addressed with special emphasis to miniaturization of SPE protocols. In fact, all SPE steps, including analyte elution, may be attained under the LOV format, with further column renewal and sorbent disposal through software control. The possibility of introducing the eluate in other instrument/device (e.g. liquid chromatograph) for further processing and analysis will be discussed and illustrated by application to real samples, emphasizing the potential of this approach towards Green Analytical Chemistry.

AcknowledgementsThis work received financial support from the European Union (FEDER funds through COMPETE) and National Funds (FCT, Fundação para a Ciência e Tecnologia) through project Pest-C/EQB/LA0006/2013, from FEDER funds under the framework of QREN through Project NORTE-07-0124-FEDER-000067, and from the North Portugal Regional Operational Programme (ON2) in the National Strategic Reference Framework (NSRF) through NEPCAT, nr. 38900.

References1. J. Ruzicka, L. Scampavia, Anal. Chem. 71, 257A-263A (1999).2. M. Miró, H.M. Oliveira, M.A. Segundo, Trac-Trends Anal.Chem. 30, 153-164 (2011).

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O-F4-03-02

Versatile in situ gas analysis apparatus for nanomaterials reactors

S. S. Meysami1, L. C. Snoek1, N. Grobert1

1Department of Materials, University of Oxford, Parks Road, Oxford OX1 3PH, United KingdomPresenting author: [email protected]

We report a newly-developed technique for the in situ real-time gas analysis of reactors commonly used for the production of nanomaterials, by showing results obtained from a dedicated apparatus [1] capable of measuring the gas composition in reactors operating at high temperature (<1000°C). The in situ probe allows a more accurate study of the mechanism of progressive thermocatalytic cracking of precursors, compared to the previously-reported conventional residual gas analysis of the reactor exhaust [2, 3], and hence paves the way for the controlled production of novel nanomaterials with tai-lored properties (Figure 1). Our studies demonstrate that the composition of nanomaterials precursors dynamically changes as they travel inside of the reactor and therefore causing non-uniform growth [4]. Moreover, mapping of the nanomaterials reactor using quantitative gas analysis revealed the actual contribution of thermocatalytic cracking and quantification of individual precursor fragments. This information is particularly important for quality control of the nanomaterials and the recycling of ex-haust residues, ultimately leading towards a greener and more cost-effective continuous production of nanomaterials in large quantities. A case study of multi-wall carbon nanotube synthesis was conducted using the probe in conjunction with chemical vapour deposition (CVD) techniques. Furthermore, given the similarities of this particular CVD setup to other CVD reactors and high-temperature set-ups gener-ally used for nanomaterials synthesis, the concept and methodology of gas analysis presented here does also apply to other systems, making it a versatile and widely applicable method across a wide range of materials manufacturing methods, catalysis as well as reactor design and engineering.

Figure 1: Schematic of an in situ gas analysis probe for nanomaterials manufacturing.

References1. S. S. Meysami and N. Grobert, patent publication no.: WO/2013/030544 (2013).2. S. S. Meysami, A. A. Koós, F. Dillon and N Grobert, Carbon 58, 159 (2013).3. S. S. Meysami, Development of an aerosol-CVD technique for the production of CNTs with integrat-ed online control (PhD thesis, University of Oxford, Oxford 2013).4. S. S. Meysami, F. Dillon, A. A. Koós, Z. Aslam and N. Grobert, Carbon 58, 151 (2013).

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O-F4-03-03

SIMULTANEOUS MULTI-ELEMENT DETERMINATION OF BERYLLIUM, CHROMIUM, AND COPPER BY GRAPHITE FURNACE ATOMIC

ABSORPTION SPECTROMETRY

K. M. Elsherif1 and H-M Kuss2

1Benghazi University, Faculty of Science, Chemistry Department, Benghazi, Libya2Duisburg-Essen University, Faculty of Chemistry, Instrumental Analytical Chemistry Department,

Essen, [email protected]

Direct and simultaneous determinations of Be, Cr, and Cu in different biological samples using a multi-element electrothermal atomic absorption spectrometer (Perkin-Elmer SIMAA 6000) are described. Pd(NO3)2 + Mg(NO3)2 mixture modifier was tested. The electrothermal behavior of the elements in single-element and multi-element mode (with and without modifiers) was studied. The pyrolysis and atomization temperatures for the simultaneous determination using the mixture modifier were 1200 and 2300oC. A standard reference material (Seronorm Trace Elements Urine) was used to find the optimal temperature program. The reliability of the entire procedure was confirmed by analysis of certified reference materials as Trace Elements Urine Sample (from Seronorm 05115459 and from BIO-RAD 69061), Bovine Liver (from NIST 1577b), and Tea sample (from GBW 8505). Standard additions method was used to determine Be, Cr, and Cu in the samples simultaneously. Results of analysis of standard reference materials were in agreement with certified values. The analyzed values were in the range of: 91.7-103.2 % for Be, 90.0-102.0 % for Cr, and 86.0-101.1 % for Cu. The detection limits were 0.036-0.057 μg.l-1 for Be, 0.070-0.081 μg.l-1 for Cr, and 0.21-0.44 μg.l-1 for Cu. The Characteristic masses were 2.5-7.3 pg for Be, 5.9-10.9 pg for Cr, and 18.7-32.6 pg for Cu. The relative standard deviations (RSD) of the non spiked sample measurements were in the range: 1.1-9.1 % for Be, 0.4-4.9 % for Cr, and 0.2-3.3 % for Cu.Keywords: Multi-Element, Graphite Furnace, Be, Cr, Cu

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O-F4-03-04

FI-ICP-OES Determination of Rare Earth Elements in Environmental Samples Using Dispersed Particle Extraction with Surface Functionalized Magnetic

Nanoparticles

S. Hossein Zadegan1, W. Nischkauer 1, 2, M.-A. Néouze3 and A. Limbeck1

1 Vienna University of Technology, Getreidemarkt 9, 1060 Vienna, Austria.

2 Ghent University, Krijgslaan 281 / S12, 9000 Ghent, Belgium.

3 Ecole Polytechnique, 91128 Palaiseau, France.Presenting author: [email protected]

Differences in local abundance of rare earth elements (REEs) provide the possibility for geochemical fingerprints used, e.g. in oil extraction missions. Due to increased anthropogenic emissions of REEs, also investigation regarding the toxicity of these elements have gained more interest lately [1]. However, it is necessary to enrich these naturally low concentrated elements to gain high sensitivity and selectivity of spectrometry’s methods such as ICP-OES or ICP-MS. Solid phase extraction (SPE) is the most commonly applied enrichment procedure, but because of acclaimed disadvantages with the use of SPE columns, we recently introduced an improved method called dispersed particle extraction (DPE) [2,3]. With DPE, there is no need to elute the adsorbed REE cations from the SPE sorbent material using strong solvents. Instead, the slurry of adsorbed analytes on functionalized sub-micron silica particles is directly introduced into the plasma. Thus, higher recoveries and less variability in results were achieved [3].

In the here presented contribution, we propose a flow-injection (FI) system with ICP-OES detection for on-line determination of REEs in aqueous solutions using magnetic particles in combination with DPE. Silica coated cobalt nanoparticles with sulfonyl groups on their surface are suspended into the pH-adjusted sample digests. REEs are thereby retained on the functionalized particles. With the use of a FI-system, a defined volume of sample slurry is introduced into a strong magnetic field, where the analyte-loaded particles are trapped. After replacing the sample solution by a rinse solution, the collected particles are promptly released and the nanoparticles including the adsorbed REEs are introduced into the ICP-OES. Thus, a separation of sample matrix and analytes is possible, accompanied by a significant pre-concentration. The developed procedure has been applied for the determination of REEs in different environmental samples.

References1. X. Li, et al, Chemosphere. 93, 1240 (2013).2. G. Bauer, M.-A. Neouze and A. Limbeck, Talanta. 103, 145 (2013).3. R. Janski, M.-A. Neouze and A. Limbeck, Rapid Communications in Mass Spectrometry. 28, 1329 (2014).

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O-F4-03-05

Low Voltage Electrically Stimulated Lab-On-a-Chip Device Followed by RGB Analysis: A Simple and Efficient Design for Complicated Matrices

Shahram Seidia, Maryam Rezazadehb, Niki Zamanic, Sara Esmailic

aDepartment of Analytical Chemistry, Faculty of Chemistry, K.N. Toosi University of Technology, Tehran, Iran bDepartment of Chemistry, Tarbiat Modares University, Tehran, Iran

cFarzanegan 1 Educational Center, National Organization for Development of Exceptional Talents, Tehran, Iran


In the present work, a simple and portable analysis device was designed for the first time for determination of lead ion as model analyte. The basis of lead analysis is its extraction and preconcentration in an acceptor droplet via application of electrical field. The acceptor droplet is a KI solution and therefore, formation of yellow precipitation of PbI2 is the sign for presence of lead ion in the solution. Following that, the digital picture of final acceptor droplet was analyzed by investigating its RGB colorants. Results show that the RGB intensities of acceptor phase is proportion to lead concentration in the sample solution. Also, a 9.0 V battery was used to apply the electrical field and other effective parameters such as type of organic liquid membrane, pH of sample solution and extraction time was considered to reach the optimal conditions. The model analyte was determined by extracting from 100 µL sample solution across a thin layer of 1-octanol, immobilized in the pores of a polypropylene membrane sheet, and into acceptor droplet via applying a 9.0 V electrical potential for 20 min. The device is capable of determining the lead ion down to 20.0 ng mL-1 with admissible repeatability and reproducibility (intra- and inter-assay precision ranged between 3.8-7.0% and 9.8-11.9%, respectively). The linearity was studied in the range of 50.0-1500 ng mL-1 with acceptable correlation coefficients (regarding different red, green and blue colorants). Ultimately, the designed device was employed for analysis of lead in real samples.

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O-F4-04-02

A PROBING NANOPARTICLE INTERACTIONS WITH BIOLOGICAL SYSTEM FOR DRUG DELIVERY APPLICATIONS

B. Cattoz1, P. Griffiths1

1Department of Pharmaceutical, Chemical and Environmental Sciences, Faculty of Engineering and Science, University of Greenwich, Medway Campus, Central Avenue, Chatham Maritime Kent ME4

4TB, UK

Before any drug administered to the gastro-intestinal tract reaches the epithelium, it must traverse a layer of mucus. The main polymeric component of mucus is the glycoproteins collectively called mucins. These are complex gel-forming polymers which exhibit electrostatic, hydrophobic and H-bonding interactions and are responsible for the viscous and elastic gel-like properties of the mucus layer. The efficacy of nanoparticles (NPs) to penetrate this layer, and deliver macromolecular drugs in therapeutic concentrations to the epithelium will depend on the surface chemistry (decoration) of the NPs. Quantifying the interactions between these NPs and the mucin gel is essential for designing successful drug delivery systems. In this project various decorations were fabricated, including zeta potential changing, slippery, and proteolytic enzymes. Figure 1 illustrates slippery and proteolytic enzyme decorated NPs penetrating a mucus layer that would stop conventional NPs.

Figure 1: Possible scenarios of mucus interactions with particles of different surface chemistries

The effect of these NPs on the mobility of intestinal mucin gel was assessed by pulse-gradient-spin-echo NMR (PGSE-NMR); whereas the potential of the NPs to interact with the mucus and alter its tridimensional structure was investigated using two scattering techniques, small angle neutron scattering (SANS) and spin-echo SANS (SESANS).

The proteolytic strategy showed promising results, i.e. insertion of 0.5wt% of enzyme functionalized NPs to 5wt% intestinal mucin solution led to c.a. 2 fold increase in the mobility of the mucin molecules as measured by PGSE-NMR, this is indicative of a significant change in the structure of the mucin.

Scattering measurements also revealed a change in the mucus structure upon addition of functionalized NPs, occurring mostly at a lengthscale larger than 0.5μm.

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O-F4-05-01

ELECTROCHEMICAL BIOSENSOR BASED ON TYROSINASE MODIFIED BORON DOPED DIAMOND ELECTRODES FOR THE DETECTION OF BI-

SPHENOL A

Nedjla Zehani (a, b), Philippe Fortgang (a), Carole Chaix (a), Rochdi Kherrat (b), Nicole Jaffrezic-Renault (a)

a Université Claude Bernard-Lyon 1, Institut des Sciences Analy-tiques, UMR 5280, 5 rue de la Doua, Villeurbanne 69100, France

b University of Annaba, Faculty of Engineering Sciences, Laboratory of Environmental Engineering, B.P.12, Annaba ,23000 Algeria

* Corresponding author: [email protected]

To date, a great endocrinological concern about endocrine disrupting compounds, such as bisphenol A has largely arisen, because it is released into our environment from many kinds of the poly-car-bonate plastics, epoxy resins of food cans, etc, which is able to mimic the body ‘s own hormones and lead to negative health effects [1]. Enzymatic biosensor could be useful for label-free electrochemical monitoring of bisphenol A, that’s why, much effort has been devoted to the design of functional elec-trode surfaces for immobilization of enzyme molecules for sensitive electrochemical applications, in particular, there has been a great interest in the study of enzymatic boron doped diamond film elec-trodes (BDD) because they possess many proprieties such as the high electrochemical stability, wide electrochemical potential window and biocompatible [2]. In this study, a new biosensor based on im-mobilized tyrosinase onto boron doped diamond electrodes (BDD) is presented. Firstly, the surfaces of BDD were functionalized in situ through covalent grafting of diazonium salt, then, multi walled carbon nanotube (MWCNT) which widely used in the fabrication of electrochemical biosensor due to their excellent electro activity was dispersed into the enzymatic solution and tyrosinase was immobilized by cross-linking using glutaraldehyde as cross- linker. The electrochemical detection is performed us-ing Cyclic Voltammetry techniques, the intensity of the reduction peak is proportional to logarithm of the concentration of the target molecules and very low detection limits were reached as well as a high selectivity in real samples.

References

[1] Aminur Rahman. MD, Shiddiky. M.J, Park. J.S, Shim.Y.B, Biosens. Bioelectron , 22, 2464-2470. (2007) [2] Lee.J, Park. S.M, Anal.Chim.Acta , 545, 27-32 (2005)

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O-F4-05-02

Simultaneous and rapid asphaltene and TAN determination for heavy petroleum using an H-cell

Oluwarotimi O. Alabi, Stephen A. Bowden, John Parnell

Dept Geology and Petroleum Geology, University of Aberdeen, Aberdeen, AB24 3UE

Abstract

Characterising the asphaltene and carboxylic acid (naphthenic acid) content of crude oil is important for petroleum production, transport, storage and environmental science. This is because, the propor-tion of asphaltene and the concentration of acidic compounds in petroleum can be used to characterise viscosity (e.g. producibility), refining potential (e.g. its value) and chemical recalcitrance and thus be-haviour as a contaminant. Here we present an assay for determining the proportion of asphaltene and total acid number (TAN) of petroleum. The method utilises a microfluidic component called an H-cell and produces an asphaltene-free fraction, either hydrocarbon or methanol-soluble, that can be forward-ed for further advanced analysis and used to determine asphaltene content and TAN value. The H-cell method depends on a diffusion-based separation that is only practical when a sample is manipulated at a microscale and thus is fundamentally different to previous methods for assaying these parameters that utilise solubility- or chromatography-based methods. Comparisons of asphaltene and TAN mea-surements derived from the H-cell based assay have very high correlations with the ASTM D4124 and ASTM D974-97 methods. Therefore rapid and simultaneous determination of asphaltene content and TAN value can be achieved by an H-cell based format. While this format is suited to miniaturisation and point of need analysis, the main benefit of the H-cell method might be its capacity to provide new analytical windows.

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O-F4-05-03

ANALYSIS OF PHARMACEUTICALS IN ENVIRONMENTAL AQUEOUS SAMPLES: WHEN AND HOW TO PURIFY BEFORE ON-LINE SPE-

UHPLC-MS/MS ANALYSIS

M. Bourdat-Deschamps1, S. Leang1, N. Bernet1, V. Etievant1, S. Nélieu2

1INRA-AgroParisTech, UMR 1091 EGC, 78850, Thiverval-Grignon, France2INRA, UR 251 Pessac, 78026, Versailles, FrancePresenting author: [email protected]

Pharmaceutical products excreted by treated animals or humans are transferred to manure or wastewater, respectively. In wastewater treatment plants, they can be degraded and/or adsorbed into sludge. Therefore pharmaceuticals may be indirectly disseminated into the environment from the recycling of organic residues in agriculture, which is largely encouraged nowadays. Even though the European regulations on this usage do not include pharmaceuticals, they are considered as emerging pollutants due to their potential activity against non-target organisms and their potential risk of transfer towards aquatic ecosystems. It is thus necessary to estimate their available concentration, mostly present in soil water or in the aqueous phase of organic residues. These analyses represent a challenge, because of the trace-level concentration of pharmaceuticals in complex matrices.

We developed an analytical method for the quantification of 14 pharmaceuticals (including 8 antibiotics) in various aqueous environmental samples: soil water and aqueous fractions of pig slurry, digested pig slurry and sewage sludge, which present a wide range of dissolved organic carbon (DOC) content [1]. The analysis was performed by online solid-phase extraction coupled to ultra-high performance liquid chromatography with tandem mass spectrometry (on-line SPE-UHPLC-MS/MS). During this development, we have been particularly confronted to the importance of matrix effects in mass spectrometry analysis. Indeed, undesirable molecules present in the samples can strongly modify the MS signal of the analytes, leading to a wrong quantification and an increase of quantitation limits. We thus proposed a criterion and methods to deal with these matrix effects.

The matrix effects, mostly due to ion suppression, were shown to be a function of the DOC content and its origin. They were limited in soil water which presents low DOC content (-22% to +20%), thus internal quantification by isotopic dilution allowed their correction. On the contrary, in charged matrix they could rise up to the [-38% to -93%] range. The matrix effects variability between the samples suggested DOC content cut-offs above which sample purification was required. These cut-offs depended on compounds, with concentrations ranging from 30-290 mg C/L for antibiotics up to 600-6400 mg C/L for the most apolar compounds. When necessary, a purification method compatible with fluoroquinolones and tetracyclines was furthermore proposed. It was based on a modified QuEChERS (Quick, Easy, Cheap, Effective, Rugged and Safe) extraction procedure using a new composition of salts. The overall procedure was found simple, rapid, sensitive, accurate and efficient.

References1. M. Bourdat-Deschamps, S. Leang, N. Bernet, J.J. Daudin, S. Nélieu, J. Chromatogr. A (2014) in

press, DOI 10.1016/j.chroma.2014.05.006.

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PM-C4-01-01

COMPLEX CRYSTAL STRUCTURE AND ELECTRONIC PROPERTIES OF Ba3MoNbO8.5: A NEW IONIC CONDUCTOR?

