Centre en chimie verte et catalyse - McGill...

Centre en chimie verte et catalyse

La chimie réinventée pour un avenir plus propre

Chemistry reinvented for a cleaner tomorrow

Centre in Green Chemistry and Catalysis

P-01 Higly recyclable beta-cyclodextrin-based ligand for Suzuki-Miyaura cross coupling reaction in water

Vanessa Kairouz and Andreea Schmitzer (Département de chimie, Université de Montréal)

We present the synthesis and the catalytic properties of a novel alkyl imidazolium modified -cyclodextrin. The introduction of the alkyl imidazolium motif on the primary face of the -

cyclodextrin allows the development of a green catalyst for reactions performed in water. This concept was applied for the Suzuki-Miyaura coupling, where a new efficient catalytic system in neat water, under mild conditions, without use of cosolvent or stabilizing phosphine ligands was developed.

P-02 Hydrodynamics of two-phase flow in catalytic micro-packed beds Ali Faridkhou and Faical Larachi

(Département de génie chimique, Université Laval)

Catalytic micro-packed beds are part of the initiative to advance green chemistry by minimizing waste production. To improve their efficiency, hydrodynamic studies aim to enhance the contacting patterns between the phases. Current work investigates the key hydrodynamic parameters of micro-packed beds (e.g. pressure drop and liquid holdup for different gas-liquid-solid systems). Also, microscopic visualizations were obtained from the reactor and images subsequently processed to extract data regarding the flow regimes within the bed and their evolution along its length. Pressure drop and wetting pattern hysteresis as well as the transient behaviour of micro-packed beds were also studied.

P-03 A new Synthetic Route to Asymmetric Tetradentate Azadipyrromethenes: Impact on the Electronic and Photophysical

Properties as compared to their Symmetric Counterparts André Bessette1,2, Mihaela Cibian1, Francis Bélanger, Denis Désilets2 &

Garry S. Hanan1 (1Départment de chimie, Université de Montréal, 2St-Jean-Photochimie Inc.)

As analogues of porphyrinoids and dipyrromethene families of dye, azadipyrromethene (ADPM) derivatives exhibit exciting photophysical properties. In the present study, we endeavoured a comparative study of symmetric and asymmetric tetradentate ADPM derivatives 1 – 6 vs reference bidentate motifs of 7 and 8 in order to gain insights on their structure – property relationship. A new straightforward synthetic approach for asymmetric derivatives 4 – 6 is proposed. In addition, photophysic, electrochemistry, X-ray structural characterization and computational modelization are used to better understand the high potential of these new chromophores in light-harvesting and catalytic applications.





P-04 Efficient Macrocyclic Cu(I)-Catalyzed Cycloaddition of Iodoalkynes and Azides via a Phase Separation Strategy

Anne-Catherine Bédard and Shawn K. Collins (Département de chimie, Université de Montréal)

A novel and efficient macrocyclic CuI-catalyzed azide-iodoalkyne cycloaddition (CuAiAC) process has been developed. The strategy employs a phase separation strategy using low catalyst loadings at relatively high concentrations (30 mM→300 mM). A variety of macrocyclic skeletons could be prepared having either different alkyl, aryl or amino acid spacers (70-97 %).The macrocyclic CuAiAC process affords macrocycles having an iodotriazole moiety that can be further functionalized using standard Pd-catalyzed cross-couplings.

P-05 Integrated biomass torrefaction - chemical looping combustion as a method to recover torrefaction volatiles energy

Amin Sarvaramini and Faical Larachi (Département de génie chimique, Université Laval)

Hyphenation of biomass torrefaction to chemical looping combustion (CLC) was studied experimentally. The concept consists of burning the torrefaction volatiles using iron oxide bearing mining residues as solid oxygen carrier whereby the combustion flue gas, mostly non-diluted CO2 and steam, is recirculated to the torrefaction reactor for heat integration. In this regard, birch wood was torrefied between 260°C and 300°C and the resulting volatiles were burned over iron-containing silicate minerals as oxygen carriers between 500°C and 700°C with volatile carbon converted up to 97% into CO2. The potential of mining residues for sequestration of CO2 produced in the CLC reactor was also tested in this study. Using the concept presented in this study, biomass as a green and renewable source of energy can be converted to a higher quality fuel in an auto thermal route while the produced carbon dioxide is also sequestrated which leads to a negative net CO2 process.

P-06 Rhodium-Catalyzed Stereoselective Amination of Thioethers with N-Mesyloxycarbamates

Henri Piras and Hélène Lebel (Département de chimie, Université de Montréal)

A stereoselective Rh-catalyzed intermolecular amination of thioethers using readily available chiral N-mesyloxycarbamate to produce a variety of chiral sulfilimines in excellent yields and diastereoselectivities is described. A catalytic mixture of DMAP and BisDMAPCH2Cl2 proved pivotal in achieving high efficiency and selectivity. Cyclic voltammetry studies showed that the DMAP-Rh(II) dimer complex has a significantly lower oxidation potential than the parent Rh2[(S)-nttl]4 complex, suggesting a Rh(II)-Rh(III) complex as the catalytic active species.





