Pressure-Induced Polymerization of Dehydro [24] annulenes Derivative

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Pressure-Induced Polymerization of Dehydro [24] annulenes Derivative. Shimizu-group M1 NAKASE Tomoya. 1. Contents. ・ Introduction background about 24NHBn( Dehydro [24] annulenes derivative) example of pressure-induced polymerization ・ Experiment setting - PowerPoint PPT Presentation

Transcript of Pressure-Induced Polymerization of Dehydro [24] annulenes Derivative

Pressure-Induced Polymerization of Dehydro[24]annulenes Derivative

Shimizu-groupM1 NAKASE Tomoya

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Contents・ Introduction background about 24NHBn(Dehydro[24]annulenes derivative) example of pressure-induced polymerization ・ Experiment setting experiment – Optical observation Raman Spectroscopy Infrared Spectroscopy mass spectrometry (LDI-TOF) measure the electrical resistance Result & Discussion・ Summary

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Introduction

carbon nanotubes

・ very small size and high strength・ superior electrical and heat conductivity・ various properties from semiconductor to metal etc.

Dehydro[24]annulenes

expected polymerization

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pressureself-assembly molecule

synthesis of conjugated tubular structure

Sample : 24NHBn(Dehydro[24]annulenes derivative)collaborative research with Rubin Group (UCLA) and Tobe lab

Doesn’t polymerize by heat or UV. (so far)

→What about pressure ?

Control 24NHBn using side chain

24NHBn

Mitsuharu Suzuki, et al., ORGANIC LETTERS Vol.12, No.10, 2346-2349 (2010) 4

24NHBn on ambient pressure

Example of pressure-induced polymerization Diiodobutadiyne : 1

Poly-(diiododiacetylene) (PIDA) : 2

Control PIDA using side chain.

Christopher Wilhelm et al., J.AM.CHEM.SOC , 130 , 4415-4420 (2008) 5

Christopher Wilhelm et al., J.AM.CHEM.SOC , 130 , 4415-4420 (2008)

Previous work

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•Optical observationUsing Multi Anvil Press in cocrystals of 1 ・ 3

before pressing

3 GPa 6 GPa

•Raman Spectroscopy(A) 1 ・ 3 before pressing (B)1 ・ 3 after pressing to 2.8 GPa

(C)2 ・ 5 polymer cocrystal

Motivation

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The carbon nanotubes synthesis method has not been developed yet completely in the handling on diameter, length, bond type etc. carbon nanotubes

self-assembly molecule in crystal

synthesis of conjugated tubular structure

pressure

0 500 1000 1500 2000 2500 3000 3500 4000

Abso

rban

ce (a

rb. u

nits)

wave numbers (cm- 1)

Infrared Spectroscopy

mass spectrometry (LDI-TOF)

Electrical resistance measurement

0 10 20 300

100

200

300

400

500

Elec

trica

l res

istan

ce (G

Ω)

Pressure (GPa)

Optical observation

Experiment ~ strategy~Raman Spectroscopy

1000 1200 1400 1600 1800 2000 2200 2400 2600

Inte

nsity

(arb

.unit)

Wavenumber(cm -̂ 1)

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Electrical resistance measurement

Powder like sample

Optical observation

Sample

Insulating Layer(Alumina Powder)

Electrode(Pt)

Pressure medium(Daphne 7373, MeOH)

Gasket(SUS310s)

Pressure marker(ruby)

sample setting (DAC)

500 mm 550μm

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ambient pressure 0.49 GPa 0.66 GPa 0.82 GPa 1.07 GPaPressure medium : Daphne 7373

ambient pressure 1.26GPa 1.62GPa 1.70 GPa0.60 GPaPressure medium : MeOH

sample size: 130×50 μm2

sample size: 80×40 μm2

• Measure pressure medium dependence

The color change depends on the pressure medium.This result supports that expected polymerization will progress. 10

24NHBn

• Raman spectroscopy

1000 1200 1400 1600 1800 2000 2200 2400 2600

In

tens

ity (a

rb.un

it)

Wavenumber(cm -̂ 1)

NH

O

O

O

NH

O

O

NH

O

O

NH

O

24NHBn

0.41 GPa

before pressing

diamond

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Pressure medium : Daphne 7373

Sample after the change in color takes a different binding mode.

0 500 1000 1500 2000 2500 3000 3500 4000

Ab

sorb

ance

(arb

. unit

s)

wave numbers (cm- 1)

NH

O

O

O

NH

O

O

NH

O

O

NH

O

before pressing

after pressing(recalled sample)

24NHBn

• Infrared spectroscopy ~ supported by Prof. Mita ~

C≡C 伸縮C=C 伸縮 , C=O 伸縮

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•Mass spectrometry (LDI-TOF) ~ supported by Tobe lab ~

After applying pressure, the signals of monomer reduce.

Polymerization??

before pressing

after pressing(recalled sample)

monomer

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500 1000 1500 2000 2500 35003000 4000 4500 5000

100

100

500 1000 1500 2000 2500 35003000 4000 4500

Mass/Charge

5000Mass/Charge

ambient pressure 0.44 GPa 1.10 GPa

Ruby 18.25 GPa5.27 GPa 10.71GPa

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• Electrical resistance measurement

Summary・ 24NHBn seems to polymerize by pressure. - sample color : yellow → black - Expected polymerization will progress.

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24NHBn

Experimental method ~ Infrared Spectroscopy~

Example of pressure-induced polymerization Diiodobutadiyne : 1

Poly-(diiododiacetylene) (PIDA) : 2

Crystal structure

1・ 3 cocrystals

1 ・ 4 cocrystalstop

side

Control PIDA using side chain.

Christopher Wilhelm et al., J.AM.CHEM.SOC , 130 , 4415-4420 (2008)

Previous work of PIDA (color change)・ DACIn cocrystals of 1 ・ 3t ransparent and colorless ⇒blue and opaque (at 0.3 GPa)⇒darken to black (further pressure)

In cocrystals of 1 ・ 4t ransparent and colorless⇒distinct blue from 1 ・ 3 at a single point (at 2.8 GPa) →spread throughout the material⇒darken to black (further pressure)

※Each of the observed color change is irreversible.

Christopher Wilhelm et al., J.AM.CHEM.SOC , 130 , 4415-4420 (2008)

Previous work of PIDA (Raman Spectroscopy)

Christopher Wilhelm et al., J.AM.CHEM.SOC , 130 , 4415-4420 (2008)

(A) 1 ・ 3 before pressing (B)1 ・ 3 after pressing to 2.8 GPa

(C)1 ・ 4 before pressing (D)1 ・ 4 after pressing to 3 GPa

(E)2 ・ 5 polymer cocrystal

X-ray Diffraction Studies1 ・ 3 cocrystals→The sample still contains monomer. (to 1 GPa , blue)

→The mosaicity of the crystal is too big to prevent further analysis.

1 ・ 4 cocrystals→no evidence for polymerization (to 3 GPa , blue)

The black material (1 ・ 3 and 1 ・ 4) doesn’t diffract as a single crystal.

Pressure