Sacha Fop1, Janet M. S. Skakle1, Abbie C. McLaughlin1.1Chemistry Department, University of Aberdeen, AB24 3UE, UK


Ba3MoNbO8.5 is a perovskite derivative that possesses an oxygen stoichiometry directly between that of the palmierite (O8) and the 9R-polytype (O9), causing a mixed distribution of Mo/NbO4 tetrahedra and Mo/NbO6 octahedra in the system [1]. In the present work, Rietveld refinement of neutron powder diffraction data allowed to propose a hybrid structural model formed by the superimposition of three sub-structural units that are capable of representing the average structure of the entire system. Refine-ment also showed the presence of disorder in the oxygen sub-lattice, which could indicate the ability of the structure to support ionic conductivity, as it was confirmed by impedance spectroscopy experi-ments. The latter in fact clearly showed a Warburg response, highlighting a diffusion process occurring at the interface between the electrolyte and the electrodes, and an overall conductivity of Ba3MoNbO8.5 comparable with some leading ionic conductors. Future work will aim to quantify the amount of ionic/electronic conductivity and to investigate the influence of substitutions on the structural and electrical properties of the system.

COMPLEX CRYSTAL STRUCTURE AND ELECTRONIC PROPERTIES OF

Ba3MoNbO8.5: A NEW IONIC CONDUCTOR?

Sacha Fop1, Janet M. S. Skakle1, Abbie C. McLaughlin1.

1Chemistry Department, University of Aberdeen, AB24 3UE, UK Presenting author: [email protected]

Ba3MoNbO8.5 is a perovskite derivative that possesses an oxygen stoichiometry directly between that of the palmierite (O8) and the 9R-polytype (O9), causing a mixed distribution of Mo/NbO4 tetrahedra and Mo/NbO6 octahedra in the system [1]. In the present work, Rietveld refinement of neutron powder diffraction data allowed to propose a hybrid structural model formed by the superimposition of three sub-structural units that are capable of representing the average structure of the entire system. Refinement also showed the presence of disorder in the oxygen sub-lattice, which could indicate the ability of the structure to support ionic conductivity, as it was confirmed by impedance spectroscopy experiments. The latter in fact clearly showed a Warburg response, highlighting a diffusion process occurring at the interface between the electrolyte and the electrodes, and an overall conductivity of Ba3MoNbO8.5 comparable with some leading ionic conductors. Future work will aim to quantify the amount of ionic/electronic conductivity and to investigate the influence of substitutions on the structural and electrical properties of the system.

Figure 1: Arrhenius plot of the conductivity and structural model of Ba3MoNbO8.5. References 1. E. García-González, M. Parras and J. M. González-Calbet, Chem. Mater., 10, 1576 (1998).

Figure 1: Arrhenius plot of the conductivity and structural model of Ba3MoNbO8.5.

References

1. E. García-González, M. Parras and J. M. González-Calbet, Chem. Mater., 10, 1576 (1998).

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PM-C4-01-02

Advanced Graphitic Carbon Nitride Materials for Energy Conversion and Stor-age: Multi-functional Catalysts from Oxygen Reduction to Hydrogen Evolution

K. Qiu1, D. Martin2, S. Shevlin1, C. Xu1, J. Tang2, Z. X. Guo1

1Department of Chemistry, UCL, 20 Gordon Street, London, WC1H 0AJ, UK2Department of Chemical Engineering, UCL, Torrington Place, London, WC1E 7JE, UK

[email protected] or [email protected]

Graphitic carbon nitride (GCN), stacked two dimensional heptazine sheets connected by tertiary amines, is a medium-bandgap semiconductor (ca. 2.7 eV) and therefore a potential photocatalyst for hydrogen evolution reaction (HER). It is also one of the promising metal-free electrocatalysts for oxygen reduc-tion reaction (ORR) due to its relatively high nitrogen content [1]. In addition, GCN features facile syn-thesis from polymerization of low-cost melamine/urea, controllable structure and morphology design and high thermal and chemical stability, which make the mass production of GCN materials potentially feasible [2]. Herein, we present that versatile GCN based materials can act as multifunctional catalysts from ORR for fuel cells and metal-air batteries to HER via visible light driven water splitting.

In terms of ORR, intercalation of graphene sheets (GS) into GCN layers can significantly increase its electrical conductivity and thus improve the catalytic activity. We have further demonstrated that GS/GCN composites can either be used as excellent metal-free catalysts itself if the original layered mor-phology is turned into hierarchically porous via addition of excess silica nanosphere suspension [3]; or alternatively it can be applied as supporting materials for non-precious metal co-catalysts (i.e. Fe or Co based), which displays reduced overpotential and fast reduction kinetics due to the strong interaction between metal and GS/GCN composites. As for HER, the bandgap of GCN can be engineered by in-troducing certain amount of GS. Three-dimensional composites are obtained through the hydrothermal treatment of exfoliated GCN and GS, which show enhanced surface area providing abundant reactive sites for HER. What’s more, even the bulk GCN is able to show ultrahigh hydrogen evolution rate if the synthesis approach is delicately optimised. It is illustrated that polymerisation status and surface proton concentration are also critical to hydrogen production, besides the commonly known effects of surface area and bandgap [4].

Figure 1: Schematic illustration of multi-functional graphitic carbon nitride based materials.

References1. Y. Zheng, J. Liu, J.Liang, M. Jaroniec and S. Qiao, Energy Environ. Sci. 5, 6717 (2012).

2. Y. Wang, X. Wang, and M. Antonietti, Angew. Chem. Int. Ed. 51, 68 (2012).3. K. Qiu and Z. X. Guo, J. Mater. Chem. A 2, 3209 (2014).4. D. Martin, K. Qiu, S. Shevlin, Z. X. Guo and J. Tang, Angewandte. Chem. Int. Ed. (2014). (under review)

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PM-C4-01-03

DOPING AND DEFECTS IN ZNO NANORODS

D.Parker1, K. Bradley1, D. Cherns 2, D.J. Fermín1.1School of Chemistry,University of Bristol, Bristol, UK

2School of Physics,University of Bristol, Bristol, UKPresenting author: [email protected]

ZnO nanostructures have been widely investigated as an alternative to TiO2 as a mesoporous, wide-band gap photoanode for use in dye-sensitized solar cells or other excitonic devices. Despite beneficial properties, such rapid electron transport and the ability to sustain a depletion layer, facilitating charge separation, the performance of ZnO based cells has so far been found to be inferior to those utilising TiO2[1].This has motivated this study into charge transport behaviour in hydrothermally grown ZnO nanorods[2].From photocurrent studies on as-grown ZnO nanorods, it is possible to identify a distribution of trap states centred at about 1V below the conduction band edge. These result in a slow photo-transient response time at positive applied potentials as the traps are filled on time scales of the order of 100 ms. Annealing in air at 350°C significantly reduces the density of traps. Photoluminesence studies carried out on these materials show that these trap states are also likely to be at least partially responsible for the “green luminescence” often observed in ZnO nanostructures, widely attributed to surface states [3]. Using a modified form of Mott-Schottky analysis to account for radial depletion layers[4], nanorods annealed at 350°C were found to have doping densities of the order of 1018 cm-3, implying the existence of a depletion layer approximately 10nm thick at zero bias.

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Figure 1: The effects of annealing on photoluminescence from ZnO defect states.

References1.J.A. Anta, E. Guillén, and R. Tena-Zaera. J. Phys Chem C, 116(21), 11413(2012)2.L.Vayssieres. Adv. Materials,. 15(5), 464 (2003)3.A.B. Djurišić et al. Nanotechnology. 18(9), 095702(2007)4.I.N. Mora-Seró et al. App. Phys. Lett. 89(20), 203117(2006)

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PM-C4-01-04

Production of Dimethyl Ether from Methanol over Nickel modified alumina Ahmed I. Osmana, b, David W. Rooneyb, Jillian Thompsonb, Jehad K. Abu-Dahriehb, Samih A. Halawya,

Mohamed A. Mohameda.aChemistry Department, Faculty of Science - Qena, South Valley University, Qena 83523 – Egypt.

b CenTACat, Queen’s University Belfast, Belfast BT9 5AG, Northern Ireland, UK

Abstract

Dimethyl ether (DME) is amongst one of the most promising alternative, renewable and clean fuels be-ing considered as a future energy carrier. The effect of loading of copper on the catalytic performance of different alumina support during the dehydration of methanol to dimethyl ether (DME) was performed in a fixed bed reactor. There are two level of loading (5, 10 and 15% Ni wt/wt) on both on AC550 ( alu-mina catalyst calcined at 550), to study the effect of loading and the effect of the support during meth-anol dehydration to DME (MTD). The catalysts were characterized by TGA, XRD, BET, TPD-NH3, TEM and DRIFT-Pyridine. Under reaction conditions where the temperature ranged from 180-300 ˚C with a WHSV= 12.1 h-1. In this study the optimum catalyst was 10% Ni/AC550. This catalyst showed a high degree of stability, had one half activity of the pure catalyst (AC550). So we recommended 10% Ni/AC550 for the production of DME from methanol in industry.

Keywords :

Alumina, Characterization, Dimethyl ether, Methanol dehydration, Nanocomposite Catalysts, Bio-fuel.

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PM-C4-01-05

Electronic Structure and Oxide Diffusion in p-doped SrTiO3: a First-Principles Study

Leonardo Triggiani1,2, Ana B. Muñoz-García1, Michele Pavone1.1Dipartimento di Scienze Chimiche, Università di Napoli “Federico II”, Comp. Univ. Monte

Sant’Angelo - Via Cintia 21, 80126, Naples, Italy2Dipartimento di Chimica, Università di Bari “Aldo Moro”, Via Orabona 4, 70125, Bari, Italy


Perovskite-type mixed oxides of general formula ABO3 are ceramic materials widely employed in heterogeneous catalysis and in solid oxide fuel cells [1], Their ability to accommodate different dopants at A and/or B sites enables a tailored tuning of their properties and performances. For example, doped strontium titanate (STO) has been recently proposed as alternative to Ni-based cermets for solid-oxide fuel cell anodes [2].

While most of the works on STO concern with B-site doping [3], here we focus on aliovalent A-site p-doping of STO. In particular, we address the substitution of Sr2+ with the K+ ion and we study how this affects the electronic structure, the oxygen vacancy formation and the oxide diffusion of STO. Hence, oxides with formulae Sr(1-x)K(x)TiO(3-δ) have been investigated with state-of-the-art DFT-based approaches. Our results show that p-doping eases oxygen vacancy formation in STO. Detailed analyses of electronic features allow us to dissect the structure-property relationships at the origin of such behavior. Our insights can contribute to the rational design of new active STO-based materials for energy conversion technologies.

References

1. (a) J. W. Fergus, Solid State Ionics 177, 1529 (2006); (b) M. Gazda, et al., Solid State Phenom. 183, 65 (2011).

2. (a) S. J. Jiang, Mater. Sci. 43, 6799 (2008); (b) C. Sun and U. Stimming, J. Power Sources 171, 247 (2007).

3. (a) S. Carlotto, et al., Chem. Phys. Lett. 588, 102 (2013); (b) J. J. Kim, et al., Solid State Ionics 230, 2 (2013); (c) A. Rothschild, et al., Chem. Mater. 18, 3651 (2006).

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PM-C4-01-06

Efficient direct oxygen reduction by laccases attached and oriented on functionalized carbon nanotubes

Noémie Lalaoui, Mariem Bourourou, Kamal Elouarzaki, Charles Agnès, Alan Le Goff, Michael Holzinger and Serge Cosnier.

Univ Grenoble 1, CNRS, Departement de Chimie Moleculaire, UMR-5250, ICMG FR-2607, BP-53, 38041 Grenoble Cedex 9

[email protected]

Carbon nanotubes (CNTs) have been particularly employed as enzymatic biofuel cell electrodes. CNTs combine a high specific surface for immobilizing a high amount of enzymes with the ability to efficiently wire enzymes. Biocathodes mainly rely on two types of “blue” multi-copper oxidases, laccase and bilirubin oxidase, to reduce oxygen to water. Laccase from Trametes versicolor has the advantage of reducing oxygen at low overpotential provided that an efficient direct electron transfer (DET) is achieved. To immobilize and orient laccase on electrodes, we took advantage of the hydrophobic pocket closed to the T1 multi copper center, which is involved in DET.[1] We have been developed new bioelectrodes based on non-covalent functionalization of multi-walled carbon nanotubes (MWCNTs) by various hydrophobic groups such as anthraquinone,[2] pyrene[3] or adamantane. These groups interact by supramolecular interactions with the hydrophobic pocket of laccase, leading to the orientation and immobilization of the enzyme on the electrode surface. Thanks to this strategy, efficient bioelectrocatalytic properties and improved biocathode stability were achieved. This work constitutes a promising approach for biocathode design in enzymatic biofuel cells.

0.0 0.1 0.2 0.3 0.4 0.5 0.6 0.7 0.8

-2.2-2.0-1.8-1.6-1.4-1.2-1.0-0.8-0.6-0.4-0.20.00.20.4

I/ m

A.c

m-2

E/V

Efficient direct oxygen reduction by laccases attached and oriented on functionalized carbon nanotubes

Noémie Lalaoui, Mariem Bourourou, Kamal Elouarzaki, Charles Agnès, Alan Le Goff,

Michael Holzinger and Serge Cosnier.

Univ Grenoble 1, CNRS, Departement de Chimie Moleculaire, UMR-5250, ICMG FR- 2607, BP-53, 38041 Grenoble Cedex 9

[email protected]

Carbon nanotubes (CNTs) have been particularly employed as enzymatic biofuel cell electrodes. CNTs combine a high specific surface for immobilizing a high amount of enzymes with the ability to efficiently wire enzymes. Biocathodes mainly rely on two types of “blue” multi-copper oxidases, laccase and bilirubin oxidase, to reduce oxygen to water. Laccase from Trametes versicolor has the advantage of reducing oxygen at low overpotential provided that an efficient direct electron transfer (DET) is achieved. To immobilize and orient laccase on electrodes, we took advantage of the hydrophobic pocket closed to the T1 multi copper center, which is involved in DET.[1] We have been developed new bioelectrodes based on non-covalent functionalization of multi-walled carbon nanotubes (MWCNTs) by various hydrophobic groups such as anthraquinone,[2] pyrene[3] or adamantane. These groups interact by supramolecular interactions with the hydrophobic pocket of laccase, leading to the orientation and immobilization of the enzyme on the electrode surface. Thanks to this strategy, efficient bioelectrocatalytic properties and improved biocathode stability were achieved. This work constitutes a promising approach for biocathode design in enzymatic biofuel cells.

1. Blandford, C.F.; Heath, R.S. & Armstrong, F.A. Chem.Commun, 2007, 1710. 2. Bourourou, M.; Elouarzaki, K.; Lalaoui, N.; Agnès, C.; Legoff, A.; Holzinger, M.; Maaref, A. & Cosnier, S. Chem. Eur. J. 2013, 19, 9371-9375. 3. Lalaoui, N.; Elouarzaki, K.; Le Goff, A.; Holzinger, M. & Cosnier, S. Chem.Commun 2013, 49, 9281-9283.

O2

H2O

1. Blandford, C.F.; Heath, R.S. & Armstrong, F.A. Chem.Commun, 2007, 1710.2. Bourourou, M.; Elouarzaki, K.; Lalaoui, N.; Agnès, C.; Legoff, A.; Holzinger, M.; Maaref, A. & Cosnier, S. Chem. Eur. J. 2013, 19, 9371-9375.3. Lalaoui, N.; Elouarzaki, K.; Le Goff, A.; Holzinger, M. & Cosnier, S. Chem.Commun 2013, 49, 9281-9283.

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PM-C4-01-07

Graphene as an Effective Support for Nickel Nanoparticles as a Catalyst for Methanol Electro-Oxidation in Alkaline Medium

Effat Jokar, Amir Rahimi, Figen Kadirgan

Department of Chemistry, Faculty of Science and Letters, Istanbul Technical University, 34469 Maslak, Istanbul, Turkey


According to lack of fossil fuel sources and their pollution problems, fuel cells can be good candidate as a proper energy sources. Among the various systems alkaline fuel cells involving the direct electrochemical oxidation of methanol are useful in portable devices and transport applications. Considerable efforts have been directed towards the development of materials capable of performing electrocatalytic oxidation of methanol [1]. Constructing electrodes with high catalytic activity, stability as well as low price has been a challenge.Graphene, a two-dimensional monolayer, has attracted tremendous attention, owing to its exceptional electronic, large specific surface area, thermal and mechanical properties. Recently, graphene is interesting support for growing of nanoparticles of metal oxides and polymers. Synthesis of various composite structure of metal oxide/graphene in energy storage area as electrodes of batteries, supercapacitors and fuel cells have been reported [2]. In this work, graphene surface is decorated by nickel nanoparticles using a simple electro-deposition method. Nickel nanoparticles (NP) are deposited on the surface of glassy carbon electrode (GCE) which was previously treated by reduced graphene oxide (RGO). Time of electro-deposition was optimized to obtain an electrode with high stability and catalytic activity. Methanol oxidation kinetics will be given in the results. Based on the obtained data, graphene has increased the real surface area and activation of Ni NP (Fig1a,1b) in comparison with GCE substrate. Moreover results have shown that graphene presence, decreases activation energy as well as charge transfer resistance for methanol oxidation (Fig1c).

0.0 0.1 0.2 0.3 0.4 0.5 0.6-0.15

-0.10

-0.05

0.00

0.05

0.10

0.15

0.20

Curre

nt (m

A)

Potential ( V vs. SCE)

GCE-GO GCE

-0.1 0.0 0.1 0.2 0.3 0.4 0.5 0.6 0.7 0.8-0.2

0.0

0.2

0.4

0.6

0.8

1.0

1.2

1.4

Curre

nt (m

A)

Potential ( V vs. SCE)

GO-GCE GCE

0 60 120 180 240 300 360 420 480 540 600-10

0102030405060708090

100110

Z'(o

hm)

Z''(ohm)

GCE-GO GCE

Figure1: Cyclic voltammetries of Ni-NP in a) in KOH electrolyte b) in methanol alkaline electrolyte and c) electrochemical impedance spectroscopy of Ni NP on different substrate, GCE and RGO, in methanol alkaline electrolyte.References[1] Eileen Hao Yu , Ulrike Krewer, Keith Scott, Energies ,3,1499 (2010)[2] Jiahua Zhu, Minjiao Chen, Qingliang He, et al., RSC Adv., 3 , 22790 (2013).

a

b c

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PM-D1-01-01

Photo-induced Water-Oxidation by Mn-Substituted Polyoxometalates

R. Al-Oweini1, A. Sartorel1, B. S. Bassil2, U. Kortz2, Marcella Bonchio.1

1ITM-CNR and Dipartimento di Scienze Chimiche, Università di Padova, via Marzolo 1, 35131 Padova, Italy

2Jacobs University, School of Engineering and Science P.O. Box 750561, 28725 Bremen, GermanyPresenting author: [email protected]

The oxygen-evolving complex of photosystem II (PSII) in green-plants, where water-oxidation takes place, is the fundamental element of photosynthesis, where sunlight is transformed into renewable chemical energy [1]. Prior studies led to the discovery of highly effective, molecular, homogenous catalytic systems of noble metals such as Ru or Ir. Nevertheless, their high cost, toxicity, and low abundance are unfavorable for using them as bulk water oxidation catalysts (WOCs) [1]. Hence, switching focus to environmentally benign, thermally stable, oxidatively robust, and redox-active Mn-substituted polyoxometalates (POMs) are of special interest, also due to the nature of the active center of PSII [2]. Along these guidelines being inspired by nature with the principal aim to design new and efficient oxidation systems employing natural O2 as primary oxidant, a novel Mn-substituted POM was tested as artificial photosynthetic WOC, using the RuII(bpy)3

2+ (P) / Na2S2O8 sacrificial cycle,[1] and was found to be active with higher turnover number and frequency than amorphous Mn-based oxides [3].