P-07 Asymmetric Synthesis of the Main Core of Kaurane Family Members Triggered by an Oxidative Polycyclisation-Pinacol Tandem Process

Gaëtan Maertens and Sylvain Canesi (Département de chimie, Université du Québec à Montréal)

We propose an asymmetric synthesis of the main tetracyclic core of natural diterpenes belonging to the large family named Kaurane. Our strategy is based on cationic polycyclisations of poly-unsaturated compounds concluded by a pinacolic rearrangement, two powerful synthetic tools that can provide quick access to complex natural structures with high selectivity. Moreover, our interest in oxidative dearomatization of electron-rich aromatics compounds led us to envisage triggering the polycyclisation cascade by formation of a phenoxonium ion. The later results from the activation of the functionalized phenol with PIFA, an environmentally benign hypervalent iodine reagent.

P-08 Catalytic enantioselective iodine(III)-mediated alpha-tosyloxylation of ketones : Recent progress

Benoit Basdevant, Audrey-Anne Guilbault, Vincent Wanie, and Claude Y. Legault

(Département de chimie, Université de Sherbrooke)

Iodine(III) reagents are of interest as they are polyvalent electrophiles and mild oxidants. They are an alternative to toxic transition metals often used to effect similar transformations. An interesting iodine(III)-mediated reaction is the α-oxidation of carbonyl compounds which allow to introduce a nucleophile to functionalize ketone. This type of reaction can be rendered catalytic and enantioselective by the use of chiral iodine(I)-based catalysts. To improve enantioselectivities we developed a new class of catalysts based on iodoaryloxazolines and we evaluated their activity and selectivity.1

1.Legault, C. Y.; Guilbault, A.-A.; Basdevant, B.; Wanie, V. J. Org. Chem. 2012, 77, 11283-11295.

P-09 Study of the electrophilic potential of diazirines and application to the synthesis of pyrazoles

Yoann Schneider and Claude Y. Legault (Département de chimie, Université de Sherbrooke)

Diazirines are well-known molecules, with the ability to be a source of electrophilic nitrogen. Yet, this potential was never truly exploited. The diazirine derived from adamantanone can circumvent the issues that prevented its wide use. Additions of nucleophilic reagents lead to the formation of corresponding N-monosubstituted species. They can release corresponding hydrazines, which are converted to pyrazoles in high yields. The adamantanone can be recovered in 80-100% yields. This methodology demonstrates the potential of diazirines as electrophilic nitrogen sources with recoverable protecting groups.





P-10 Application of cloud point extraction in environmental matrices Charles Labrecque and Dominic Larivière

(Laboratoire de Radioécologie, Université Laval)

In emergency situations, it is important to have well established and rapid methods to establish the extend contamination. Among the available strategies, cloud point extraction (CPE) has shown multiple advantages such as its high preconcentration factor and its green character over its liquid-liquid extraction counterpart. In our laboratory, strategies were developed to perform the determination of actinides and rare earth elements in a wide range of matrices. The developed approaches were significant improvements over current strategies as they were proven to be applicable to digested solid matrices

P-11 Controlled Assembly of Semi-Quinone Radical Based Materials in the Solid State

Martin J. Glavinović, Feng Qi, Athanassios D. Katsenis, Cristina Motillo, Jean-Philip Lumb and Tomislav Friščić

(Department of Chemistry, McGill University)

Magnetic metal-organic hybrids attract interest as redox active materials with potential applications in high-density data storage. Herein, we demonstrate the mechanochemical redox of bulk Zinc metal with quinone ligands coupled with coordination-driven self-assembly to provide multi-nuclear and polymeric metal-semiquinone radical architectures. Our work uses a low-energy, solvent-free approach and couples mechanochemical processes with targeted organic synthesis.

P-12 Palladium-Catalyzed Carbonylative C-H Functionalization of Heterocycles Jevgenijs Tjutrins and Bruce A. Arndtsen


Transition metal catalyzed C-H functionalization reactions of arenes and heteroarenes is becoming of great significance for preparation of pharmaceutically active scaffolds and building blocks for organic synthesis. Comparing to classical cross coupling methodologies, these methods do not require the need of stoichiometric amounts of organometallic reagents, thus provide us with greater atom economy. Here in we present a palladium catalyzed carbonylative coupling of aryl halides and various heterocycles as a modular route towards di-(hetero) aryl ketones. The details of this reaction mechanism, catalyst development, and product scope will be discussed.