Figure 1: Artificial Photosynthesis Scheme

References1 . A. Sartorel, M. Bonchio, S. Campagna, F. Scandola, Chem. Soc. Rev. 2013, 42, 2262-2280.2 . Y. Umena, K. Kawakami, J.-R. Shen, N. Kamiya, Nature 2011, 473, 55-60; K. N. Ferreira, T. M. Iverson, K. Maghlaoui, J. Barber, S. Iwata, Science 2004, 303, 1831-1838.3 . M. M. Najafpour, T. Ehrenberg, M. Wiechen, P. Kurz, Angew. Chem. Int. Ed. 2010, 49 2233; E. A. Karlsson, B.-L. Lee, T. Åkermark, E.V. Johnston, M.D. Kärkas, J. Sun, Ö. Hansson, J.-E. Bäckvall, B. Åkermark, Angew. Chem. Int. Ed. 2011, 50, 11715.

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PM-D1-01-02

Reactive Ligands and Cooperative Organometallic Complexes for Small Molecule Activation

Linda S. Jongbloed, Bas de Bruin, Joost N. H. Reek, Jarl Ivar van der Vlugt*

Homogeneous, Bioinspired & Supramolecular Catalysis, van ‘t Hoff Institute for Molecular Sciences, University of Amsterdam, Science Park 904, 1098 XH Amsterdam, the Netherlands

*e-mail: [email protected]

There has been a recent surge in the application of reactive ligands for bond activation and subsequent cooperative catalysis.1 The targeted design of novel, versatile non-innocent ligand architectures is key to address a broadly applicable palet of bond activation processes.2 We recently investigated the chem-istry of tridentate3 and bidentate4 PN(P) ligand systems, capable of reversible dearomatization, with Cu, Ni and Pd,2 with an emphasis on cooperative E-H activation, including C-H bonds.

Reactive Ligands and Cooperative Organometallic Complexes for Small Molecule Activation

Linda S. Jongbloed, Bas de Bruin, Joost N. H. Reek, Jarl Ivar van der Vlugt*

Homogeneous, Bioinspired & Supramolecular Catalysis, van ‘t Hoff Institute for Molecular Sciences, University of Amsterdam, Science Park 904, 1098 XH Amsterdam, the

Netherlands *e-mail: [email protected]

There has been a recent surge in the application of reactive ligands for bond activation

and subsequent cooperative catalysis.1 The targeted design of novel, versatile non-

innocent ligand architectures is key to address a broadly applicable palet of bond

activation processes.2 We recently investigated the chemistry of tridentate3 and bidentate4

PN(P) ligand systems, capable of reversible dearomatization, with Cu, Ni and Pd,2 with an

emphasis on cooperative E-H activation, including C-H bonds.

In this presentation, recent results obtained with a completely new mode of reversible

ligand reactivity based on reversible C-H activation within the coordination sphere of

transition metals is discussed. This novel design strategy has been successfully exploited

for cooperative activation, including bonds and substrates relevant in the context of small

molecule functionalization. Exemplary catalytic dehydrogenation of formic acid3 will be

discussed with Rh (TOF 169 h-1) as well as related CO2 chemistry, including computational

results to support the cooperative pathway proposed for this relevant reaction using

cyclometalated RhI. We will highlight preliminary results on reactivity with other transition

metal complexes bearing the same ligand scaffold, aimed at selective H2 activation and C-

C bond formation.

1 J.I. van der Vlugt, Eur. J. Inorg. Chem. 2012, 363. 2 a) J.I. van der Vlugt, M.A. Siegler, M. A.; Janssen, M.; D. Vogt, A.L. Spek, Organometallics 2009, 28, 7025; b) J.I. van der Vlugt, M. Lutz, E.A. Pidko, D. Vogt, A.L. Spek, Dalton Trans. 2009, 1016; c) J.I. van der Vlugt, E.A. Pidko, R.C. Bauer, Y. Gloaguen, M.K. Rong, M. Lutz, Chem. Eur. J. 2011, 17, 3850; d) S.Y. de Boer, Y. Gloaguen, J.N.H. Reek, M. Lutz, J.I. van der Vlugt, Dalton Trans. 2012, 41, 11276. 3 L.S. Jongbloed, B. de Bruin, J.N.H. Reek, M. Lutz, J.I. van der Vlugt, submitted.

baseN

PtBu2

ML'N

PtBu2

N

PtBu2

ML'H2NS(O)2R

M N

PtBu2

MN(H)S(O)2R

M

H

EH E

M M L"ligand

L' N M NHR

D

D'activation

N

P

CuSR

CuBr

P

NCu

Br

PBr

PtBu2

Cu

1) NaN(SiMe3)2

2) HSR

2 eq

CuBr(SMe2)

tBu2

tBu2tBu2

N

PtBu2

PtBu2

! "#$%&'( %&)*+*&, *#'- . #/+0, /'1*2 340/*'

Organometallic Cooperative Ligands for Small Molecule Activation

Linda S. Jongbloed, Bas de Bruin, Sandra Y. de Boer, Joost N. H. Reek, Jarl Ivar van der Vlugt*

Homogeneous, Bioinspired & Supramolecular Catalysis, van ‘t Hoff Institute for Molecular Sciences, University of Amsterdam, Science Park 904, 1098 XH Amsterdam, the Netherlands

Jarl I var van der Vlugt [email protected] There has been a recent surge in the application of reactive ligands for bond activation and subsequent cooperative catalysis.1 The targeted design of novel, versatile non-innocent ligand architectures is key to address a broadly applicable palet of bond activation processes.2 We recently investigated the chemistry of tridentate3 and bidentate4 PN(P) ligand systems, capable of reversible dearomatization, with Cu, Ni and Pd,2 with an emphasis on cooperative E-H (E = N, C or S) activation.

baseN

PtBu2

ML'N

PtBu2

N

PtBu2

ML'H2NS(O)2R

M N

PtBu2

MN(H)S(O)2R

M

H

EH E

M M L"ligand

L' N M NHR

D

D'activation

N

P

Cu SR

CuBr

P

NCu

Br

PBr

PtBu2

Cu

1) NaN(SiMe3)2

2) HSR

2 eq

CuBr(SMe2)

tBu2

tBu2tBu2

N

PtBu2

PtBu2

In this presentation, recent results obtained with a completely new mode of reversible ligand reactivity based on reversible C-H activation within the coordination sphere of transition metals is discussed. This novel design strategy has been successfully exploited for cooperative activation, including bonds and substrates relevant in the context of small molecule functionalization. Exemplary catalytic dehydrogenation of formic acid3 will be discussed with Rh (TOF 169 h-1) as well as related CO2 chemistry, including computational results to support the cooperative pathway proposed for this relevant reaction using cyclometalated RhI. We will highlight preliminary results on Ni-based reactivity with the same ligand scaffold, aimed at selective H2 activation and consecutive catalysis. The insertion of CO2 into M-alkyl fragments supported by these reactive ligands will be discussed as well.

! This research is funded by the ERC (Starting Grant) and national research school NRSCC. References

* 1) J.I. van der Vlugt, Eur. J. Inorg. Chem. 2012 , 363. * 2) a) J.I. van der Vlugt, M.A. Siegler, M. A.; Janssen, M.; D. Vogt, A.L. Spek, Organometallics

2009 , 28, 7025; b) J.I. van der Vlugt, M. Lutz, E.A. Pidko, D. Vogt, A.L. Spek, Dalton Trans. 2009 , 1016; c) J.I. van der Vlugt, E.A. Pidko, R.C. Bauer, Y. Gloaguen, M.K. Rong, M. Lutz, Chem. Eur. J. 2011 , 17, 3850; d) S.Y. de Boer, Y. Gloaguen, J.N.H. Reek, M. Lutz, J.I. van der Vlugt, Dalton Trans. 2012 , 41, 11276.

* 3) L.S. Jongbloed, M. Lutz, B. de Bruin, J.N.H. Reek, J.I. van der Vlugt, submitted.

NP(tBu)2Rh

CO

3

20 equiv. HCOOH NPh

P(tBu)2RhCO

OO

H6

! 105, 1JRh-P 168 Hz

In this presentation, recent results obtained with a completely new mode of reversible ligand reactivity based on reversible C-H activation within the coordination sphere of transition metals is discussed. This novel design strategy has been successfully exploited for cooperative activation, including bonds and substrates relevant in the context of small molecule functionalization. Exemplary catalytic dehy-drogenation of formic acid3 will be discussed with Rh (TOF 169 h-1) as well as related CO2 chemistry, including computational results to support the cooperative pathway proposed for this relevant reaction using cyclometalated RhI. We will highlight preliminary results on reactivity with other transition metal complexes bearing the same ligand scaffold, aimed at selective H2 activation and C-C bond formation.

1 J.I. van der Vlugt, Eur. J. Inorg. Chem. 2012, 363.2 a) J.I. van der Vlugt, M.A. Siegler, M. A.; Janssen, M.; D. Vogt, A.L. Spek, Organometallics 2009, 28, 7025; b) J.I. van der Vlugt, M. Lutz, E.A. Pidko, D. Vogt, A.L. Spek, Dalton Trans. 2009, 1016; c) J.I. van der Vlugt, E.A. Pidko, R.C. Bauer, Y. Gloaguen, M.K. Rong, M. Lutz, Chem. Eur. J. 2011, 17, 3850; d) S.Y. de Boer, Y. Gloaguen, J.N.H. Reek, M. Lutz, J.I. van der Vlugt, Dalton Trans. 2012, 41, 11276.3 L.S. Jongbloed, B. de Bruin, J.N.H. Reek, M. Lutz, J.I. van der Vlugt, submitted.

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PM-D1-01-03

ROLE OF Pd/CeZrAlOx IN CO2 UTILIZATION FOR OLEFINS PRODUCTION

Ewa Nowicka1, Christian Reece1, David Willock1, Stan Golunski1 and Graham J. Hutchings1

1Cardiff Catalysis Institute, Cardiff University, Cardiff, CF10 3AT, UKPresenting author: [email protected]

Dehydrogenation with the use of O2 for olefins production has been known for many years in chemistry. The presence of O2 may however, lead to process flammability, production of carbon oxides and over-oxidation, resulting in poor process selectivity. This can be overcome by using a safer, milder and readily available oxidant: CO2. Based on the reaction mechanism, metal oxides displaying high oxygen storage capacity (OSC) and ability to dissociate CO2 in low temperatures would be ideal for this process. One of the metal oxides, which possess these properties, is CeO2. Addition of ZrO2 and Al2O3 to CeO2, increase OSC, surface area and catalyst thermal stability.[1] Different methods for catalyst preparation were investigated, including: supercritical CO2, co-precipitation and physical grinding. When investigating the metal loading on Ce-Zr-Al-Ox support for activity in ODP reaction, it was found that catalyst with 7% Pd loading increased the conversion of propane to more than 35% during 0.5 h reaction, as it is shown in Figure 1.



1Cardiff Catalysis Institute, Cardiff University, Cardiff, CF10 3AT, UK Presenting author: [email protected]

Dehydrogenation with the use of O2 for olefins production has been known for many

years in chemistry. The presence of O2 may however, lead to process flammability, production of carbon oxides and over-oxidation, resulting in poor process selectivity. This can be overcome by using a safer, milder and readily available oxidant: CO2. Based on the reaction mechanism, metal oxides displaying high oxygen storage capacity (OSC) and ability to dissociate CO2 in low temperatures would be ideal for this process. One of the metal oxides, which possess these properties, is CeO2. Addition of ZrO2 and Al2O3 to CeO2, increase OSC, surface area and catalyst thermal stability.[1] Different methods for catalyst preparation were investigated, including: supercritical CO2, co-precipitation and physical grinding. When investigating the metal loading on Ce-Zr-Al-Ox support for activity in ODP reaction, it was found that catalyst with 7% Pd loading increased the conversion of propane to more than 35% during 0.5 h reaction, as it is shown in Figure 1.

Figure 1: Conversion of C3H8 in ODP with Ce0.25Zr0.25Al 0.5O1.75: different Pd loading

Studies involving TAP measurements over 5%Pd/Ce0.25Zr0.25Al0.5O1.75 clearly showed CO production from CO2 at temperature higher than 300°C. These findings indicate that CO2 dissociate on the surface of the catalyst yielding highly oxidative O species, maintaining Ce in a highly oxidized state, therefore helping to facilitate the dehydrogenation process. [2]

.

Figure 2: TAP reactor analysis: Mass 28 at RT and 420oC pulsing CO2

References 1. M. Chen, J. Xu, Y. Cao, H.-Y. He, K.-N. Fan and J.-H. Zhuang, Journal of Catalysis, 2010, 272, 101-108. 2. O. Demoulin, M. Navez, J. L. Mugabo and P. Ruiz, Applied Catalysis B: Environmental,

2007, 70, 284-293.

0.0 0.5 1.0 1.5 2.0 2.510

15

20

25

30

35

40

45

C 3H 8 Con

vers

ion (%

)

Time(h)

2.5%Pd 7.5%Pd 5%Pd 10%Pd

Figure 1: Conversion of C3H8 in ODP with Ce0.25Zr0.25Al 0.5O1.75: different Pd loadingStudies involving TAP measurements over 5%Pd/Ce0.25Zr0.25Al0.5O1.75 clearly showed CO production from CO2 at temperature higher than 300°C. These findings indicate that CO2 dissociate on the surface of the catalyst yielding highly oxidative O species, maintaining Ce in a highly oxidized state, therefore helping to facilitate the dehydrogenation process. [2]



1Cardiff Catalysis Institute, Cardiff University, Cardiff, CF10 3AT, UK Presenting author: [email protected]

Dehydrogenation with the use of O2 for olefins production has been known for many

years in chemistry. The presence of O2 may however, lead to process flammability, production of carbon oxides and over-oxidation, resulting in poor process selectivity. This can be overcome by using a safer, milder and readily available oxidant: CO2. Based on the reaction mechanism, metal oxides displaying high oxygen storage capacity (OSC) and ability to dissociate CO2 in low temperatures would be ideal for this process. One of the metal oxides, which possess these properties, is CeO2. Addition of ZrO2 and Al2O3 to CeO2, increase OSC, surface area and catalyst thermal stability.[1] Different methods for catalyst preparation were investigated, including: supercritical CO2, co-precipitation and physical grinding. When investigating the metal loading on Ce-Zr-Al-Ox support for activity in ODP reaction, it was found that catalyst with 7% Pd loading increased the conversion of propane to more than 35% during 0.5 h reaction, as it is shown in Figure 1.

Figure 1: Conversion of C3H8 in ODP with Ce0.25Zr0.25Al 0.5O1.75: different Pd loading

Studies involving TAP measurements over 5%Pd/Ce0.25Zr0.25Al0.5O1.75 clearly showed CO production from CO2 at temperature higher than 300°C. These findings indicate that CO2 dissociate on the surface of the catalyst yielding highly oxidative O species, maintaining Ce in a highly oxidized state, therefore helping to facilitate the dehydrogenation process. [2]

.


References 1. M. Chen, J. Xu, Y. Cao, H.-Y. He, K.-N. Fan and J.-H. Zhuang, Journal of Catalysis, 2010, 272, 101-108. 2. O. Demoulin, M. Navez, J. L. Mugabo and P. Ruiz, Applied Catalysis B: Environmental,

2007, 70, 284-293.

0.0 0.5 1.0 1.5 2.0 2.510

15

20

25

30

35

40

45

C 3H 8 Con

vers

ion (%

)

Time(h)

2.5%Pd 7.5%Pd 5%Pd 10%Pd


References1. M. Chen, J. Xu, Y. Cao, H.-Y. He, K.-N. Fan and J.-H. Zhuang, Journal of Catalysis, 2010, 272, 101-108.2. O. Demoulin, M. Navez, J. L. Mugabo and P. Ruiz, Applied Catalysis B: Environmental, 2007, 70, 284-293.

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PM-D1-01-04

DISILYLATION AND SILABORATION OF ALKYNES CATALYZED BY GOLD NANOPARTICLES

Manolis Stratakis*

Department of Chemistry, University of Crete, 71003 Iraklion, [email protected]

Supported gold nanoparticles exhibit a powerful catalytic activity in several and often unprecedented organic transformations.[1] We have uncovered and present the ability of Au nanoparticles supported on titania (Au/TiO2) to catalyze for the first time the activation of s 1,2-disilanes[2] and silylboranes[3] and their subsequent cis-1,2-addition to alkynes (Figure 1). Such processes are typically catalyzed by Pd(0) and other late transition metal complexes. It is proposed that the reaction proceeds via initial insertion of the s Si-Si or Si-B linkage on gold in accordance to the recent observation[4] that s disilanes undergo oxidative insertion on Au(I) forming Au(III)-disilyl complexes.

Au/TiO2 (1%)

R'

Si Si

yields up to

94%

mainly cis-addition

DCE, 65 oC

Si

R'

Si

Me

RR

Me

RR

Me

R

RMe

R

RAu/TiO2

(1%)DCM, 25

oCregioselectivity 85-99%

typical isolated

yields ~65-80%

B SiMe

MePh

SiB

R

OO

MeMe

Me

Me

MePhMe

O

OMeMe

Me

Me

Figure 1: Stereoselective and regioselective 1,2-disilylation and silaboration of alkynes catalyzed by supported Au nanoparticles.

References1. M. Stratakis and H. Garcia, Chem. Rev., 112, 4469 (2012).2. a) C. Gryparis and M. Stratakis, Chem. Commun., 48, 10751 (2012). b) C. Gryparis, M. Kidonakis

and M. Stratakis, Org. Lett., 15, 6038 (2013).3. C. Gryparis and M. Stratakis, Org. Lett., 16, 1430 (2014).4. M. Joost, P. Gualco, Y. Coppel, K. Miqueu, C. E. Kefalidis, L. Maron, A. Amgoune and D. Bourissou,

Angew. Chem Int. Ed., 53, 747 (2014).

Acknowledgment: The author acknowledges co-funding of this research in part by the European Regional Development Fund of the EU and national funds- Greek Ministry of Education and Religious Affairs, Sport and Culture/GGET – ΕΥDΕ-ΕΤΑΚ, through the Operational Program Competitiveness and Entrepreneurship (OPC II), NSRF 2007-2013, Action “SYNERGASIA 2011” Project: THERA-CAN - No. 11ΣΥΝ_1_485.

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PM-D1-01-05

Palladium / Ruthenium catalyzed isomerizing olefin metathesis

S. Baader1, P. E. Podsiadly1, D. J. Cole-Hamilton2*, L. J. Gooßen.1*

1 Technische Universität Kaiserslautern, Erwin-Schrödinger-Straße Geb. 54, D-67663 Kaiserslautern, Germany

2 EaStCHEM, School of Chemistry, University of St. Andrews, St. Andrews, KY16 9ST, [email protected]

In the isomerizing olefin metathesis process, a bimetallic palladium / ruthenium system efficiently converts fatty acids into industrially useful multi-component blends [1]. Technical quality fatty acids can be employed in isomerizing self-metathesis, ethenolysis, or cross-metathesis reactions, leading to olefin blends of tailored medium chain lengths from renewable resources rather than from crude oil. The mono- and dicarboxylates formed as secondary products create additional value when used as polymer building blocks.

HO

ORm n

isomerizingolef in

metathesis

fatty acids or

fatty esters functionalized

olefin blends

X+

X =

H, CH2COOH

X mHH

n oH

pRO

O

q rRO

O

OR

O

+

+

Figure 1: Isomerizing metathesis of fatty acids and fatty acid esters.

The same process can give access to styrenes when applied to alkenylbenzenes, which may also originate from renewable sources [2]. Initially, the isomerization catalyst generates a mixture of double-bond isomers, which are continuously converted into shorter olefins by ethenolysis, finally leading to the desired styrene.

FGCH2

FG

k

CH2+H2C CH2+

isomerizing ethenolysis

Figure 2: Isomerizing ethenolysis of alkenylbenzenes.

A similar isomerizing metathesis reaction can give access to the tsetse fly attractant 3-propylphenol when applied on Cardanol, a phenol with a long olefin side chain obtained from cashew nutshell liquid [3].

References1. a) L. J. Gooßen, D. M. Ohlmann, M. Dierker, WO 2012143067, 2012; b) D. M. Ohlmann, N.

Tschauder, J. P. Stockis, K. Gooßen, M. Dierker, L. J. Gooßen, J. Am. Chem. Soc. 2012, 134, 13716.2. S. Baader, D. M. Ohlmann, L. J. Gooßen, Chem. Eur. J. 2013, 19, 9807. 3. a) J. Julis, S. A. Bartlett, S. Baader, N. Beresford, E. J. Routledge, C. S. C. Cazin, D. J. Cole-

Hamilton, Green Chem. 2014, 16, 2846; b) S. Baader, P. E. Podsiadly, D. J. Cole-Hamilton, L. J. Gooßen, publication in preparation.

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PM-D1-03-01

STEREOSELECTIVE RHODIUM-CATALYSED [2+2+2] CYCLOADDITION OF LINEAR ALLENE-ENE/YNE-ALLENE SUBSTRATES: REACTIVITY AND

THEORETICAL MECHANISTIC STUDIES

Ò. Torres1, E.Haraburda1, T. Parella2, M. Solà1, A. Pla-Quintana1

1Universitat de Girona (UdG), Facultat de Ciències, 17071 Girona, Spain2 Servei de Ressonància Magnètica Nuclear, Universitat Autònoma de Barcelona (UAB), 08193

Cerdanyola, Barcelona, [email protected]

One of the main goals of modern organic synthesis is to develop new reactions in which the molecular complexity is rapidly increased. The transition-metal-catalysed [2+2+2] cycloaddition reaction of three unsaturated partners,[1] which allows for the formation of three new bonds, is a nice example of such a reaction type. Allenes, characterised by their two perpendicular π bonds, have been recognised as versatile substrates or intermediates in modern organic synthesis,[2] and, due to the high density of unsaturation, have shown particular promise in the development of cycloaddition and cycloisomerisation reactions.[3] Our interest in the construction of topologically new polycyclic structures, prompted us to explore the [2+2+2] cycloaddition reaction of linear allene-ene-allene and allene-yne-allene derivatives. We will describe the synthesis of the substrates, its [2+2+2] cycloaddition reaction to furnish tricyclic diene scaffolds, and the subsequent Diels-Alder reaction efficiently affording pentacyclic compounds.[4]

X

X·

·RhCl(PPh3)3

toluene, 100ºC

XX

where X = NTs or OFigure 1: [2+2+2] cycloaddition of allene-yne/ene-allene substrates.

Mechanisms that account for the observed reactivity have been proposed for [2+2+2] cycloaddition reactions involving allenes but, to the best of our knowledge, a mechanistic study for such a transformation has not been described. Herein we will explain our studies by means of DFT calculations, leading us to propose a mechanism that rationalises the reactivity of allenes in the [2+2+2] cycloaddition reaction.[4]

References1. For selected reviews, see: a) T. Shibata, K. Tsuchikama, Org. Biomol. Chem. 6, 1317 (2008); b) B. R. Galan, T. Rovis, Angew. Chem. 121, 2870 (2009); Angew. Chem. Int. Ed. 2009, 48, 2830; c) K. Tanaka, Chem. Asian J. 4, 508 (2009); d) P. A. Ingles by, P. A. Evans, Chem. Soc. Rev. 39, 2791, (2010); e) G. Dominguez, J. Pérez-Castells, Chem. Soc. Rev. 40, 3430 (2011); f) N. Weding, M. Hapke, Chem. Soc. Rev. 40, 4525 –4538 (2011).2. a) S. Ma, Chem. Rev. 105, 2829 (2005); b) C. Aubert, L. Fensterbak, P. Garcia, M. Malacria, A. Simonneau, Chem. Rev. 111, 1954 (2011).3. F. López, J. L. Mascareñas, Chem. Eur. J. 17, 418 (2011).4. E. Haraburda, Ò. Torres, T. Parella, M. Solà, A. Pla-Quintana, Chem. Eur. J. doi: 10.1002/chem.201304463.

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PM-D1-03-02

HYDROXYLATION OF PHENOLS USING TYROSINASE MODELS

C. Wilfer1, H. Erdmann1, O. Grossmann1, A. Hoffmann1 and S. Herres-Pawlis1

1Ludwig-Maximilians-University, Department of Chemistry, Butenandtstraße 5-13, 81377, Munich, Germany


Tyrosinase is a Type III copper enzyme that is involved in the activation of oxygen in nature. The active site of tyrosinase consists of a (μ-η2:η2-peroxo)dicopper(II) core [1]. It is known for its phenolase and catecholase activity. Due to its phenolase activity tyrosinase plays an important role in the synthesis of melanine, which is a pigment found for example in the skin, hair and feathers of animals and in pigments in plants. It could be shown that activation, as well as transfer of oxygen is possible using bis(pyrazolyl)methane ligands as precursors [2,3].

HYDROXYLATION OF PHENOLS USING TYROSINASE MODELS

C. Wilfer1, H. Erdmann1, O. Grossmann1, A. Hoffmann1 and S. Herres-Pawlis1

1Ludwig-Maximilians-University, Department of Chemistry, Butenandtstraße 5-13, 81377,

Munich, Germany Presenting author: [email protected]

Tyrosinase is a Type III copper enzyme that is involved in the activation of oxygen in nature. The active site of tyrosinase consists of a (μ-η2:η2-peroxo)dicopper(II) core [1]. It is known for its phenolase and catecholase activity. Due to its phenolase activity tyrosinase plays an important role in the synthesis of melanine, which is a pigment found for example in the skin, hair and feathers of animals and in pigments in plants. It could be shown that activation, as well as transfer of oxygen is possible using bis(pyrazolyl)methane ligands as precursors [2,3].

Figure 1: UV/Vis spectrum of the formation of [{HC(3-tBuPz)2(1-MeIm)}2Cu2O2]2+.

Figure 2: UV/Vis spectrum of the formation of quinoline-7,8-dione.

After treating [HC(3-tBuPz)2(1-MeIm)CuCl] with AgSbF6, the peroxo complex can be generated by reaction of the resulting Cu(I)SbF6 species with O2 at −78°C. The development of the peroxo species was monitored via UV/Vis spectroscopy. The resulting UV/Vis spectrum (Figure 1) displays two bands. The band at 334 nm shows the characteristic in-plane πσ*dxy LMCT-transition, which is indicating formation of a peroxo species. In comparison to other characterized peroxo complexes, the UV-band is blue-shifted by 20 nm. The resulting peroxo species was tested concerning its catalytic properties in the conversion of phenolic substrates (Figure 2). The catalytic conversion of [{HC(3-tBuPz)2 (1-MeIm)}2Cu2O2]2+ with 8-hydroxyquinoline resulted in a remarkable TON of 15. References 1. Y. Matoba, T. Kumagai, A. Yamamoto, H. Yoshitsu, M. Sugiyama, J. Biol. Chem. 281, 8981 (2006). 2. A. Hoffmann, C. Citek, S. Binder, A. Goos, M. Rübhausen, O. Troeppner, I. Ivanović- Burmazović, E. C. Wasinger, T. D. P. Stack, S. Herres-Pawlis, Angew. Chem. Int. Ed. 52, 5398 (2013). 3. A. Hoffmann, S. Herres-Pawlis, Chem. Commun. 50, 403 (2014).

413 nm

After treating [HC(3-tBuPz)2(1-MeIm)CuCl] with AgSbF6, the peroxo complex can be generated by reaction of the resulting Cu(I)SbF6 species with O2 at −78°C. The development of the peroxo species was monitored via UV/Vis spectroscopy. The resulting UV/Vis spectrum (Figure 1) displays two bands. The band at 334 nm shows the characteristic in-plane πσ*dxy LMCT-transition, which is indicating formation of a peroxo species. In comparison to other characterized peroxo complexes, the UV-band is blue-shifted by 20 nm.

The resulting peroxo species was tested concerning its catalytic properties in the con-version of phenolic substrates (Figure 2). The catalytic conversion of [{HC(3-tBuPz)2 (1-MeIm)}2Cu2O2]

2+ with 8-hydroxyquinoline resulted in a remarkable TON of 15.

References1. Y. Matoba, T. Kumagai, A. Yamamoto, H. Yoshitsu, M. Sugiyama, J. Biol. Chem. 281, 8981 (2006).2. A. Hoffmann, C. Citek, S. Binder, A. Goos, M. Rübhausen, O. Troeppner, I. Ivanović- Burmazović, E. C. Wasinger, T. D. P. Stack, S. Herres-Pawlis, Angew. Chem. Int. Ed. 52, 5398 (2013).3. A. Hoffmann, S. Herres-Pawlis, Chem. Commun. 50, 403 (2014).

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PM-D1-03-03

Evidence for an Oxygen Evolving Intermediate in Iron-Catalysed Water Oxidation

Zoel Codolà, 1 Laura Gómez, 1 Scott T. Kleespies, 2 Lawrence Que, Jr,2 Miquel Costas, 1 Julio Lloret-Fillol. 1

1Institut de Química Comptacional i Catalisi, Departament de Química,Universitat de Girona, Campus de Montilivi, 17071, Girona, Spain

2 Department of Chemistry and Center for Metals in Biocatalysis, University of Minnesota, 207 Pleasant St. S.E., Minneapolis, Minnesota 55455, United States


Water oxidation (WO) catalysis constitutes the bottleneck for the development of energy conversion schemes based on sunlight. State of the art of homogeneous WO catalysis is so far efficiently performed with earth-scarce transition metals.[1] Although abundant and less toxic, 3d metal-based complexes are much less established.[2] In this regard, we have discovered that readily available iron coordination complexes are highly efficient homogeneous WO catalysts. TON > 350 and >1000 were obtained when using cerium ammonium nitrate (CAN), and NaIO4, respectively.[3-4] Mechanism investigations on the [Fe(mcp)(OTf)2] WO catalyst reinforced our previously proposed mechanism for Fe-catalyzed WO catalysis. Moreover, a new intermediate has been trapped and characterized by cryospray ionization high resolution mass spectrometry and resonance Raman spectroscopy, which lead to its formulation as [(mcp)FeIV(O)(μ-O)CeIV(NO3)3]

+.[5] We will present herein the the first well-defined inner-sphere complex that mediated WO. The identification of this reactive FeIV–O–CeIV adduct opens new pathways to validates mechanistic notions of an analogous MnV–O–CaII unit in the OEC that is responsible for carrying out the key O–O bond forming step (Figure 1).

OMnIV

O

MnIV

O

MnIV

O

Ca

MnV

O

O

H

O

CeIII

FeV

O

O

H

O

CeIV

FeIV

O

O

H

Lewis acid

Lewis acid

O·

Tyrz

-e

-eelectron aceptor

electronaceptor

Figure 1: Analogy between Fe-catalyzed and Mn-catalyzed water oxidation.

References[1] Codolà, Z., M. S. Cardoso, J., Royo, B., Costas, M., Lloret-Fillol, J. Chem. Eur. J, 19, 7203-7213 (2013).[2] V. Artero and M. Fontecave, Chem. Soc. Rev. 42, 2338 (2013).[3] J. Lloret-Fillol, Z. Codolà, I. Gracia Bosch, L. Gómez, J. Pla, M. Costas, Nat. Chem. 3, 807 (2011).[4] Z. Codolà, I. Gracia B., F. Acuña, J.M. Lluis, M. Costas, J. Lloret F., Chem. Eur.J. 19, 8042 (2013)[5] Z. Codolà, Laura Gómez,1 Scott T. Kleespies, 2 Lawrence Que, Jr,2 Miquel Costas, 1 Julio Lloret-Fillol Nature

Comm. Revisions

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PM-D1-03-04

Photochromic micellar catalysisa convenient tool applied to the Pd-catalysed Tsuji-Trost reaction

M. Billamboz1, F. Mangin1, N. Drillaud1, C. Chevrin-Villette1, E. Banaszak-Léonard1, C. Len1

1 TIMR, EA4297, UTC - ESCOM, 60200, Compiègne, France.Presenting author: [email protected]

According to the green chemistry principles [1] organic chemists are deeply encouraged to carry out reactions in aqueous media. Starting from non-hydrosoluble substrates implies to employ transfer agents such as micelles or aggregates composed of amphiphilic molecules. The use of micellar system in organic synthesis showed that surfactants increase both the yield and the selectivity.[2] Nonetheless, extraction of the hydrophobic products remains a problem. The solution planed is to synthesize photo-switchable surfactants [3] able to form or disrupt micelles or aggregates as many as you want. Among photo-switchable candidates, Azopeg 1 has been successfully used to perform the Pd-catalyzed Tsuji-Trost reaction.[4]

Scheme 1: Equilibrium between cis and trans form of Azopeg 1 applied to organic reactions.

References1. P. T. Anastas, J. C. Warner, Green Chemistry: Theory and Practice, Oxford University Press: New

York, 1998, p.302. (a) T. Dwars, E. Paetzold, G. Oehme, Angew. Chem. Int. Ed. 2005, 44, 7174 ; (b) N. Drillaud, E.

Banaskak-Léonard, I. Pezron, C. Len, J. Org. Chem. 2012, 77, 9553.3. T. Shang, K. A. Smith, T. A. Hatton, Langmuir 2003, 19, 10764.4. M. Billamboz, F. Mangin, N. Drillaud, C. Chevrin-Villette, E. Banaszak-Léonard, C. Len, J. Org.

Chem. 2014, 79, 493.

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PM-D1-03-05

SURFACE STRUCTURE SELECTIVITY IN CATALYTIC HYDROGENATION

Shaoliang Guan1, Gary A. Attard1, Andy J. Wain2

1Cardiff University, CF24 1DR, Cardiff, United Kingdom2National Physical Laboratory, TW11 0LW, Teddington, UK


A novel in-situ surface enhanced Raman spectroscopy (SERS) was used to study the selective hydrogenation of various alkyne molecules on different platinum/palladium single crystal surfaces [1]. The shell-isolated nanoparticles enhanced Raman spectroscopy (SHINERS) offered a brand new fashion of exploring heterogeneous catalytic reactions [2]. For instance, in the Orito reaction [3], the discovery of a new intermediate adsorbed on platinum surface could result in proposing a totally different mechanism [4]. Also, the selective semi-hydrogenation of alkyne can offer high yield of alkene. This powerful technique can make any SERS inactive metal substrates be possible to be detected by SERS using a distribution of gold-silica core-shell nanoparticles on flat metal surfaces (Figure 1). Therefore, any reaction progress and interaction between target molecules and catalyst surfaces with specific structure may be monitored.

Figure 1: Scheme of obtaining enhanced Raman spectra of adsorbed species on metal surfaces

References1. G. A. Attard, S. Guan, et al, Faraday Discussion, 162, 57 (2013). 2. J. F. Li, B. Ren, Z. L. Wang, Z. Q. Tian, et al. Nature Chemistry, 464, 292 (2010).3. Y. Orito, S. Imai, S. J. Niwa, Chem. Soc. Jpn., 8, 1118 (1979).4. S. Guan, G. A. Attard, A. J. Wain, Angewandte Chemie Int., (To be submitted).

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PM-D1-03-06

Tridentate N-Heterocyclic Carbene Titanium(IV) Complexes as new Class of Catalyst for the Copolymerization of Cyclohexene Oxide with Carbone Dioxide

C. C. Quadri1, E. Le Roux.1

1Chemistry Department, University of Bergen, 5007, Bergen, NorwayPresenting author: [email protected]

The synthesis of alternated polycarbonates via metal-catalyzed coupling reactions of CO2 with epoxides has attracted a great attention over the past several decades and is among the most promising processes for CO2 utilization.1 Since the seminal reports of Inoue in 1969 using a mixture of ZnEt2/H2O, a plethora of catalysts based on divalent (Zn, Cd, Mg, Co) and trivalent (Al, Co, Cr, Fe, Mn, Ln) metal centers with a wide variety of ligands (mostly with phenoxide, b-diiminate and salen type ligands) have been studied for various epoxides copolymerizing with CO2.

1 The only examples of active tetravalent metal (Ti, Zr, Ge and Sn) precursors, supported by boxdipy (=1,9-bis(2-oxidophenyl)dipyrrinate)) ligand mimicking the salen-type ligands, were recently investigated by Nozaki and co-workers.2 Inspired by this work, we investigated the potential of a new family of precursors based on the use of bisphenolate mer-tridentate NHC pincer ligand combined with Ti(IV) metal center3 as catalyst component for the copolymerization of cyclohexene oxide (CHO) with CO2 (Fig. 1).4

O

Ox

O

CHO PCHC

O+ CO2

Cat.

Cocat.

N NtBu

tBu tBu

tBu

O OTi

X1L

X2

(3) X1

= Cl,

X2

= OiPr, L

= THF

(1) X1

= X2

= Cl

(2) X1

= X2

= OiPr

Nozaki (2011) This

work

TiNN

ClO O

tBu

tBu tBu

tBu

THF

Ph

Figure 1: Investigation of new tetravalent Ti precursors for the copolymerization of CHO/CO2.

Upon addition of [PPN]X’ salts, all NHC Ti(IV) complexes were found to be active and highly selective toward the formation of PCHC (poly(cyclohexene carbonate)). The influence of different parameters, such as the nature of complexes/cocatalysts, concentrations, temperature and CO2 pressure, on the copolymerization results will be discussed.

References1. For recent reviews see: a) G. W. Coates, D. R. Moore, Angew. Chem. Int. Ed., 48, 6618 (2004); b)

M. R. Kember, C. K. Williams, Chem. Commun. 47, 141 (2011); c) S. Klaus, M. W. Lehenmeier, C. E. Anderson, B. Rieger, Coord. Chem. Rev. 255, 1460 (2011); d) D. J. Darensbourg, S. J. Wilson, Green Chem. 14, 2665 (2012).