P-13 A Catalytic Aerobic Platform for the Synthesis of Polyfunctional Heterocycles

Zheng Huang, Tian-Yang Dai, Kenneth Virgel N. Esguerra, Ohhyeon Kwon and Jean-Philip Lumb

(Department of Chemistry, McGill University) Heterocycles are fundamentally important to the function of pharmaceuticals, agrochemicals and materials, motivating considerable efforts to improve the efficiency of their synthesis. Our group has recently developed a biomimetic approach to heterocycles synthesis, which hinges on a catalytic aerobic ortho-oxygenation of phenols into ortho-quinones. ortho-Quinones are versatile synthetic intermediates that enable the direct synthesis of a range of heterocycles via addition and condensation reactions. This provides a streamlined approach to heterocycles that begins from readily available phenol starting materials, and that produces H2O as the sole stoichiometric byproduct.

P-14 Palladium-Catalyzed, Picolinamide-Enabled C(sp3) -H Arylation: A Practical Functionalization of the Cyclopropyl Scaffold

Daniela Sustac Roman and André B. Charette (Département de chimie, Université de Montréal)

The design of low-cost, waste-free, catalytic and efficient C-H arylation strategies is a highly sought goal in organic chemistry. Cyclopropanes are an attractive target for C-H functionalization, due to their importance in medicinal chemistry and natural product synthesis. Herein, we describe two efficient and catalytic processes for the C-H arylation of cyclopropyl picolinamides with various aryl iodides. The first condition employs a palladium catalyst, catalytic amounts of a carbonate base and a silver salt, while the second condition employs a palladium catalyst, catalytic amounts of pivalic acid and a carbonate base. The reaction gives rise to only one diastereomer, can be performed on large-scale, and the picolinamide auxiliary can be removed under mild conditions.

P-15 A Palladium-Catalyzed Carbonylation Approach to Acid Chloride Synthesis

Jeffrey S. Quesnel and Bruce A. Arndtsen (Department of Chemistry, McGill University)

Acid chlorides are common reagents employed in organic synthesis, with examples including acylating reactions, Friedel-Crafts chemistry, as well as polymer synthesis. However, their synthesis is usually from the corresponding carboxylic acid from harsh and wasteful halogenating reagents. We recently described a unique and atom economical approach to acid chloride synthesis: via the palladium-catalyzed coupling of aryl halides, CO, and simple chloride salts.1 By rational catalyst design, these highly reactive reagents can be generated in situ under mild conditions to react with nucleophiles. By modifying the reaction conditions, these acid chlorides can also be prepared for isolation.

1. Quesnel, J. S., Arndtsen, B. A. J. Am. Chem. Soc. 2013, 135, 16841.





P-16 Multicomponent Assembly of Conjugated Polymers Laure V. Kayser, David C. Leitch, Zhiyong Han and, Bruce A. Arndtsen


Conjugated polymers have emerged over the past decades as an interesting class of materials with applications as semiconductors, transistors, OLEDs, and in photovoltaics. However, their multistep synthesis is often a limitation for their large-scale production. In this context, a greener and more modular synthetic method from simple starting materials could prove useful. To address these challenges, we have developed multicomponent polymerization platforms. These approaches use simple starting materials to generate conjugated polymers with a complex repeat unit in one-pot. New families of conjugated polymers with tunable properties can be easily accessed by changing each of the monomers.

P-17 What Goes Around Comes Around: Translation of Chemical Risks into Business Risks

Arash Amirkhany and Steve Maguire (Desautels Faculty of Management, McGill University)

This paper introduces, theorizes and provides empirical support for the concept of “risk translation” – the social processes through which risks to human health or the environment produced by an organization become transformed into risks to the organization. Through a systematic review of published reports linking the use of hazardous substances by a firm to negative consequences for the firm, we develop a typology of business risks derived from chemical risks. We identify and explore similarities and differences across different risk translation processes. We conclude by discussing implications of green chemistry for risk translation.

P-18 Rhodium catalyzed intramolecular C-H amination: Synthesis of oxazolidinones

Maroua Khalifa and Hélène Lebel (Département de chimie, Université de Montréal)

Oxazolidinones are a new class of synthetic antimicrobial agents. Recently, our research group has developed an efficient methodology to perform intramolecular C-H insertion using organometallic rhodium (II) dimer as a catalyst and N-mesyloxycarbamates as nitrene precursors. This direct intramolecular process provided a convenient access to oxazolidinones without the need of prefunctionalization. Hereby, we want to report novel reaction conditions with halo-substituted aryl N-mesyloxycarbamates. In addition, a new mechanistic hypothesis will be discussed.





P-19 Abundant Metal Complexes to Catalyze Intramolecular C-H Amination Reactions

Laura Mamani Laparra, Davit Zargarian, Hélène Lebel (Département de chimie, Université de Montréal)

A few years ago, our group developed a methodology to efficiently produce oxazolidinones, an important biologically active heterocycle, via rhodium-catalyzed C-H aminations of N-sulfonyloxycarbamates. As rhodium complexes are expensive scarce resources, we are currently investigating metal catalysts derived from abundant metals to achieve C-H amination reactions. Hereby, we wish to disclose encouraging preliminary results from the screening of suitable metal catalysts, including iron(III) phtalocyanin chloride.