2. K. Nakano, K. Kobayashi, K. Nozaki, J. Am. Chem. Soc. 133, 10720 (2011).3. C. Romain, L. Brelot, S. Bellemin-Laponnaz, S. Dagorne, Organometallics 29, 1191 (2010).4. C. C. Quadri, E. Le Roux, Dalton Trans. 43, 4242 (2014).

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PM-D1-04-01

Stability and performance of a FeCeAg catalyst for the Reverse Water Gas Shift (RWGS) reaction

R. Znaiguia1, M. Tabarant2, L. Bedel3, J.M. Borgard1

1 DEN/DANS/DPC/SCCME//LM2T CEA Saclay, 91191, Gif sur Yvette, France2 DEN/DANS/DPC/SEARS/LISL CEA Saclay, 91191, Gif sur Yvette, France

3 DRT/LITEN/DTBH/SCTR/LER CEA Grenoble, 38000, Grenoble, FrancePresenting author: [email protected]

Environmental problems due to the emission of greenhouse gases such as carbon dioxide (CO2) and methane (CH4) have become a major global problem that should be solved. A promising way to valorise CO2 is to hydrogenate it into syngas using the RWGS reaction to build up fuel for transportation [1]. The RWGS is a moderately endothermic reaction and can be described by the following equation.

CO2 +H2 → CO + H2O ΔH298K = 41.19kJ.mol-1

Many studies have examined the use of the Fe catalyst in WGS (Water Gas Shift reaction) and RWGS [2]. In our case we synthesized and tested unsupported and supported Fe catalysts on alumina and doped with Ce and Ag.

0

10

20

30

0 50 100 150 200 250 300

CO

pro

duct

ivity

(mm

ol C

O.h

-1.g

-1)

Time (min)

FeCeAg FeCeAg/Al2O3 Fe-com

0

10

20

30

40

0 50 100 150 200 250 300

Cata

lytic

act

ivity

(mm

ol C

O2.

h-1.

g-1)

Time (min)

FeCeAg FeCeAg/Al2O3 Fe-com

Figure 1: Catalytic performances of different Fe based catalysts for the CO2 conversion at 723 K

As shown in figure 1, FeCeAg/Al2O3 catalyst exhibited higher activity and CO productivity than the commercial iron (Fe-com) catalyst.

Different preparation parameters such as the maturation time, the amounts of iron and silver precursors, calcination temperature are studied in order to determine their influences on the catalyst activity. These good performances can be explained by the better distribution of active sites on the support and the large surface area and pore size delaying the catalyst deactivation by carbon formation on its surface.

Further studies are planned to improve the catalyst stability and productivity.

References1. P. Vibahtavata, J.M. Borgard, M. Tabarant, D. Bianchi, C. Mansilla, Int. J. Hyd. En. 38 (2013) 6397-

6405.2. S.S. Kim, H.H. Lee, S.C. Hong, App. Cat.A: Gen., 423–424 (2012) 100–107

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PM-D1-04-02

CATALYTIC CONVERSION OF UNACTIVATED NITRILES INTO N-SUBSTITUTED AMIDES

A. Simge Davulcu1, Jonathan MJ Williams.2

1Department of Chemistry, University of Bath, BA2 7AY, Bath, UKPresenting author: [email protected]

The amide bond is essential to sustain life, making up the peptide bonds in proteins such as enzymes. It is also found in numerous natural products and biologically active molecules (Figure 1). Despite their importance, no currently used industrial methods for constructing the amide bond are particularly atom–efficient.[1]

HO

HN

O

Paracetamolanalgesic

HN

O

R

N

S

COOH

H

O

Penicillinantibiotic

SNHO

O

Citioloneused

in

liver therapy

Figure 1. Amide bonds in natural products and biologically active molecules

We have developed a zinc triflate and hydroxylamine hydrochloride catalysed methodolgy for direct conversion of unactivated nitriles into N-substituted amides (Figure 2).[2] The reaction proceeds in environmentally friendly water, using non-precious zinc catalyst and provides a straightforward, atom-efficient methodology to synthesise secondary and tertiary amides from nitriles. Catalytic conversion of nitriles into N-substituted amides have only been reported using precious catalysts such as platinum and ruthenium before.[3]

R N + HNR1R2 +

H2O R N

OR2

R1

10 mol%

Zn(OTf)2

10 mol%

NH2OH.HCl

8-24 h, 110-120

°C

Figure 2. Amide synthesis from nitriles and amines in water

The zinc triflate in combination with hydroxylamine hydrochloride salt efficiently catalyses the direct conversion of unactivated nitriles into N-substituted amides with both primary and secondary amines. Possible mechanisms for this reaction are discussed and evidence for initial amidoxime and amidine formation pathways are reported. Isolated yields vary from 25-96%.

References(1) (2) C. L. Allen and J. M. J. Williams, Chemical Society Reviews 2011, 40, 3405-3415.(2) S. Davulcu, C. L. Allen, K. Milne and J. M. J. Williams, ChemCatChem 2013, 5, 435-438.(3) (3)C. J. Cobley, M. van den Heuvel, A. Abbadi and J. G. de Vries , Tetrahedron Letters 2000,

41, 2467-2470.

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PM-D1-04-03

Cu(II) immobilized SBA-15 nanocatalyst for acid-free one-pot synthesis of amides from aldehydes via Beckmann rearrangement in aqueous medium

C. K. P. Neeli1, S. Ganji1, D. R. Burri1, R. R. Kamaraju Seetha.1

1Catalysis Laboratory, Indian institute of Chemical Technology, 500 607, Hyderabad, IndiaPresenting author: [email protected]

Amides are the potential compounds for engineering plastics, intensifiers of perfumes, antiblock reagents, color pigments for inks, detergents, lubricants etc. 1 Development of green catalytic procedures for synthesis of amides from readily available and inexpensive starting materials are utmost important. 2 At this juncture, a novel, versatile, reproducible Cu(II) anchored mesoporous catalyst has been synthesized by a facile method, which effectively catalyzed various aldehydes into amides through Beckmann rearrangement in aqueous medium in one-pot under acid-free conditions. With this catalyst benzaldehyde is completely converted giving 98% selectivity of amide and exhibited same activity in the tested five repeated cycles. Stability of the catalyst both in activity and structure have been confirmed by various characterization techniques such as XRD, N2 adsorption, TEM and XPS.

O

SBA-NN-

NH2OH.HCl, NaoAc, 90 oC, H2O, 5 h

Benzaldehyde

Cu

Conversion = 100% Selectivity = 98%Benzamide

O NH2

References1. C. E. Mabermann, inEncyclopedia of Chemical Technology, ed. J. I. Kroschwitz, John Wiley &

Sons, NewYork, vol.1, pp. 251–266, (1991).2. C. L. Allen and J. M. J. Williams, Chem. Soc. Rev., 40, 3405, (2011).

TEM image pattern of Cu (II) immobilized SBA-15

Wide angle XRD pattern of Cu (II) immobilized SBA-15

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PM-D1-04-04

A BINOMIAL APPROACH TO STOCHASTIC CHEMICAL KINETICS

G. Lente.University of Debrecen, 4032, Debrecen, Hungary


Stochastic chemical kinetics deals with the description of the time dependence of chemical reactions on the level of individual molecules [1]. The stochastic approach is necessary to replace the usual deterministic approach whenever the number of species is low, or special mechanisms amplifying initial fluctuations are operative. Recently, the stochastic approach was successfully used to interpret absolute asymmetric synthesis [2, 3] and its necessity was also demonstrated in enzyme kinetics [4, 5]. Direct stochastic kinetic calculations typically involve great computational. Therefore, analytical approximations are useful in practice. This contribution introduces a new approximation, which will be called ‘binomial approach’.The method is based on Kurtz’s theorem [6], which posits that the stochastic description of a system converges to the deterministic one in the limit of infinite volume. The essence of the binomial approach is that the probabilities of individual states of the system are obtained as a combination of binomial distributions for which the deterministic solution is used as a guiding parameter. The approach will be presented through examples using single step chemical reactions characterized by the following deterministic rate law:

([A])[A] f

dtd

=

Using the solution of this differential equation, [A]t, the individual state probabilities of the stochastic master equation can be approximated as:

[ ] mNm

m tptpmN

tP −−

= 0)(1)()( 0

Here, Pm(t) is the probability that m molecules of species A remain in the system, N0 is the initial molecule number for A, whereas p, the probability that a given species of A remained intact in the reaction, can be obtained directly from the deterministic solution:

0[A][A]tp =

The research was supported by the EU and co-financed by the European Social Fund under the project ENVIKUT (TÁMOP-4.2.2.A-11/1/KONV-2012-0043).

References1. P. Érdi and G. Lente, Stochastic Chemical Kinetics. Theory and (Mostly) Systems Biological Applications (Springer, New York Heidelberg Dordrecht London, 2014).2. É. Dóka and G. Lente, J. Am. Chem. Soc. 133, 17878 (2011).3. B. M. Morneau, J. M. Kubala, C. Barratt, P. M. Schwartz J. Math. Chem. 52, 268 (2014).4. S. C. Kou, B. J. Cherayil, W. Min, B. P. English, S. X. Xie, J. Phys. Chem. B 109, 19068 (2005).5. É. Dóka and G. Lente, J. Chem. Phys. 136, 054111 (2012).6. T. G. Kurtz, J. Chem. Phys. 57, 2976 (1972).

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PM-D1-04-05

BASE FREE GLYCEROL OXIDATION USING TITANIA SUPPORTED TRIMETALLIC CATALYSTS

Gemma L. Brett1,Simon A. Kondrat1, Peter J. Miedziak1, Mark Douthwaite1, Thomas E. Davies1, David J. Morgan1,Jennifer K. Edwards1, David W. Knight1, Christopher J. Kiely1, Stuart H.

Taylor1,and Graham J. Hutchings1

1 Cardiff Catalysis Institute, Cardiff University, Cardiff, CF10 3AT (UK)2 Department of Materials Science and Engineering, Lehigh University, 5 East Packer Avenue,

Bethlehem, PA 18015-3195 (USA) Presenting author: [email protected]

The use of bio-renewable resources, such as glycerol, a by-product from bio-diesel manufacture, can provide a viable way to make value added products using greener technology[1]. Base-free selective oxidation of glycerol has been investigated using trimetallic Au–Pd–Pt nanoparticles supported on titania and their corresponding bimetallic catalysts. Catalysts were prepared by the sol-immobilization method and characterized by means of TEM, UV/Vis spectroscopy, diffuse reflectance infrared fourier transform spectroscopy, X-ray photoelectron spectroscopy, and microwave plasma–atomic emission spectroscopy.

It was found that of the bimetallic catalysts, Pd–Pt/TiO2 was the most active with high selectivity to C3 products[2]. The addition of gold to this catalyst to form the trimetallic Au–Pd–Pt/TiO2, resulted in an increase in activity relative to Pd–Pt/TiO2. The turnover frequency increased from 210 h-1 with the Pd–Pt/TiO2 catalyst to378 h-1 for the trimetallic Au–Pd–Pt/TiO2 catalyst with retention of selectivity towards C3 products.

Figure 1: Figure 1. Time on line of base-free glycerol oxidation with Au–Pd/TiO2: (n),Pd–Pt/TiO2 (▲), Au–Pt/TiO2 (l), and Au–Pd–Pt/TiO2 (t). Conditions; 100 °C, glycerol: metal ratio of 2728, 3 bar O2.

References1. G. W. Huber, A. Corma, Angew. Chem. 2007, 119, 7320 –7338; Angew.Chem. Int. Ed. 2007,

46, 7184 –7201.2. Kondrat, S. A., Miedziak, P. J., Douthwaite, M., Brett, G. L., Davies, T. E., Morgan, D.

J., Edwards, J. K., Knight, D. W., Kiely, C. J., Taylor, S. H. and Hutchings, G. J. (2013), doi: 10.1002/cssc.201300834

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PM-D2-01-01

Synthesis of new Pt(II)-complexes by C-H-bond-activation

F. Hossain1, M. Stickel1, H. A. Mayer.1

1Institute of Inorganic Synthesis, University of Tübingen, 72076 Tübingen, GermanyFarzia Hossain: [email protected]

The C-H bond activation is a fundamental process in the formation of a huge variety of C^N coordinated platinum(II) complexes. Particularly C^N^N and C^N*N^C coordinated Pt(II) complexes are known for their thermodynamic stability and chemical resistance towards oxygen and water.1 Furthermore they have interesting luminescence characteristics in liquid and solid state and applications in catalysis.2,3

The synthesis of N^C*C^N-coordinated platinum(II) complexes via ligands with a bridging quaternary sp3-hybridized carbon atom by C-H-bond-activation are for sterical reasons challenging. Because the potentially tetradentate ligands 1, 2 and 3 possess a free rotating C-C-single bond two N^C pockets are generated on each side arm. For product selectivity it is of importance which of the ortho-C-H bonds is activated first by the platinum precursor. The results of the reaction of the ligands with different platinum-precursors will be discussed.

C C C C

N N

CC C C

S N N S

CC C C

O N N O

N^C*C^N-coordinating Ligands with free rotating C-C single bonds:

1 2 3

R1 R2 R2R1 R2 R2

H H H H H H

R1, R2= sterically demanding groups

H H H H H H

Figure 1: The tetradentate ligands 1, 2 and 3

References1 C.-M. Che, Chem. Commun. (2004), p. 1484–1485.2 Y. Ma, Synthetic Metals A 94 (1998), p. 245–248.3 H. A. Zhong, J. Am. Chem. Soc. A 124 (2002), p. 1378–1399.

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PM-D2-01-02

NOVEL TRIFLUOROMETHYLATED P-STEREOGENIC OXAZOLINE LIGANDS

Rima Drissi1, Antonio Togni1

1Department of Chemistry and Applied Biosciences, Laboratory of Inorganic Chemistry,ETH Zürich, Vladimir-Prelog-Weg 2, Zürich, 8093, Switzerland


Since the advent of chiral oxazoline ligands in asymmetric catalysis, the bidentate P-N ligand containing the phenyloxazoline (PHOX) backbone has been extensively used and has demonstrated its versatility in numerous asymmetric reactions [1].

Using this modular backbone, we sought to combine this exceptional chiral motif with a CF3 group using a trifluoromethylation procedure developed in our group [2], thus introducing an additional stereogenic center, namely at the phosphorus atom. We initially achieved the synthesis of P-trifluoromethylated PHOX ligand 1 in two steps from the aminoalcohol as shown in Figure 1 in good yields.

O

∗N

iPr

Br

CNBr

∗OH

NH2

iPr ZnCl2

PhCl, ∆

35-60%

O

∗N

iPr

P∗

1. nBuLi,

-78°C, Et2O

2. PPh(CF3)2

, Et2O, low T

F3C Ph

1

Figure 1: Synthetic pathway towards P-trifluoromethylated PHOX ligands.

The key step, namely nucleophilic substitution in order to introduce the trifluoromethylated phosphane on the aromatic backbone, was carried out using a bistrifluoromethylated phosphane prepared using our hypervalent iodine CF3-transfer reagent 2 under low temperature conditions (Figure 2) [3].

RP

H

H

OIF3C

O2

RP

CF3

CF3

DBU, DCM, low T

Figure 2: Bistrifluoromethylation of primary phosphanes using a λ3-iodane reagent

This straightforward synthetic pathway allows access to ligands with variation not only at the sidechain, but also at the phosphorus atom, which is particularly attractive as it allows modulation of the steric and electronic properties of the ligand in the last step.

After diastereomer separation, promising results are expected in metal-catalyzed asymmetric transformations using these novel ligands [4].

References1. G. C. Hargaden and P. J. Guiry, Chem. Rev. 2009, 109, 2505–50.2. J. Bürgler, Ph. D. Thesis Nr. 19513, ETH Zürich, 2011, p.83.3. P. Eisenberger, I. Kieltsch, N. Armanino, and A. Togni, Chem. Commun. 2008, 1575–7.4. Z. Hu, Y. Li, K. Liu, and Q. Shen, J. Org. Chem. 2012, 77, 7957–67.

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PM-D2-01-03

The Activation of SF6 and Organic SF5 Derivatives at Rhodium: Conversion of SF6 into H2S

L. Zámostná1, M. Ahrens1, B. Braun1, T. Braun.1*

1Humboldt-Universität zu Berlin, Department of Chemistry, Brook-Taylor-Straße 2, 12489, Berlin, Germany


SF6 is a chemically extremely stable gas. Thus, it is ideally suited for some specific applications, for instance as gaseous dielectric for high voltage power applications. However, SF6 is also identified as one of the most potent greenhouse gases featuring an enormous global warming potential. Because of its vast stability, reports on chemical transformations of SF6 are generally scarce and often involve harsh conditions. SF5 groups in organic derivatives are regarded to be highly chemically inert and studies which report on a reactivity of the SF5 moiety are extremely rare. Compounds which contain a SF5 building block are of increasing importance because of their various applications which involve bioactive compounds, liquid crystals and advanced polymer materials.Herein, we report on the defluorination of SF6 and organic SF5 compounds by S‒F and S‒C bond activation reactions at binuclear rhodium complexes [1]. At [{Rh(μ-H)(dippp)}2] (dippp=1,3-bis(diisopropylphophino)propane) the defluorination at the sulfur atom occurs at mild conditions leading to the fluorido complex [{Rh(μ-F)(dippp)}2] and thiolato-bridged derivatives. A remarkable reduction of SF6 in the presence of HSiEt3 gives exclusively the thiolato complex [Rh2(μ-H)(μ-SSiEt3)(dippp)2], FSiEt3 and H2. A unique nonclassical silane complex was identified as one of the key intermediates [1,2]. [Rh2(μ-H)(μ-SSiEt3)(dippp)2] can be converted into H2S. This transformation paves the way for an unprecedented cyclic process to convert the potent greenhouse gas SF6 into H2S, opens up new opportunities for a degradation of SF6 and possibly its transformation into valuable reagents.

Figure 1: S‒F Activation of SF6 and SF5 organyls at [{Rh(μ-H)(dippp)}2].

References1. L. Zámostná, T. Braun, B. Braun, Angew. Chem. 126, 2783 (2014); Angew. Chem. Int. Ed. 53, 2745

(2014). 2. L. Zámostná, M. Ahrens, T. Braun, J. Fluorine Chem. 155, 132 (2013).

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PM-D2-01-04

Five-coordinate cobalt(II), zinc(II) and cadmium(II) complexes with N,N-di(2-picolyl)cyclohexylmethylamine: Synthesis, structure and application to methyl

methacrylate polymerisation

Hyosun Lee and Yujin Song

Department of Chemistry and Green-Nano Materials Research Center, Kyungpook National University, 1370 Sankyuk-dong, Buk-gu, Daegu-city, 702-701, Republic of Korea


The reaction of [CoCl2·6H2O], [Zn(NO3)2·6H2O], and [CdBr2·4H2O] with N,N-di(2-picolyl)cyclohexylmethylamine (dpcma), in ethanol yields i.e. [(dpcma)CoCl2], [(dpcma)Zn(NO3)2], and [(dpcma)CdBr2] complexes, respectively. The X-ray crystal structures of Co(II), Zn(II) and Cd(II) complexes revealed a five-coordinate geomety involving coordination of the nitrogen atom in cyclohexylmethylamine moiety to the corresponding metal centre. Specifically, [(dpcma)Zn(NO3)2] was distorted square-pyramidal, however, [(dpcma)CdBr2] and [(dpcma)CoCl2] complexes showed distorted trigonal bipyramidal geomety. [(dpcma)CdBr2] showed the highest catalytic activity for the polymerisation of methyl methacrylate (MMA) in the presence of modified methylaluminoxane (MMAO) with an activity of 7.00 × 104 g PMMA/molcat·h at 60°C. The syndiotacticity of poly(methylmethacrylate) (PMMA), characterised using 1H NMR spectroscopy, was ca. 0.70.

Figure 1: The molecular structure of [(dpcma)CoCl2]

References

1. B. Antonioli, B. Buchner, J. K. Clegg, K. Gloe, K. Gloe, L. Gotzke, A. Heine, A. Jager, K. A. Jolliffe, O. Kataeva, V. Kataev, R. Klingeler, T. Krause, L. F. Lindoy, A. Popa, W. Seichtere and M. Wenzela, Dalton Trans. 24, 3503 (1995).

2. J. Zhang, W. Zhang, X. Zhu, Z. Cheng and J. Zhu, J. Polym. Sci. Pol. Chem. 45, 5722 (2007).

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PM-D2-01-05

Molybdenum Dinitrogen Complexes Supported by Tripod Ligands: Tuning the Activation of N2

S. Hinrichsen1 and F. Tuczek1

1Institute of Inorganic Chemistry, Christian-Albrechts-Universität zu Kiel, Max-Eyth-Straße 2, 24118 Kiel, Germany

Presenting author: Svea Hinrichsen, [email protected]

To investigate synthetic nitrogen fixation with molybdenum dinitrogen complexes our working group established “tripod” ligands which are able to saturate the pivotal position trans to N2 avoiding the formation of a [Mo(I)N2XL4] species prone to disproportionation[1-3]. We started our investigations with the ligand 1,1,1-(trisdiphenylphosphinomethyl)ethane (tdppme), which has only arylphosphine moieties[1]. By employing mixed aryl-/alkyl-phosphine donors with neopentyl- or isobutyl-backbones, we figured out that the backbone as well as the substituents of the phosphine groups strongly influence both the structure of the complex and the activation of the N2 ligand[1,2]. By varying the phosphine donor groups, fine tuning of N2 activation is possible: more nucleophilic phosphines lead to higher activation of the N2 ligand. By using silicon-centered tripod ligands, we were able to replace step by step the arylphosphines by the smallest alkylphosphine, dimethylphosphine, which resulted in a great increase in activation (figure 1)[3,4]. As coligands we used bis(diphenylphosphino)-methane (dppm) and bis(dimethylphosphino)methane (dmpm), resulting in the complexes [MoN2SiP3(dmpm)] and [MoN2SiP3(dppm)][3]. If dmpm is used as a coligand, the molybdenum center is surrounded by five PMe2 groups leading to an NN-stretching frequency of 1943 cm-1. The reactivity of the coordinated N2 ligand against Lewis and Brønstedt acids was also investigated.

Figure 1: The activation of the dinitrogen ligand is increased by the number of alkylphosphine donors[4].

References1. J. Krahmer, F. Tuczek, Eur. J. Inorg. Chem. 28, 4377 (2011)2. L. Söncksen, F. Tuczek, Inorg. Chem. 52, 6576 (2013)3. H. Broda, S. Hinrichsen, F. Tuczek, Dalton Trans. 43, 2007 (2014) 4. H. Broda, F. Tuczek, Eur. J. Inorg. Chem., submitted.

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PM-D2-02-01

Reactivity of a Trimethylsilyl-Functionalized Phosphasilene and Phosphinosilylene

N. C. Breit1, T. Szilvázi2, S. Inoue*.1

1 Department of Chemistry, Technische Universität Berlin, Straße des 17. Juni 135, 10623 Berlin, Germany

2 Department of Inorganic and Analytical Chemistry, Budapest University of Technology and Economics, Szent Gellért tér 4, 1111 Budapest, Hungary


Low-valent silicon compounds display a rich chemistry and are versatile building blocks in organic and inorganic synthesis. Functionalized silylenes like phosphinosilylenes attracted the attention of researches due to their interesting properties and reactivities. Phosphasilenes feature a polarized silicon-phosphorus double bond based on the different electronegativities of silicon and phosphorus. Our research focus is on the reactivity of the highly polarized phosphasilene 2 which is available from phosphinosilylene 1 (Figure 1) [1]. Both, 1 and 2, exhibit trimethylsilyl (TMS) groups attached to phosphorus or phosphorus and silicon which are known to be good leaving groups. The significant influence of the TMS groups was confirmed in reactions of phosphasilene 2 with group 10 transition metals affording the dinuclear platinum complex 3 and the bis(silylene) nickel complex 4 (Figure 1) [2]. Moreover, tBuCOCl was utilized to remove a TMS group from 1 and 2 yielding the Si-P=C-O heterocycle 5 in the case of 2 (Figure 1) [3]. This presentation includes calculated details of the reaction mechanisms and electronic properties of selected compounds.

O

tBu Cl

N

NSiPh

tBu

tBu

PTMS

TMSPt

Pt

PPh3

PPh3

Ni(COD)2 N

NSiPh

tBu

tBu

Ni

P

COD

TMS

N

NSi Ph

tBu

tBu

N

NSiPh

tBu

tBu

P

TMS

TMSN

NSiPh

tBu

tBu

P

TMSTMS

N

NSiPh

tBu

tBu

P

O tBu

TMS

(C2H4)Pt(PPh3)2

1 2

3

4

5

Figure 1: Reactivity of phosphasilene 2 with group 10 transition metals and an organic acid chloride.

References

1. S. Inoue, W. Wang, C. Präsang, M. Asay, E. Irran and M. Driess, J. Am. Chem. Soc. 133, 2868 (2011).

2. N. C. Breit, T. Szilvási, T. Suzuki, D. Gallego and S. Inoue, J. Am. Chem. Soc. 135, 17958 (2013).

3. N. C. Breit, T. Szilvási and S. Inoue, Chem. Eur. J., DOI: 10.1002/chem.201402693 (2014).

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PM-D2-02-02

A STRAIGHTFORWARD AND VERSATILE APPROACH TO DNA-BINDING CHIRAL PEPTIDE HELICATES

I. Gamba1, G. Rama1, J.-D. Maréchal2, E. Ortega-Carrasco2, M. E. Vázquez3, M. Vázquez López1

1Departamento de Química Inorgánica and CiQUS, Universidad de Santiago de Compostela, 15782 Santiago de Compostela, Spain

2 Departament de Química. Universitat Autònoma de Barcelona, 08193 Cerdanyola, Spain

3 Departamento de Química Orgánica and CiQUS, Universidad de Santiago de Compostela, 15782 Santiago de Compostela, Spain


Helicates are metallo-supramolecular systems with very interesting DNA-binding properties but whose impact in medicinal chemistry is limited due to certain drawbacks related with the synthetic methods available for their construction, which complicate the access to chiral derivatives and also to the multiple structural variants that are required for the systematic studies involved in the optimization of their biological properties [1]. We developed a novel synthetic methodology for the quantitative preparation of water-stable chiral DNA-binding peptide helicates that allow the easy and fast modification of their structure in order to define conveniently their chemical and functional space. Our approach, which is based in the versatility and flexiblility of solid-phase peptide synthesis (SPPS) methodology and in the biocompatibility and structural control of peptides [2], also allows the easy programmation of the supramolecular chirality of the helicates by appropriate selection of key chiral residues located in the sequence of the peptide ligand precursor, which under thermodynamic control direct the folding of the peptide ligand around the metal centres into a predetermined chiral helical conformation.

A STRAIGHTFORWARD AND VERSATILE APPROACH TO DNA-BINDING

CHIRAL PEPTIDE HELICATES

I. Gamba1, G. Rama1, J.-D. Maréchal2, E. Ortega-Carrasco2, M. E. Vázquez3, M. Vázquez

López1 1Departamento de Química Inorgánica and CiQUS, Universidad de Santiago de Compostela,

15782 Santiago de Compostela, Spain 2 Departament de Química. Universitat Autònoma de Barcelona, 08193 Cerdanyola, Spain

3 Departamento de Química Orgánica and CiQUS, Universidad de Santiago de Compostela, 15782 Santiago de Compostela, Spain


Helicates are metallo-supramolecular systems with very interesting DNA-binding properties but whose impact in medicinal chemistry is limited due to certain drawbacks related with the synthetic methods available for their construction, which complicate the access to chiral derivatives and also to the multiple structural variants that are required for the systematic studies involved in the optimization of their biological properties [1]. We developed a novel synthetic methodology for the quantitative preparation of water-stable chiral DNA-binding peptide helicates that allow the easy and fast modification of their structure in order to define conveniently their chemical and functional space. Our approach, which is based in the versatility and flexiblility of solid-phase peptide synthesis (SPPS) methodology and in the biocompatibility and structural control of peptides [2], also allows the easy programmation of the supramolecular chirality of the helicates by appropriate selection of key chiral residues located in the sequence of the peptide ligand precursor, which under thermodynamic control direct the folding of the peptide ligand around the metal centres into a predetermined chiral helical conformation.

SPPS Fe(II)peptide ligandsLL-H or DD-H

NO

HN

P

(D/L)N

O NH

N

NH

N

CO2H

O

O

NHFmoc

P

(D/L)

Figure 1: Peptde helicates synyhesized by SPPS. Introducing of L-Pro or D-Pro residues in the peptide sequence selects a particular supramolecular chirality in the final helicates (ΛΛ- or ΔΔ-, respectively). References 1. S. E. Howson, A. Bolhuis, V. Brabec, G. J. Clarkson, J. Malina, A. Rodger, P. Scott,

Nature Chem. 4, 31 (2012). 2. a) G. Rama, A. Ardá, J.-D. Maréchal, I. Gamba, H. Ishida, J. Jiménez-Barbero, M. E.

Vázquez, M. Vázquez López, Chem. Eur. J. 18, 7030 (2012); b) I. Gamba, I. al adó, G. Rama, M. ertazzon, M. I. ánchez, V. M. ánchez- edre al, J. Mart nez-Costas, R. F. rissos, . Gámez , J. L. Mascare as, M. Vázquez López, M. E. Vázquez, Chem. Eur. J. 18, 13369 (2013).

Figure 1: Peptde helicates synyhesized by SPPS. Introducing of l-Pro or d-Pro residues in the peptide sequence selects a particular supramolecular chirality in the final helicates (ΛΛ- or ΔΔ-, respectively).

References1. S. E. Howson, A. Bolhuis, V. Brabec, G. J. Clarkson, J. Malina, A. Rodger, P. Scott, Nature Chem.

4, 31 (2012). 2. a) G. Rama, A. Ardá, J.-D. Maréchal, I. Gamba, H. Ishida, J. Jiménez-Barbero, M. E. Vázquez, M.

Vázquez López, Chem. Eur. J. 18, 7030 (2012); b) I. Gamba, I. Salvadó, G. Rama, M. Bertazzon, M. I. Sánchez, V. M. Sánchez-Pedregal, J. Martínez-Costas, R. F. Brissos, P. Gámez , J. L. Mascareñas, M. Vázquez López, M. E. Vázquez, Chem. Eur. J. 18, 13369 (2013).

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PM-D2-02-03

HIGH - VALENT NON - HEME TOSYLIMIDO - IRON (IV) SPECIES IN TACN - BASED N5 - PENTADENTATE LIGANDS

Gerard Sabenya,a Laura Gómez,a Martin Clémancey,b Jean-Marc Latour,b Julio Lloret-Fillol,a Miquel Costas.a

aGrup de Química Bioinorgànica i Supramolecular (QBIS). Institut de Química Computacional i Catàlisi (IQCC) and Departament de Química, Universitat de Girona. Campus Montilivi, E17071,

Girona, Catalonia (Spain) [email protected], [email protected] bDSV/iRTSV/CBM, UMR 5249 CEA-Université Grenoble I-CNRS/Equipe de Physicochimie des Métaux en Biologie, CEA-Grenoble, 17 Rue des Martyrs, 38054 Grenoble Cedex 09 (France)

High valent iron complexes have been postulated as reaction intermediates in challenging oxidation reactions performed by bioinspired oxidation catalysts.[1]

The capacity of non-heme oxo – iron (IV) complexes to transfer the oxo moiety to different substrates has been widely studied[2] and it is well known that they are capable of performing such an interesting and challenging chemistry as the abstraction and hydroxylation of C-H bonds, even those as strong as in cyclohexane.[3] Related interesting compounds are tosylimido – iron (IV) species, which are analogue to oxo – iron (IV) complexes, thus should be capable of isolobal amination reactivity. Despite this fact, these compounds have been scarcely studied. Recent studies reported its potential showing the ability of heme and non - heme tosylimido – iron (IV) compounds to transfer the tosylimido moiety to nucleophilic substrates, such as phosphines or sulphides.[4]

In this work we have prepared and completely characterized two novel non – heme tosylimido-iron (IV) compounds (figure 1) and we have investigated its reactivity towards thioanisole substrates to understand the transfer of the tosylimido moiety to the sulphur atom. A comparative analysis of kinetic parameters has been performed, as well as characterization studies of the reaction products by 1H - NMR.

FeIV

N

N N

N

N

N

N

FeIV

N

N

N

N N

TsTs

[FeIV(NTs)(MePy2tacn)]2+

2+ 2+

[FeIV(NTs)(Me2CHPy2tacn)]2+

Figure 1. Tosylimido – iron (IV) compounds studied in this work. References[1] a) M. Costas, K. Chen, L. Que, Jr., Coord. Chem. Rev. 200-20, 517 (2000); b) L. Que, W. B.

Tolman, Nature. 455, 333 (2008).[2] a) L. Que Jr, Acc. Chem. Res. 40, 493 (2007); b) W. Nam, Acc. Chem. Res. 40, 522 (2007);

b) A. Company, G. Sabenya, M. González-Béjar, L. Gómez, M. Clémancey, G. Blondin, A. J. Jasniewski, M. Puri, W. R. Browne, J.M. Latour, L. Que , Jr., M. Costas, J. Pérez-Prieto, J. Lloret-Fillol, J. Am. Chem. Soc. 136, 4624 (2014).

[3] J. Kaizer, E. J. Klinker, N. Y. Oh, J-U. Rohde, W. J. Song, A. Stubna, J. Kim, E. Münck, W. Nam, L. Que, Jr., J. Am. Chem. Soc. 126, 472 (2004).

[4] (a) A. K. Vardhaman, P. Barman, S. Kumar, C. V. Sastri, D. Kumar, S. P. de Visser, Angew. Chem. Int. Ed. 52, 1 (2013); (b) P. Leeladee, G. N. L. Jameson, M. A. Siegler, D. Kumar, S. P. de Visser, D. P. Goldberg, Inorg Chem. 52, 4668 (2013).

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PM-D2-02-04

Structural study of molecular heterobimetallic galloxanes

Erandi Bernabé-Pablo,1 Mónica Moya-Cabrera1,2

1Centro Conjunto de Investigación en Química Sustentable, UAEM-UNAM, Carr. Toluca-Atlacomulco Km 14.5, 50200,Toluca, Estado de México, México.

2Instituto de Química, Universidad Nacional Autónoma de México, C.U. 04510, México, D.F.Presenting author: [email protected]

The preparation of monomeric group 13 metalloxanes is a synthetic challenge due their tendency to oligomerization. In this line, our research group described a convenient method for the synthesis of the molecular alumoxane [{LAl(OH)}2(μ-O)] (L = CH[CMe(NAr)]2

– (Ar = 2,4,6-Me3-C6H2), starting from [(LAlH)2(μ-O)], and its heterobimetallic derivatives[1,2].

In this work, the synthesis of galloxanes analogous is presented. Thereby, the reaction of b-diketiminate gallium dichloride LGaCl2 (L = CH[CMe(NAr)]2

– (Ar = 2,4,6-Me3-C6H2)(1) under controlled hydrolysis in the presence of 1,3-di-tert-butylimidazol-2-ilydene as a hydrogen chloride acceptor led to the preparation of the molecular galloxane containing two terminal OH groups [{LGa(OH)}2(μ-O)](2). The functional group OH was used in the assembly of the heterobimetallic galloxanes with group 4 metals [{(LGa)2(μ-O)}(μ-O)2{M(NR2)2}] (M = Ti(3), R = Me; M = Zr(4), Hf(5), R = Et)[3].

Figure 1: Molecular structure of 5; hydrogen atoms are omitted for clarity. Thermal ellipsoids are set at 50% probability level.Furthermore, the reactivity of compound 2 was studied with boron and silicon reagents leading to compounds exhibiting different connectivity modes. The reaction of Li[N(SiHMe2)2] with 2 resulted in the formation of [{LGa(H)}2(μ-O)](6) via b-hydrogen elimination and opened the possibility of carrying out chalcogen insertion tests in Ga–H bonds and obtaining functionalized galloxanes with SH groups.

References1. S. González-Gallardo, V. Jancik, R. Cea-Olivares, R. A. Toscano, and M. Moya-Cabrera, Angew. Chem. Int. Ed. 46, 2895 (2007). 2. S. Hidalgo-Bonilla, R. Peyrot, V. Jancik, J. Barroso-Flores, M. Reyes-Lezama, and M. Moya-Cabrera, Eur. J. Inorg. Chem. 2849 (2013).3. E. Bernabé-Pablo, V. Jancik, and M. Moya-Cabrera, Inorg. Chem. 52, 6944 (2013).

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PM-D2-02-05

TUNING OF PHOTOPHYSICAL AND ELECTROCHEMICAL PROPERTIES OF PHOTOACTIVE BUILDING BLOCKS FOR PHOTOCATALYSTS

Katharina Ritter1, Sven Rau1

1Ulm University, 89081, Ulm, Germany Presenting author: [email protected]

The research field of light driven hydrogen production exploded in the last decades due to the need of carbon neutral energy source [1]. The photo catalyst L2RutpphzPdCl2 (whereas L = 4,4’-di-tert.-bu-tyl-2,2’-bipyridine and tpphz = tetrapyrido[3,2-a:2’,3’c:3’’,2’’,- h:2’’’,3’’’-j]phenazine) performs the production of hydrogen out of protons with turnover numbers of 161 [2,3]. This system is well re-searched and it was found that if the initial photoinduced metal-to-ligand charge transfer (MLCT) occurs to the bridging ligand and not to the peripheric bipyridine-ligands the efficiency of the photo catalytic process increases [3]. The proportion of the MLCT to the bridging ligand can be tuned by ap-propriate substitution of all ligands at the Ruthenium complex [4].