P-20 Aerobic Oxidation of 2-Silyloxyfurans: Green and Scalable Synthesis of g-Hydroxybutenolides

Marc-Alexandre Jean and John Boukouvalas (Département de chimie, Université Laval)

P-21 New Classes of Lewis-Acid Tethered Imine Ligands: Synthesis and Coordination to Palladium

Fabio Lorenzini and Bruce A. Arndtsen (Department of Chemistry, McGill University)

Lewis acid tethered ligands have become of growing importance in the discovery of new metal-based reactions of relevance to catalysis. While a diverse range of these systems have been reported, they typically incorporate Lewis acids with linker units to the metal coordinating atom. This can both introduce the potential for chelation of the Lewis acid to the metal (via the formation of 5- or 6-membered chelate rings), and can make it challenging for the acid to assist transformation near the metal center. We describe here the synthesis of new Lewis-acid tethered phosphino-imines and pyiridine-imines. 'Their coordination to palladium is

also discussed, together with their potential to generate Lewis acid tethered complexes for ligand assisted bond activation reactions.





P-22 3D Ordered Assembly of Hybrid Au-TiO2 Hollow Spheres for Enhanced Photocatalysis

Cao-Thang Dinh, Chinh-Chien Nguyen, B. Echchahed and Trong-On Do (Département de génie chimique, Université Laval)

A new type of Au-TiO2 hybrid nanostructured photocatalysts was constructed by three-dimensional ordered assembly of thin-shell Au-TiO2 hollow nanospheres. The designed materials exhibit not only a high surface area but also photonic behavior originating from periodic macroscopic voids from both the inside and the outside of the very thin shell hollow spheres. The multiple-light scattering and slow photon effects resulting from this unique architecture greatly enhance the surface plasmon resonance of Au nanoparticles. As a result, these photocatalyts exhibit a several times higher photocatalytic activity compared to conventional Au-TiO2 hybrid nanopowders in the decomposition of volatile organic compounds (VOCs) under visible light illumination, and have a high potential in environmental applications.

P-23 A biomimetic synthesis of lignan natural products utilizing an oxidative cyclobutane fragmentation

Anna Albertson and Jean-Philip Lumb (Department of Chemistry, McGill University)

While lignans comprise a vast array of highly oxygenated, biologically active natural products, their biosynthesis starts from relatively simple propenyl phenols. Attempts to mimic the biosynthetic oxidative coupling of these phenols have suffered from poor regio- and chemoselectivity, precluding their application in synthesis. Here we report a novel, biomimetic approach that relies on an oxidative cyclobutane opening to intercept a key biosynthetic intermediate. We demonstrate the utility of this strategy in a concise synthesis of the natural product tanegool.

P-24 Mechanistic Studies on the Copper-Catalyzed Aerobic Oxidation of Phenols

Mohammad S. Askari,1 Jean-Philip Lumb,2 Xavier Ottenwaelder*1 (1 Department of Chemistry and Biochemistry, Concordia University,

2 Department of Chemistry, McGill University) Copper-catalyzed aerobic oxidation of phenols is an attractive green method for the conversion of the abundant phenols into versatile quinones. Here, we present our mechanistic studies on the copper-catalyzed oxidation of phenols to ortho-quinones recently reported by the Lumb group [1]. Our studies support a biomimetic pathway in which oxygen is activated by two Cu ions to form a dinuclear side-on peroxo complex, which transfers an oxygen atom to a bound phenolate, resulting in a Cu(II)-semiquinone complex. Based on the intermediates observed we propose a mechanistic cycle and support it by low-temperature stopped-flow kinetic studies.





P-25 Catalytic Oxidation of Phenols with Molecular Oxygen and Cu(II) Complexes

Andrew Proppe1, Mohammad S. Askari,1 Jean-Philip Lumb,2 and Xavier Ottenwaelder1

(1 Department of Chemistry and Biochemistry, Concordia University, 2 Department of Chemistry, McGill University)

Preparation of ortho-quinones often requires stoichiometric amounts of oxygen-atom donors and produces a significant amount of by-products. Performing the reaction catalytically using molecular oxygen has been restricted to the use of reactive metal complexes such as copper(I), akin to the copper-containing enzyme tyrosinase that oxygenates tyrosine to dopaquinone in melanin biosynthesis. Here, we report on the efficient aerobic oxidation of phenols to substituted ortho-quinones using simple and air-stable Cu(II) precursors. Easy set-up and efficiency of this reaction offers an attractive method for the oxygenation of phenols and a practical stepping stone for further functionalizations.

P-26 Biomimetic Cryptands for Investigating Cu/O2-Mediated C–H Bond Functionalizations

Laura Chaloner and Xavier Ottenwaelder ( Department of Chemistry and Biochemistry,Concordia University)

Understanding C–H bond hydroxylation mechanisms that mimic those of monooxygenase enzymes can lead to new synthetic methods for C–H bond oxidations. They would involve standard oxidants like O2 or H2O2, produce water as the only byproduct, and employ the less toxic copper metal catalyst. Here, we report on the formation of a Cu(II)-hydroperoxo species with a biomimetic coordinating cryptand and its hydroxylation behaviour. A combination of mass spectrometry, low-temperature stopped-flow experiments and kinetic studies provided evidence for the hydroxylation mechanism and how it is influenced by second coordination sphere features. L. Chaloner, M.S. Askari, A. Kutteh, S. Schindler, X. Ottenwaelder, Eur. J. Inorg. Chem. 2011, 4204-4211.