NN

NN

N

NRu

2+

N

N N

NPd

Cl

Cl

NN

NN

N

NRu

2+

N

N N

N

RutpphzPd

Ru(tbp)2tpphz

The synthesis of 3,16-di(tert.-butyl-phenyl)-tetrapyridophenazine (tpphz(tbp)2) has been optimized by using a new synthetic route. The synthesis of the good soluble tpphz(tbp)2 opens up a possibility of a direct synthesis of mononuclear Ruthenium complexes.The complexes [L2Ru(tbp)2tpphz]2+ (Ru(tbp)2tpphz), [L2Rutp-phz(tbp)2]

2+ (Rutpphz(tbp)2) and the reference compound [L2Ru(tb-p)2phen]2+ (Ru(tbp)2phen) (where (tbp)2phen = 3,8-Bis(4-tert.-butyl-phenyl)-1,10-phenanthrolin) have been synthesized and characterized. Crystal structures or motives could be received of each complex.Photophysical properties were obtained with the aid of the absorption and emission spectroscopy and redox-potentials were recorded with square wave voltammetry. It seems that the stabilization of the MLCT on the bridging ligand takes place.Further investigations as coordinating the catalytic center to the com-plex and performing the catalysis will show if the substitution influ-ences the catalysis in the intended way.

(Endnotes)1 . a) D. G. Nocera, N. S., PNAS 2006, 103, 15729–15735; b) N. Armaroli, V. Balzani, Angew. Chem. Int. Ed. Engl 2007, 46, 52–66.

2 . S. Rau, B. Schäfer, D. Gleich, E. Anders, M. Rudolph, M. Friedrich, H. Görls, W. Henry, J. G. Vos Angew. Chem. Int. Ed. Engl, 2006, 45, 6215–6218; b)

3 . S. Tschierlei, M. Karnahl, M. Presselt, B. Dietzek, J. Guthmuller, L. González, M. Schmitt, S. Rau, J. Popp, Angew. Chem. Int. Ed. Engl. 2010, 49, 3981–3984.

4 . a) M. Schwalbe, M. Karnahl, S. Tschierlei, U. Uhlemann, M. Schmitt, B. Dietzek, J. Popp, R. Groake, J. Vos, S. Rau, Dalton transactions 2010, 39, 2768-2771; b) M. Karnahl, S. Tschierlei, C. Kuhnt, B. Dietzek, M. Schmitt, J. Popp, M. Schwalbe, S. Krieck, H. Görls, F. W. Heinemann S. Rau, Dalton Trans. 2010, 39, 2359–2370.

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PM-E2-01-01

EVIDENCE FOR A MULTI-SITE CATALYTIC MECHANISM IN THE METALLOENZYME OXALATE DECARBOXYLASE

W. Kellett1, N. Richards.1

1Indiana University Purdue University Indianapolis, 46202, Indianapolis, USA Presenting author: [email protected]

The enzyme Oxalate Decarboxylase (OxDc) has been previously thought to catalyze the Manganese(II) dependent conversion of oxalate into carbon dioxide and formate, but the literature lacks fundamental information on OxDc. The objective of this research is to provide sufficient evidence to form a comprehensive catalytic mechanism for OxDc, and to further describe the two Manganese sites (N- and C-terminal). Specific points of contention include: What is the purpose of each Mn binding site? Do the Mn ions communicate, and if so how? What is the oligomeric state of this enzyme, and for what chemical purpose does this oligomer exist? How does the enzyme use the active site(s) Manganese to catalyze decarboxylation chemistry? Our

approach to these questions includes techniques in classical enzymology, chromatographic separation techniques, ultracentrifugation, inorganic spectroscopy such as Electron Paramagnetic Resonance (EPR) and Magnetic Circular Dichroism

(MCD), introduction of fluorinated amino acids into proteins, 19F-Nuclear Magnetic Resonance, and computational modeling. Our results indicate that OxDc employs local and long-range control mechanisms of both Manganese species (N- and C-terminal) as a function of oligomerization, to mediate high-energy chemical reactions by control of highly reactive radical intermediates. [1] Oxalate Decarboxylase, utilizes not only Mn(II), but the higher oxidation state Mn(III) as well. We have elucidated local and long-range structure-based Manganese control mechanisms in OxDc. Tryptophan residues are specifically important for catalytic and structural control in the enzyme, as evidenced by their role not only in enzyme activity, but also in the maintenance of the biologically relevant hexameric oligomerization of the enzyme. Most strikingly, re-engineering experiments to “activate” the non-catalytic site are successful, and additionally suggest that the electronic properties of the non-catalytic site are important for the wildtype enzyme. Work is ongoing to further elucidate these control mechanisms, specifically the role of the tryptophan and tyrosine networks in the reaction control mechanism of OxDc.

References1. P. Campomanes, W. F. Kellett, et al. JACS 136, 2313 (2014).

Figure 1: Panel A – The structure of the biological hexamer, with a single monomer highlighted in purple. Panel B – The two Manganese binding sites within each monomer.

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PM-E2-01-02

The effect of CaNa2-EDTA on zinc, carbohydrate metabolism and glutamic oxa-lic, glutamic pyruvic aminotransferases (GOT, GPT) and alkaline phosphatase

activities in experimental diabetes

Zine KECHRIDDepartment of Biochemistry, Faculty of Sciences, University of Annaba, PO BOX 12,

EL-Hadjar, Annaba 23000, Annaba, ALGERIA. E-Mail: [email protected]

Abstract: To investigate the effect of CaNa2-EDTA and experimental diabetes (IDDM) on zinc and carbohydrate metabolism and the activities of GOT, GPT and alkaline phosphates. Forty male wealing normal albino (Wistar) rats of 8 weeks of age were fed with a basal diet. Twenty rats (n = 20) were then intraperitoneally injected with alloxan to induce diabetes. Then after one week ten rats from each group (n = 20) were administrated intraperitoneally with CaNa2-EDTA for further three weeks. Body weight gain and food intake were recorded regularly. On day 21 after an over night fasting, animals were killed and blood glucose, serum zinc, femur and pancreatic zinc concentrations, liver glycogen contents, serum glutamic oxalic transaminase (GOT), serum glutamic pyruvic transaminase (GPT) and serum alkaline phosphatase were determined. Diabetic rats given CaNa2-EDTA or not had a low body weight gain, high total food intake (hyperphagia), low liver glycogen contents and low serum and pan-creatic zinc concentrations compared to normal ones. The administration of CaNa2-EDTA significantly altered the body weight gain, food intake and serum zinc concentration of either diabetic or non-dia-betic animals. Both diabetic and non-diabetic rats given CaNa2-EDTA had higher blood glucose than their control counterparts. Liver glycogen was also found to be higher in CaNa2-EDTA non-diabetic rats than their controls. In alloxan diabetes, serum GOT and GPT were significantly increased com-pared to normal rats, while the level of serum alkaline phosphatase was decreased. The administration of CaNa2-EDTA led to increasing of GOT and GPT, and decreasing serum alkaline phosphatase. To conclude, the present study demonstrates that CaNa2-EDTA had an effect on body weight gain, glucose utilization and serum zinc. In addition CaNa2-EDTA has affected the activities of GOT, GPT and alka-line phosphatase. Therefore it was appeared that CaNa2-EDTA resulted in the development of severe diabetes.

Key words: Diabetic rats, Non-diabetic rats, Alloxan, CaNa2-EDTA, GOT, GPT, Alkaline phospha-tase, Glycogen.

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PM-E2-01-03

Synthesis of Some New Pyrazole-based 1,3-Thiazoles and 1,3,4-Thiadiazoles as anticancer agents

Kamal M. Dawood,,1 Taha M. A. Eldebss,1 Heba S. El-Zahabi,2 Mahmoud H. Yousef,1 and Peter Metz3

1 Department of Chemistry, Faculty of Science, University of Cairo, Giza 12613, Egypt 2 Department of Pharmaceutical Chemistry, Faculty of Pharmacy, Al-Azhar University, Cairo 11884,

Egypt 3 Department of Chemistry, Technische Universität Dresden, Bergstr. 66, D-01069 Dresden, Germany

*Corresponding author: E-mail: [email protected]

ABSTRACTN-(4-(Pyrazol-4-yl)thiazol-2-yl)-N´-phenylthiourea derivative 2 was synthesized and then treated with variety of hydrazonoyl chlorides under basic condition at reflux to afford the corresponding 2-(4-(pyrazol-4-yl)thiazol-2-ylimino)-1,3,4-thiadiazole derivatives 6, 10a-e and 17a-e. Reaction of 2 with ethyl chloroacetate and with 3-chloro-2,4-pentanedione gave the thiazolidin-4-one 22 and 1,3-thiazole 25 derivatives, respectively. Condensation of thiazolidin-4-one 22 with aldehydes gave their 5-arylidene derivatives 23a-f. Most of the synthesized compounds were tested for anticancer activity against human hepatocelluar carcinoma HepG2 cell line. Their SAR was studied and variously affected by the electronic factor of electron donating and withdrawing groups. Many of the test compounds showed moderate to high anticancer activity

Keywords: Pyrazole; 1,3-Thiazole; 1,3-Thiazolidin-4-one; 1,3,4-Thiadiazole; Anti-tumor activity.

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PM-E2-03-02

CYTOTOXICITY EFFECTS OF EXTRACTS AND ESSENTIAL OIL OF KAEMPFERIA GALANGA ON C33A CELL LINE

M. N. Omar1, S. M. M. Abdul Rahman2, S. J. Arief Ichwan2 A. M. Zuberdi1

1Kulliyyah of Science, International Islamic University Malaysia, Bandar Indera Mahkota, 25200 Kuantan Pahang Malaysia

2Kulliyyah of Dentistry, International Islamic University Malaysia, Bandar Indera Mahkota, 25200 Kuantan Pahang Malaysia


AbstractBackgroung: Malaysian rainforest plants, particularly from Zingiberaceae family, have been studied extensively due to their pharmaceutical properties including anticancer activities. These include plant species from Alpinia [1], Zingiber and Kaempferia [2]. Besides these species, other plants from Artocarpus, Andrographis, Citrus, Cymbopogon, Plumeria, Garcinia and Musa [3] have been assessed, especially on their biological activities towards their medicinal values. The present study was carried with the objective to screen the anticancer activity of Kaempferia galanga extracts on cervical cancer C33A line.Methods: The cytotoxicity study of K. galanga rhizome extract was carried out. The rhizome extracts were obtained by extraction with ethanol, petroleum ether, ethyl acetate and methanol. Meanwhile, the essential oil was produced by steam distillation method. The cytotoxicity activities were assessed on C33A cell line using three assays; MTT, scratch and out-growth assays. Result: Using MTT assay, the ethyl acetate and ethanol extracts were the most cytotoxic at 1000µg/mL where less than 15% of cells were viable. Although the petroleum ether extract and the essential oil showed similar cytotoxity effect at the concentration of 500 µg/mL, the methanol extract was not cytotoxic even at 1000µg/mL. Meanwhile all extracts were able to inhibit or at least slow down cell growth when tested using the scratch assay. The extracts were not able to stop cell metastasis but did reduce the rate of cell metastasis. Conclusion: From the MTT assay it showed that all the extracts were able to induce cell death except the ethanol extract. However, all the extracts were able to inhibit or at least slow down C33A cell growth at certain concentrations. The extracts of K. galanga has potential as anticancer agents as most of the tests carried out showed positive feedbacks.

References1. H. L. De Pooter, M. N. Omar, B. A. Coolsaet and N. A. Schamp, Phytochemistry, 24, 93 (1995). 2. N. H. M. Hasali, M. N. Omar, A. M. Zuberdi and H. Y. AlFarra, Int. J. Biosci. 3, 148 (2013).3. A. Mahmood, M. N. Omar and N. Ngah, Asian Pac J. Trop. Med. 5, 882-886 (2012).

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PM-F1F2-02-01

Facile development of biosensor with carbon black for electrochemiluminescent analysis of urinary oxalate

Aziz Ur Rehman1, Guobao Xu2 , Saima Anjum1

1, The islamia University of Bahawalpur, Pakistan 2, Changchun institute of applied chemistry, Changchun, China

Presenting Author ; [email protected]

Chemically modified electrodes continue to be a focus in numerous electrochemical applications. We are interested in bulk immobilization of metal on Acetylene Carbon to develop biosensor due to facile preparation of electrode and effortless renewal of electrode surface. The immobilization method can simplify the detection system, save expensive reagents and make ECL sensors regenerable. For clin-ical, therapeutic and diagnostic purposes an accurate determination of metabolites in human body is often necessary. This work addresses the immobilization technique for the development and application of simple, sensitive, and selective ECL method for the determination of trace amounts of oxalate in urine samples. Because electrochemiluminescence devices are attractive tools to quantify biological compounds due to the direct conversion of a biochemical event to a current. The dependence of sensi-tivity on various variables was studied. The detection limit found 2.5×10−9 M (S/N=3) for oxalate was remarkably low. The effect of the presence of various commonly associated species with real sample was also explored. The proposed method was successfully applied for the determination of oxalate in urine sample involving immobilization of metal ions on carbon black without using polymer and resin

New References1. Deiss F, LaFratta C N, Symer M, Blicharz T M, Sojic N, Walt D R. Solar Water Oxidation by Com-

posite Catalyst/r-Fe2O3 Photoanodes. J Am Chem Soc 2009; 131: 6088–892. Egashira N, Morita S, Hifumi E, Mitoma Y, Uda T. Anal Chem 2008; 80: 4020–253. Verschraegen I, Anckaert E, Schiettecatte J, Mees M., Garrido A, Hermsen D, et al. Clin Chem.

Acta 2007; 380: 75–804. Santini S A, Carrozza C, Vulpio C, Capoluongo E, Luciani G, Lulli P, et al. Clin Chem 2004; 50:

1247–505. Merrill G A, Rivera V R, Neal D D, Young C, Poli M A, Anal Biochem 2006; 357: 181–876. Rivera V R, Gamez F J, Keener W K, White J A, Poli M A. Anal Biochem 2006; 353: 248–567. Garber E A, Walker J L, O’Brien T W. J Food Prot 2008; 71: 1868–748. Pittman T L, Thomson B, Miao W J. Anal Chim Acta 2009; 632: 197–02

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PM-F1F2-02-02

Fabrication of hybrid bilayer membrane for direct electrochemistry of myoglobin

Saima Anjum1, Aziz-ur-Rehman1, Guobao Xu2

1Department of Chemistry, Baghdad-ul-Jadeed Campus, The Islamia University of Bahawalpur, Ba-hawalpur, Pakistan

2 State Key Laboratory of Electroanalytical Chemistry, Changchun Institute of Applied Chemistry, Chinese Academy of Sciences, Changchun, Jilin 130022, PR China

Alkanethiol generally form self-assemble monolayer on gold electrodes and the electrochemical reduc-tion of aromatic diazonium salts is a popular method for covalent modification of carbon. Based on the reaction of alkanethiol with aldehyde groups covalently bound on carbon surface by the electrochemi-cal reduction of aromatic diazonium salts, a new strategy for the modification of carbon electrodes with alkanethiols is developed. The modification of carbon surface with aldehyde groups is achieved by the electrochemical reduction of aromatic diazonium salts in situ electrogenerated from nitro precursor, p-nitrophenylaldehyde, in the presence of nitrous acid. By this way, in situ electrogenerated p-amino-phenyl aldehyde from p-nitrophenylaldehyde immediately reacts with nitrous acid, effectively mini-mizing the side reaction of amine groups and aldehyde groups. The as-prepared alkanethiol-modified glassy carbon electrode was further used to make biomembrane-like films by casting didodecyldimeth-ylammonium bromide (DDAB) on its surface. The biomembrane-like films enable direct electrochem-istry of immobilized myoglobin (Mb) for the detection of hydrogen peroxide (H2O2). The response was linear over the range 1-600 µM with a detection limit of 0.3 µM.

Keywords: Carbon electrodes, Alkanethiol, Diazonium salts, Biomembrane-like films,

Ali, B., David, J. G., Alison, J. D, 2012. J. Electrochem. Sci 7,3141 - 3154.

Allongue, P., Delamar, M., Desbat, B., Fagebaume, O., Hitmi, R., Pinson, J., Saveant, J. M.,

1997. J Am Chem Soc 119(1), 201-207.

Armstrong, F. A., Cox, P. A., Hill, H. A. O., Lowe, V. J., Oliver, B. N.,1987. J. Electroanal. Chem 217, 331–366.

Bain, C. D., Troughton, E. B., Tao, Y. T., Evall, J., Whitesides, G. M., Nuzzo, R. G., 1989

J. Am. Chem. Soc 111,321.

Chi, Q. J., Zhang, J. D., Nielsen, J. U., Friis, E. P., Chorkendorff, I., Canters, G. W., Andersen, J.

E. T., Ulstrup, J., 2000. J Am Chem Soc 122 (17), 4047-4055.

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PM-F1F2-02-03

Bright Functional Herceptin Conjugates with a Remarkably High Number of Fluorophores for Optical Imaging

Jutta Pauli 1, Joanna Napp 2, Marieke Plochstein 1, Julia Streng 1, Frauke Alves 2, Ute Resch-Genger 1

1 BAM Federal Institute for Materials Research and Testing, Richard-Willstätter-Str. 11, D-12489 Berlin, Germany, E-mail: [email protected]

2 Max-Planck-Institute for Experimental Medicine, Department of Molecular Biology of Neuronal Signals, Hermann-Rein-Str. 3, 37075 Göttingen, Germany

Introduction: Achievable detection limits of fluorescence imaging methods using fluorescent protein conjugates are largely determined by the brightness of the conjugates.The obtainable fluorescence signal is mainly controlled by the molar absorption coefficient and the fluorescence quantum yield (FF) of the protein-bound dyes and the suppression of the formation of non-fluorescent dye dimers upon protein labeling (1,2). Dimer formation can be reduced by increasing the hydrophilicity of fluorophores, but cannot be completely suppressed even for dyes with a high number of sulfonate groups (3). Therefore, the search for new dyes absorbing and emitting in the near infrared (NIR) and the development of methods to prevent the formation of non fluorescent dimers is an actual challenge in the field of optical imaging. In this context we studied the spectroscopic properties of novel Cy5-based NIR fluorophores and their herceptin conjugates in the presence of surfactants. We tested their functionality by binding on Her-2/neu-expressing BT-474 cells.

Materials and Methods:Herceptin (Her) was coupled to NIR fluorophores (FEW Chemicals) and Cy5 (Amersham Biosciences Europe GmbH) at different dye-to-protein (D/P) ratios via NHS-chemistry. The Her conjugates were characterized in PBS by absorption and fluorescence spectroscopy. Functionality of the Her-Dye conjugates was evaluated on Her-2/neu-expressing BT-474 in comparison to Her-2/neu negative MDA-MB-231 mammary carcinoma cells. Fluorescence microscopy studies were done with the Zeiss Axiovert 200 M microscope (Carl Zeiss) equipped with a NIR-sensitive ORCA-ER digital camera (Hamamatsu).

Results:The new NIR dyes display similar absorption coefficients and enhanced fluorescence quantum yields in comparison to those of the often used dye Cy5. The labeling degrees and FF of the herceptin conjugates with the new dyes exceed those of the Her-Cy5 conjugates at comparable dye-to-protein ratios. Binding of the highly labeled Her conjugates to Her-2/neu-expressing BT-474 cells demonstrates their functionality despite the high degree of labeling. Suitable additives prevent the dimerization of the new NIR dyes upon binding to the protein.