P-27 Stability of Aqueous Amine Solutions to Thermal and Oxidative Degradation in the Absence and the Presence of CO2

Francis Bougie and Maria C. Iliuta (Département de génie chimique, Université Laval)

The increase of CO2 emissions represents an important environmental issue. CO2 capture by aqueous amine solutions is today’s best available technology. Amine solutions should have good resistance to degradation as this phenomenon produces amine losses and cause the release of environmentally harmful by-products. We recently proposed the blend of 2-amino-2-hydroxymethyl-1,3-propanediol (a sterically hindered alkanolamine) and piperazine (a secondary diamine activator) as a potential absorbent. The main objective of this work is to evaluate its stability to degradation under various experimental conditions.





P-28 Synthesis of Thienoisoquinolines through One-pot Tandem Pd-catalyzed Decarboxylative Cross-Coupling and C-H Activation

Fei Chen, Nicholas W. Y. Wong and Pat Forgione ( Department of Chemistry and Biochemistry,Concordia University)

Carbon-Carbon bond forming reactions are critical in the synthesis of thienoisoquinolines that are precursors of anti-inflammatory drugs. With increased emphasis on atom economy and green chemistry, environmentally-friendly reactions such as Pd-mediated decarboxylative and C-H activation cross-couplings have gained increased attention. We developed an efficient synthetic procedure for aryl-substituted thienoisoquinoline systems using Pd-catalyzed intramolecular decarboxylative cross-coupling followed by direct C-H arylation in one-pot. Compared to previously reported synthesis, our method provides 5-fold higher yields while minimizing solvent use and chemical waste.

P-29 Cofactor-dependent Enzyme Immobilization for Organic Synthesis Reaction using Cofactor Regeneration System

Atieh Bahrami, Alain Garnier, Faical Larachi and Maria C. Iliuta (Département de génie chimique, Université Laval)

Cofactor-dependent enzymes play key roles in many organic synthesis reactions while their requirement for expensive cofactor limits their use. Furthermore, low operational stability, and difficult recovery and reuse of these enzymes restrict their industrial application. Enzyme immobilization can increase their stability and facilitate their reuse and recovery. Recently, considerable efforts have been put on cofactor regeneration to decrease the enzymatic process cost. This research focuses on the development of enzyme immobilization on magnetic nanoparticles with in-situ cofactor regeneration for the production of biobased monomers.

P-30 Single-Stage Production of High-purity Hydrogen by Sorption-Enhanced Steam Glycerol Reforming

Ion Iliuta, Hamid Radfarnia and Maria C. Iliuta (Département de génie chimique, Université Laval)

The sorption-enhanced steam glycerol reforming, an integrated process involving catalytic steam reforming of glycerol and in-situ CO2 removal, was numerically investigated in a fixed bed reactor, highlighting the effect of key operating parameters on the process performance. For CO2 removal, a new Ca-based sorbent material was recently developed in our laboratory from abundant natural limestone and the sorption kinetics was studied experimentally and described by a mathematical reaction-rate model. This integrated process offers a promising alternative for single-stage production of high purity hydrogen.





P-31 New Multifunctional MOF-5 for Separation of CO2 from Gas Mixtures Marziehossadat Shokrollahi Yancheshmeh, Trong-On Do and Maria C.

Iliuta (Département de génie chimique, Université Laval)

CO2 separation is an important industrial process for treatment of flue gas, sweetening of natural gas, and upgrading of synthetic gas and synthetic biogas. The aim of our research is to develop multifunctional MOF-5 for CO2 removal from multicomponent gas streams. Multifunctional MOF-5 containing different functionalities in one phase are synthesized and the effect of each functional group on CO2 adsorption/desorption properties is investigated. Experimental tests are performed at different temperatures, pressures and gas compositions, in order to optimize the process operation conditions.

P-32 Single Molecule Studies of Ketone Hydrogenation and Alcohol Dehydrogenation Steps, and Chiral Pocket Sampling, on a Platinum

Surface. Yi Dong, Yang Zeng, J. Boukouvalas and Peter McBreen

(Département de chimie, Université Laval)

Variable temperature scanning tunneling microscopy (STM) studies were performed on on the hydrogenation of Ph-CF3CO and the dehydrogenation of Ph-CF3CHOH on the Pt(111) surface, both in the presence and in the absence of chiral modification of the surface. It will be shown that the STM measurements isolate elementary reaction steps. Fast-scan STM studies reveal information on the dynamics of chiral pocket sampling by individual molecules.

P-33 Zinc-Catalyzed Simmons-Smith Reaction: Access to Various 1,2,3-Substituted Cyclopropanes

Éric Lévesque, Sébastien R. Goudreau and André B. Charette (Département de chimie, Université de Montréal)

The Simmons-Smith reaction is a powerful method to access complex cyclopropanes. The typical procedure involves treating an alkene with several equivalents of a pre-generated zinc carbenoid. The drawbacks of such a procedure include solubility issues, handling of air-sensitive organozinc compounds in large amounts and the generation of metalcontaining waste. This work exploits the high reactivity of aryldiazomethanes towards zinc halides to generate aryl-substituted zinc carbenoids in-situ. The procedure allows the use of a catalytic amount of zinc reagent to arylcyclopropanate various alkenes, including unactivated styrene derivatives.





P-34 Synthesis of 1,2,4-Triazoles via the Addition of Hydrazides to Secondary Amides

William S. Bechara, Inna Khazhieva, Elsa Rodriguez, and André B. Charette

(Département de chimie, Université de Montréal)

The 1,2,4-triazole core is an important motif that has attracted significant interest in the fields of medicinal chemistry and materials science. Nevertheless, this motif belongs to a class of heterocycles whose biological and physical properties remain unexplored thoroughly. Therefore, the development of efficient and practical methods for the synthesis of 1,2,4-triazoles remains a valuable target for organic chemists. Herein, we describe a general methodology that resides on the chemoselective activation of the secondary amides (1) with triflic anhydride, allowing the facile addition of readily available hydrazides (3) for the expedient synthesis of 1,2,4-triazoles (6).

P-35 Investigation of Tricarbonyl Rhenium(I) N-Heterocyclic Carbene Complexes as Potential PhotoCORMs

Nurshadrina Akabar1, Garry S. Hanan2 and Massimilliano Massi1* (1 Department of Chemistry, Curtin University, Australia

2Département de Chimie, Université de Montréal) There has been extensive research on the luminescent properties of tricarbonyl rhenium diimine complexes. However, there have been few reports on the investigation of rhenium complexes bearing cyclometalating ligands, such as N-heterocyclic carbenes (NHC). The focus of this research is to investigate the photochemical and photophysical properties of Re(I)-NHC complexes in view of their application as potential photoinducible CO releasing molecules (CORMs). In addition, the aim is to develop Re(I)-NHC complexes that release CO through an external trigger such as light irradiation. The synthesis and characterisation of a series of cationic Re(I)-NHC complexes will be presented.

P-36 Arylation of Nucleophiles Without Metal Catalysts Martin Pichette Drapeau,a,b Thierry Ollevier,a and Marc Tailleferb

(a Département de chimie, Université Laval, b Institut Charles Gerhardt Montpellier, ENSCM)

Metal-catalyzed arylation reactions are ubiquitous in synthetic organic chemistry, for example in the syntheses of diaryl ethers. New metal-free conditions will be presented, with a focus on using aryl halides in these transformations. For the arylation of phenols, we also became aware that theoretically determining the experimental frontier between nucleophilic aromatic substitution and metal-catalyzed processes is harder than what is generally thought.1 1 Pichette Drapeau, M.; Ollevier, T.; Taillefer, M. Chem. Eur. J. 2014, doi:10.1002/chem.201304164





P-37 Hydroxyamidine/ α-Aminonitrone (AMOX) Ligands Towards Luminescent Metallopolymer For Light Emitting Devices Applications Mathieu Leblanc, Mihaela Cibian, and Garry S. Hanan

(Université de Montréal, Département de Chimie)

N,N’-Disubstituted hydroxyamidines, also known as α-aminonitrones (AMOXs), display high steric and electronic modularity, as a wide range of substituents can be introduced on the α- carbon and/or on the nitrogen atoms. Hence, they afford precise electronic tunability, facilitated by the delocalization on the amidine backbone. They are excellent bidentate ligands that form stable 5-membered rings with metal ions. In our research, we exploit these properties by investigating their incorporation into supramolecular assemblies based on coordination chemistry and/ or hydrogen bonding. The type of assembly is induced by the coordination geometry of the metal ion, in combination with the coordination vectors of the ligand (e.q.: tetrahedral metal + parallel coordination vectors = grid type assembly).

P-38 On the Mechanism of Phosphine-Borane Mediated Reduction of CO2 to Methanol

Marc-André Courtemanche, Marc-André Légaré, Laurent Maron and Frédéric-Georges Fontaine

(Département de chimie, Université Laval) Carbon dioxide is a green-house gas and one of the most important contributors to global warming. Being able to generate methanol, a very efficient energy vector, from carbon dioxide is a highly desirable target for nations to be independent from fossil fuels. We recently reported a highly selective catalyst for the hydroborane (notably HBcat and high hydrogen content BH3.SMe2) mediated reduction of CO2 to species that can be readily hydrolysed to methanol. TOF reaches up to 853 h-1 and TON are >2950. In this work the mechanism was studied computationally, showing that in contrast to traditional FLP reactivity, this systems efficiency is based on the synergistic activation of both CO2 and the reducing hydroborane.