Literature:

(1) Ogawa, M. et al. ACS Chem. Biol. (2009) 4, 535-546.

(2) Pauli, J, et al. Bioconjugate Chem. (2011) 22,1298-1308.

(3) Pauli, J, et al. Bioconjugate Chem. (2013) 24, 1174-1185.

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PM-F4-02-01

Improved Analysis of Trace Elements in Environmental Samples using Sulfonated Polystyrene Microparticles in Combination with ETV-ICP-OES Analysis

S. Hossein Zadegan1, W. Nischkauer 1, 2, M.-A. Néouze3 and A. Limbeck1

1 Vienna University of Technology, Getreidemarkt 9, 1060 Vienna, Austria. 2 Ghent University, Krijgslaan 281 / S12, 9000 Ghent, Belgium.

3 Ecole Polytechnique, 91128 Palaiseau, France.


Polystyrene particles have found many applications in different fields of science including biology, pharmacology and chemistry due to their unique characteristics such as ideal mechanical strength, adjustable particle size, and favorable chemical stability [1]. Moreover, they can be easily functionalized and these reactive end chains act as an adsorbent for metal ions.

In this contribution, such kind of non-metallic adsorbent is combined with dispersed particle extraction (DPE) for the first time. DPE is an improved solid phase extraction (SPE) based method and has been previously used by our group as an enrichment and matrix separation method for multiply charged cations, prior to ICP-OES analysis [2, 3]. The silica based nanoparticles used as sorbent material in the previous works are well suited for liquid slurry analysis, but in the case of analysis with electro thermal vaporization (ETV), the use of nanoparticles with considerable thermal stability (silica) might result in contamination of the ETV system, or may cause problems during analysis, respectively.

In order to avoid these drawbacks, we present a new method for trace metal enrichment prior to ETV-ICP-OES analysis. Amphiphilic solfunated polystyrene/polystyrene (SPS/PS) microparticles were synthesized using seed microsphere with a strong hydrophilic surface [4]. These particles were successively suspended into the pH-adjusted liquid samples containing analytes at controlled pH (ammonium buffer system). After separation of the analyte containing particles by centrifugation, the slurry was introduced into the ETV. The polymeric particle cores can be vaporized easily and allow for a straight-forward quantification of remaining REEs via ICP-OES.

In comparison to liquid sample introduction, application of ETV further improves the enrichment factor of the DPE procedure, as it is possible to reduce the final volume obtained after DPE sample pre-treatment to a few microliters. Thermal separation of the organic sorbent particles prior to analyte measurement is another benefit reducing the possibility of matrix induced interferences.

References

1. Ma. G-H, Zhou. W-Q, et al, Journal of Molecular Catalysis B: Enzymatic. 66, 182 (2010).

2. G. Bauer, M.-A. Neouze and A. Limbeck, Talanta. 103, 145 (2013).

3. R. Janski, M.-A. Neouze and A. Limbeck, Rapid Communications in Mass Spectrometry. 4. Wang. G, et al, Polymer. 55, 1948 (2014).

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PM-F4-02-02

Direct Analysis in Real-Time / Orbitrap Mass Spectrometry as a Tool for The Direct, Global Characterization and Differentiation of Explosive Samples For

Forensic Application

Maxime C. Bridoux1, Adrian Schwarzenberg2, Xavier Machuron-Mandard1, Jean-Claude Tabet2, Richard B. Cole2

1CEA, DAM, DIF, F-91297 Arpajon, France 2UPMC, IPCM/CSOB, UMR 8232, 4 Place Jussieu, 75252 cedex 05, Paris, France


The ability to fully characterize, at the molecular level, the formulation of explosives, from trace amounts of samples, is beneficial for homeland security and forensic applications. In fact, most explosives are composed of a charge (which consist of a single or a mixture of energetic compounds such as TNT, RDX, PETN…), which is diluted in a complex matrix of binders, plasticizers, polymers, oils and a series of other organic additives and contaminants, whose characterization can significantly help identify the source, geographic origin of the explosive as well as the manufacturing process and possibly even the lot number.

The goal of the work described here is to evaluate the capabilities of an ambient ionization method known as “Direct Analysis in Real Time” (DART), combined to high resolution Orbitrap mass spectrometry, for the global characterization of explosive samples for forensic application. From a forensic practical point of view, the detection technique employed to characterize the explosive material should ideally be a fast, real-time analysis with a high accuracy and resolution and, from a minimum quantity of sample, without involving complex sample preparation. Such requirements are fulfilled here by the hyphenation of DART, to an Orbitrap mass spectrometer. In this work, a series of cotton swipe samples were collected from military plastic and non-plastic explosives, including mines, rockets and mortars, originating from various geographical locations. We will show in this poster presentation that DART-Orbitrap MS allowed the global characterization of explosive formulation from the swipe samples, in that the explosive charges (TNT, RDX, HMX, PETN) were identified as either deprotonated species or as nitrate or chloride adducts in negative mode. Switching to a positive mode of ionization revealed the presence of copolymer binders, plasticizers, and other additives, identified either as protonated or ammonium adduct species. These results clearly demonstrate the capability of DART/Orbitrap-MS as a tool for the direct, global characterization and differentiation of samples for forensic applications.

DIRECT ANALYSIS IN REAL-TIME / ORBITRAP MASS SPECTROMETRY AS A

TOOL FOR THE DIRECT, GLOBAL CHARACTERIZATION AND

DIFFERENTIATION OF EXPLOSIVE SAMPLES FOR FORENSIC APPLICATION

Maxime C. Bridoux1‡, Adrian Schwarzenberg2‡, Xavier Machuron-Mandard1, Jean-

Claude Tabet2, Richard B. Cole2 1CEA, DAM, DIF, F-91297 Arpajon, France

2UPMC, IPCM/CSOB, UMR 8232, 4 Place Jussieu, 75252 cedex 05, Paris, France Presenting author: [email protected]

The ability to fully characterize, at the molecular level, the formulation of explosives, from trace amounts of samples, is beneficial for homeland security and forensic applications. In fact, most explosives are composed of a charge (which consist of a single or a mixture of energetic compounds such as TNT, RDX, PETN…), which is diluted in a complex matrix of binders, plasticizers, polymers, oils and a series of other organic additives and contaminants, whose characterization can significantly help identify the source, geographic origin of the explosive as well as the manufacturing process and possibly even the lot number. The goal of the work described here is to evaluate the capabilities of an ambient ionization method known as “Direct Analysis in Real Time” (DART), combined to high resolution Orbitrap mass spectrometry, for the global characterization of explosive samples for forensic application. From a forensic practical point of view, the detection technique employed to characterize the explosive material should ideally be a fast, real-time analysis with a high accuracy and resolution and, from a minimum quantity of sample, without involving complex sample preparation. Such requirements are fulfilled here by the hyphenation of DART, to an Orbitrap mass spectrometer. In this work, a series of cotton swipe samples were collected from military plastic and non-plastic explosives, including mines, rockets and mortars, originating from various geographical locations. We will show in this poster presentation that DART-Orbitrap MS allowed the global characterization of explosive formulation from the swipe samples, in that the explosive charges (TNT, RDX, HMX, PETN) were identified as either deprotonated species or as nitrate or chloride adducts in negative mode. Switching to a positive mode of ionization revealed the presence of copolymer binders, plasticizers, and other additives, identified either as protonated or ammonium adduct species. These results clearly demonstrate the capability of DART/Orbitrap-MS as a tool for the direct, global characterization and differentiation of samples for forensic applications.

Figure 1: DART-Orbitrap MS analysis of cotton swipes from a military grade plastic explosive

DART-OT (+)

DART-OT (-)

Figure 1: DART-Orbitrap MS analysis of cotton swipes from a military grade plastic explosive

DART-OT (+)DART-OT (-)

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PM-F4-02-03

CATION BINDING STUDY OF CROWN CONTAINING FERROCENYL NAPHTAQUINONES: SPECTROPHOTOMETRIC DETERMINATION

Y.Alçay1, M. Dağdevren1, İ. Yılmaz1*

1Istanbul Technical University, 34469, Istanbul, TurkeyPresenting author: [email protected]

Crown containing compounds undergo photophysical changes upon cation binding [1]. In this study some alkali and alkaline earth metals complexed with benzo-18-crown-6 containing ferrocenyl naphtaquinones [2]. Depending on the charge density of cations, the absorption spectra are markedly red shifted [3]. The stoichiometry of all complexes were 1:1 and the stability constants were measured by the degree of red shifts [4].

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Figure 1. Absorption spectra of metal-crown complexes

* This work is supported by the Scientific and Technological Research Council of Turkey (TÜBİTAK) (Project Number: 113Z309)

References1. B. Valeur, J. Phys. Chem. 97, 4552 (1993).2. B. Yücel, B. Şanlı, H. Söylemez, İ. Yılmaz, Tetrahedron 67, 1406 (2011)3. B. Valeur, I. Leray, Coordination Chemistry Reviews 205, 3 (2000)4. C. J. Pedersen, H. K. Frensdorff, Angew. Chem. Internat. Edit. 11, 16 (1972)

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PM-F4-02-04

MASSIVE PLASTIC SORTING BY USING RAMAN IDENTIFICATION

H. Kawazumi1, A. Tsuchida2, Y. Tsuchida2

1Kinki University, School of Industrial Technology, 820-8555, Iizuka, Japan2Saimu Corporation, 820-0609, Keisen, JapanPresenting author: [email protected]

Globally, plastic recycling is an important issue because the original resource for most plastics is petroleum. There are several approaches to plastic recycling in industrial fields, e.g., thermal, chemical and mechanical. Among these, mechanical recycling is the most effective in reducing the environmental burden. Mechanical recycling however currently produces low-grade plastic commodities from low-purity and mixed plastics. Well-designed collection schemes and state-of-the-art sorting and refining technology provide highly purified post-consumer plastic pieces that can be transformed into regenerated products related to the original products; so-called closed-loop recycling. We have developed a plastics sorting system for the shredder dust from used home appliances. A practical-scale factory has been operated in a monthly throughput of more than 200 tons for two years at the Kansai region. Three major plastics (PP, PS, ABS) are collected with a purity of 95 – 99 % and supplied for material and/or closed-loop recycling for the electric appliances. In this paper, we would present in detail the sorting system.

The key technologies in our sorting system are well-arranged preprocessing system, refined specific gravity classify- cation and Raman spectroscopy identification. Figure 1 shows the schematic of the large-scale plastic sorting system including 50 on-line Raman apparatuses above a 25-cm-wide conveyor (speed: 100 m/minute); in Figure 1, only three Raman units are shown. The plastic mixture is classified into PP and PS/ABS fractions in a water tank based on the differences in specific gravity after the suitable preprocessing. The refined water tank procedure provides the purity of 99 % for the

collected PP. Finally, the plastic pieces are fed to the system that uses the Raman identifiers to improve the purity of PP or to classify PS and ABS. At the end of the conveyor an array of pulsed air blasts directs the selected plastics into the appropriate container. This large-scale, accurate sorting system requires the acquisition of Raman spectra with adequate signal-to-noise ratios in a short measuring time. The spectra of the three major plastics exhibit distinctive peaks in the 3-ms measurement by using our originally developed Raman identifier.

Figure 1: Diagram of massive plastic sorting system.

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PM-F4-02-05

EFFECTIVE DETERMINATION OF NSAIDS BY DISPERSIVE LIQUID-LIQUID MICROEXTRACTION (DLLME) AND HPLC

Seung-Woon Myung

Department of Chemistry, Kyonggi University, Rep. of Korea

Dispersive liquid-liquid microextraction ( DLLME ) may be utilized as a green chemistry approach to reduce the consumption of hazardous organic solvents in the chemical analysis. A simple and efficient sample preparation method was developed using DLLME prior to HPLC/UV analysis for simultaneous extraction and determination of trace amounts of Non-Steroidial Anti-Inflammatory Drugs (NSAIDs) including indoprofen, ketoprofen, naproxen, diclofenac, ibuprofen, mefenamic acid, and tolfenamic acid from an aqueous sample. Optimal dispersive solvent and extraction solvent were acetonitrile and chloroform, respectively, and showed increased enrichment factor (EF = 9~18) for NSAIDs. Simul-taneous chromatographic separation of seven NSAIDs by HPLC-UV/Vis system was achieved on an Eclipse XDB-C18 (4.6 mm i. d. × 150 mm length, 5 μm particle size) column using isocratic elution with 0.1% formic acid and methanol (30:70). NSAIDs were extracted and concentrated from 5 mL of aqueous solution with pH 3.2. The volume of dispersive and extraction solvent were 1000 μL and 200 μL, respectively. After the extraction, 2 μL of extract was directly injected into the HPLC/UV system. The developed method represents a simple, rapid, environmentally friendly and inexpensive sample preparation method.

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PM-F4-02-06

SEDIMENTATION FIELD-FLOW FRACTIONATION USING ROTATING COILED COLUMNS IN THE ANALYSIS OF POLYDISPERSE PARTICULATE SAMPLES

M.S. Ermolin1,2, P.S. Fedotov1,2, O.N. Katasonova2, B.Ya. Spivakov1,2

1 National University of Science and Technology “MISIS”, 119049 Moscow, Russia 2 Vernadsky Institute of Geochemistry and Analytical Chemistry, Russian Academy

of Sciences, 119991 Moscow, Russia

[email protected]

Fractionation of nano- and microparticles is required in macromolecular chemistry, biochemistry, nanotechnology, environmental studies, and other fields of science and technology. The size distribution of nano- and microparticles may strongly affect the characteristics of various functional materials. Furthermore, particles of different size frequently have different chemical composition and properties that cannot be conveniently studied unless the particles are fractionated. A number of techniques employed for fractionation of particles in liquid media exemplify relevance and difficulty of this problem.

Field-flow fractionation (FFF) is a very powerful and versatile fractionation and sizing method applicable to marcomolecules and particles in the range from about 1 nm to 100 mm. The main limitation of FFF is the weight of handling particulate sample that is usually less than 1 mg. The fractionation in a rotating coiled column (RCC), which can be attributed to sedimentation FFF, enables this limitation to be avoided. The technique employs a complex asymmetrical force field generated in planetary centrifuges. The mixture of particles is pumped with carrier fluid through a long RCC of 1.5 mm tubing bore and 10-20 mL inner capacity. In such a way the handling of 100-500 mg of a polydisperse sample becomes possible and fractions of particles in submicron and micron size ranges can be successfully separated [1].

Natural quartz sand particles (1-20 µm, reference sample BCR-70) with irregular geometry have been fractionated in RCC. The method was also applied to the separation of soils into silt, clay and sand fractions [3]. For the first time, nano- and submicron particles of street dust have been separated, weighted, characterized by electronic microscopy, and quantitatively analyzed by ICP-MS (after digestion). The elements that may be of anthropogenic origin (Zn, Cr, Ni, Cu, Cd, Sn, Pb) were found to concentrate mainly in <0.3 and 0.3-1 mm fractions. It has been shown that the contents of Cr, Ni, Zn in the finest fraction (<0.3 mm) of street dust can be one order of magnitude higher than the contents of elements in bulk sample. Study on the fractionation of different synthetic samples has demonstrated the applicability of the method to obtaining narrow-size particle fractions and quality control of polydisperse functional materials.

The authors would like to acknowledge financial support from the Ministry of Education and Science of the Russian Federation (Program of Increasing Competitiveness of NUST «MISIS», project No К1-2014-026) and the Russian Foundation of Basic Research (project No 14-03-00128).

References

1. P.S. Fedotov, N.G. Vanifatova, V.M. Shkinev, B.Ya. Spivakov, Anal. Bioanal. Chem., 400, 1787 (2011).

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PM-F4-02-07

FORMATION AND NATURAL OCCURRENCE OF THIOMOLYBDATES

R. Lohmayer1, G. Reithmaier1, E. Bura-Nakić², B. Planer-Friedrich1

1University of Bayreuth, Environmental Geochemistry, Bayreuth Center for Ecology and Environmen-tal Research (BayCEER), 95440 Bayreuth, Germany

²Division for Marine and Environmental Research, Ruđer Bošković Institute, HR-10002 Zagreb, Croatia Presenting author: [email protected]

The occurrence of molybdenum in sediments can provide important information about reducing con-ditions during the time of deposition. To gain insights in the underlying precipitation mechanisms, mo-lybdenum speciation in the aqueous phase was modelled for Lake Rogoznica in Croatia [1]. The sea-water lake is clearly stratified from winter to late summer with a sharp increase in sulfide and decrease in molybdenum concentrations at around 10 m. The appearance of a constant limiting molybdenum concentration was ascribed to the formation of tetrathiomolybdate and the following precipitation of an iron-molybdenum-sulfide mineral. Formation of mono- to tetrathiomolybdate in synthetic solutions was already shown by UV-visible spectroscopy with the highest stability but slowest reaction kinetics for tetrathiomolybdate [2].A method for thiomolybdate quantification was published for HPLC combined with conductivity de-tection [3]. The eluent contained 25% acetonitrile using isocratic conditions. Based on this publica-tion, we established a gradient program to optimize sufficient peak separation between molybdate and monothiomolybdate but also rapid elution of tetrathiomolybdate. Molybdenum species were measured by UV detection at 254 nm. With the optimized method we investigated thiomolybdate formation from molybdate and sulfide or polysulfides at different pH values and different Mo:S ratios. Tetrathiomolyb-date formation increased with increasing sulfide excess and was much faster at pH 7 in comparison to pH 8. After 7 days, around 80% of the initially applied molybdate was transformed to tetrathiomolyb-date by tenfold sulfide excess. Moreover, we tested tetrathiomolybdate stability under different storage conditions (light and dark at room temperature, frozen) and found it to be stable under all conditions for at least 7 days.Further, we adapted the analytical method to be able to use ICP-MS as detection system and thereby enable the measurement of thiomolybdate species in natural matrices and at environmentally relevant concentrations (nanomolar range). Therefore, acetonitrile from the eluent had to be replaced, as the plasma is extinguished at acetonitrile concentrations higher than 10%. So, we tested different alter-native organic solvents (methanol, iso-propanol, n-propanol) with and without column heating and addition of 30 mL/min O2 to the spray chamber to oxidize excess organic carbon. With this alternative analytical method, we will measure thiomolybdate species in water samples taken in February 2014 over the whole depth profile of Lake Rogoznica for which previously formation of predominantly tetra-thiomolybdate has been predicted at depths below 10 m. This will give new insights in the role of sulfur redox chemistry for the mobilisation or immobilisation of molybdenum.

Reference1. G. R. Helz, E. Bura-Nakić, N. Mikac, I. Ciglenečki, Chem. Geol. 284, 3-4 (2011).2.B. E. Erickson and G. R. Helz, Geochim. Cosmochim. Acta 64, 7 (2000).3. J. Weiss, H. J. Möckel, A. Müller, E. Diemann, H.-J. Walberg, J. Chromatogr. 439, 1 (1988).

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