P-39 New Materials for the Green Extraction of Lanthanides Ambreen Mushtaq, Justyna Florek, Frédéric-Georges Fontaine, Dominic

Larivière, Freddy Kleitz (Département de chimie, Université Laval)

The highly pure rare earth (REE) are used in numerous advanced technologiesi, thus increasing their global demand. Industrially, REEs purification involves multiple liquid-liquid extraction steps, because of their similar complexation properties. We are proposing a greener approach or the extraction of REEs. We have developed new ligands that selectively extract specific REEs and have immobilized them on KIT-6 (hybrid porous materials)ii . These materials show enhanced selectivity towards REEs, higher degree of reusability and minimal waste production. i P. Maestro, D. Huguenin, J. Alloys Compd. 1995, 225, 520. ii J. Florek, F. Chalifour, F. Bilodeau, D. Lariviere, F. Kleitz, Adv. Funct. Mater. 2014, DOI: 10.1002/adfm.201303602





P-40 Synthesis of Highly Functionalized Organobismuthanes and Use in Arylation Reactions

Pauline Petiot, Alexandre Gagnon (Département de chimie, Université du Québec à Montréal)

Our group has developed in recent years a portfolio of reactions to form C-C, C-N and C-O bonds through organobismuthanes. These organometallic complexes are synthesized from the corresponding organomagnesium reagent, can be derivatized and coupled to any type of functionalized electrophiles or nucleophiles. Indeed, interest for organobismuthanes is growing because they tolerate most functional groups, do not require specific reaction conditions and are stable in air and moisture. In this presentation, our latest results on the preparation of highly functionalized organobismuthanes by functional group manipulation on the organometallic species will be presented. The use of these functionalized reagents in the development of new methodologies will be illustrated.

P-41 Metallic complexes of hydroxyamidinate/α-aminonitrone ligands and their application in supramolecular systems for solar energy conversion Mihaela Cibian, Sophie Langis-Barsetti, Kamrul Hasan, Daniel Chartrand

and Garry S. Hanan (Département de chimie, Université de Montréal)

Metallic complexes of hydroxyamidinate/ α -aminonitrone (AMOX) ligands were synthesized and fully characterized. Their spectroscopic and electrochemical properties were studied, in order to determine their potential for application in spuramolecular systems for solar energy conversion. Three principal research directions are aimed: 1) photocatalysis for hydrogen production; 2) electron transfer/ redox mediators in DSSC; 3) multi-metallic systems for light harvesting and energy transfer. The results of these investigations are reported herein.

P-42 Selective arylation of aniline carbamates : a versatile and removable new directing group for Pd(II)-catalyzed C-H activation

Nick Uhlig and Chao-Jun Li (Département de chimie, Université de Montréal)

The aniline carbamate, a new removable directing group for C-H activation, is introduced. Its versatility and ability as a directing group is demonstrated by its use in the ortho-arylation of a wide variety of aniline derivatives under palladium(II) catalysis, with iodonium salts as simultaneous aryl donors and oxidants. Water was found to be necessary for the reaction to achieve good yield. New selectivity was also observed, and labeling and kinetic experiments elucidate the mechanism of this transformation, showing an alternate mechanism to those seen for other substrates.2 Multiple functionalizations are shown to be possible in a controlled manner, and the directing group can be easily removed by a variety of methods, making it a valuable addition to the field of removable directing groups..





P-43 Cellulose nanocrystals (CNCs) as supporters, reducers and chiral inducers Madhu Kaushik and Audrey Moores

(Department of Chemistry, McGill University) The cellulose nanocrystals (CNCs) have been declared as the sustainable materials of choice for the 21st century.1 We exploit it for synthesizing CNC-hybrid composites, which integrate metal nanoparticles onto CNC surfaces, and their applications in heterogeneous catalysis. In addition, we also work on improving characterization techniques of CNCs to better understand its properties as a catalytic support.2 (1)Michael T. Postek, R. J. M., Alan W. Rudie, Michael A. Bilodeau Production and Applications of Cellulose Nanomaterials; Technical Association of Pulp and Paper Industry, TAPPI: Peachtree Corners, GA, August 01, 2013. (2)M. Kaushik, W. C. C., T. G. M. van de Ven, A. Moores Nordic Pulp and Paper Research Journal 2014, 29.

P-44 Hydroxyamidine (AMOX) and N-acylamidine Ligands and their Complexation with Cobalt(II) ions

M.a Carolina Chaves, Tayline Medeiros, Mihaela Cibian and Garry S. Hanan

(Département de Chimie, Université de Montréal)

Complexes of cobalt(II) are promising catalysts for hydrogen production in homogeneous photocatalytic systems. Therefore, we are interested in synthesizing new cobalt(II) complexes based on AMOX and N-acylamidine ligands, and test their performance in this type of systems. Herein, the synthesis and characterization of the ligands are showed. Amidine precursors are used for preparing both AMOXs and N-acylamidines. Generally, the amidines are prepared in good yields (60-90%) from carboxylic acids and anilines, using polyphosphoric acid trimethylsilyl ester (PPSE). The desired AMOX and N-acylamidine ligands are subsequently obtained, by N-oxidation, and respectively N-acylation of parent amidines. The ligands are characterized by NMR spectroscopy and mass spectrometry. Their complexation with cobalt(II) ions is also presented.

P-45 Adsorptive Removal of Ammonium Cations from Aqueous Solutions using Arene- and Propyl-sulfonic Acid Functionalized Mesoporous Silica

Materials Romuald Brice Babou Kammoe, Khaled Belkacemi and Safia Hamoudi

(Department of Soil Sciences and Agri-Food Engineering, Université Laval) To counter environmental threats to the water resources polluted by NH4

+, which is common in wastewaters and agricultural runoff, adsorption using mesoporous functional materials represents a promising alternative to existing treatment methods. In this study, adsorption of NH4

+ ions from aqueous solutions was investigated on arene- and propylsulfonic acid functionalized SBA-15 mesoporous silica materials. The objectives pursued were (i) synthesis and characterization of the adsorbents and (ii) comparative investigation of the effect of the operating conditions on the adsorption performance of the synthesized adsorbents.





P-46 Highly active well-defined methyltrioxorhenium heterogeneous catalyst for functionalized olefin metathesis, supported on efficient

ordered hexagonal mesoporous alumina Abdelnasser Abidli*1, 2, 3, Safia Hamoudi1, 3, Khaled Belkacemi1, 2, 3

(1Department of Soil Sciences and Food Engineering; 2Department of Food Sciences and Nutrition; 3Centre de Recherche en Catalyse et Chimie Verte

C3V, Université Laval)

Methyltrioxorhenium (MTO) based metathesis heterogeneous catalyst reported in our earlier work1 shows high activity and functional group tolerance for both methyl oleate2 and triolein3 self-metathesis. MTO was supported on worm-whole like mesoporous alumina with amorphous framework structure. However, selectivity and stability against air, moisture and heat are still challenging due to the lack of a stable well defined active single site. Therefore, MTO is supported on well ordered hexagonal alumina, to enhance metathesis active sites accessibility to improve activity, and ensuring regular mass transfer phenomena to increase selectivity by uniform pore size distributions.

P-47 Novel heterogeneous biocatalyst for galacto-oligosaccharides biosynthesis using Aspergillus oryzae β-Galactosidase immobilized on

different silica-based materials

Zeineb Ben Rejeb*1, 3, Abdelnasser Abidli1, 2, 3, Safia Hamoudi1, 3, Khaled Belkacemi1, 2, 3

(1Department of Soil Sciences and Food Engineering; 2Department of Food Sciences and Nutrition; 3Centre de Recherche en Catalyse et Chimie Verte

C3V, Laval University)

Galacto-oligosaccharides are successfully synthesized through transgalactosylation of lactose as donor and sucrose as acceptor, using Aspergillus oryzae β-galactosidase, cross linked with glutaraldehyde into seven different silica materials as novel biocatalysts. Materials have pore sizes ranging from 7 to 24 nm, with different porous shapes. These differences in textural/morphological properties affected greatly the enzyme immobilization as well as the bioconversion. Most materials exhibited good activity. However, silica foam showed the highest yield up to 86%, exceeding that of free enzyme. These biocatalysts preserved more than 75% of their activity after five successive cycles.





P-48 Homogeneous iron-catalysts for the epoxidation of olefins and C-C cross coupling

K. Hasan and C. M. Kozak

(Centre for Green Chemistry and Catalysis, Department of Chemistry Memorial University of Newfoundland)

Iron-catalyzed reactions are being rediscovered as useful tools for organic

synthesis. Research in our group explores the use of iron compounds for C-C cross-

coupling catalysis and epoxidation of olefins using aqueous hydrogen peroxide as

terminal oxidant. New Fe(III) complexes bearing tetradentate amine-bis(phenolate)

ligands are catalysts for cross-coupling of aryl Grignards with unactivated alkyl halides,

including secondary alkyl chlorides. Iron salts can be used to convert alkenes to epoxides

using hydrogen peroxide as terminal oxidant. H2O2 is an excellent choice of oxidant

because it has a high oxygen content per molecule (second only to oxygen, O2, itself),

can be cheaply made, generates water as a by-product, and can be used under relatively

dilute conditions. We have found that by using a simple combination of iron salt, basic

co-catalyst and judicious choice of solvent and temperature, good to excellent yields of

epoxide products may be obtained from a large variety of olefinic substrates. The

synthesis and characterization of new iron complexes bearing amine-bis(phenolate)

ligands will be discussed, as well our recent successes in using these compounds or

simple iron salts for C-C bond forming reactions and epoxidations.

Centre en chimie verte et catalyse - McGill...

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