研究者詳細 - 吉田　嘉晃

論文 - 吉田　嘉晃

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Solid phase helical and crystal structures of poly(phenylacetylene)s with para-oligo ethylene oxy methylether moieties prepared with an organorhodium catalyst in ethanol 査読有り

Mawatari Y., Yoshida Y., Motoshige A., Motoshige R., Sasaki T., Tabata M.

European Polymer Journal 57 213 - 220 2014年08月

記述言語：英語掲載種別：研究論文（学術雑誌）

The stereoregular polymerization of phenylacetylenes with a para-(ethylene oxide)-methylether: p-O(CH2CH2O)mCH3 (m = 1 and 2) using a [Rh(norbornadine)Cl]2 - triethylamine catalyst was performed at 25 °C for 0.5 h to afford the corresponding helical bright-yellow and dark-violet polymers, P1Y and P2V, respectively. The diffuse reflective UV-vis spectra of P1Y exhibited a λmax at 470 nm, unlike the broad peak of P2V. The wide angle X-ray scattering (WAXS) pattern of P1Y was assigned to the columnar hexagonal crystals (CHC)s on which the stretched cis-transoid helices of P1Y are packed. The bent position of the 2CO bond in p-O1CH22CH 2O3CH3 was deduced from these crystals. In contrast, the WAXS pattern of P2V demonstrated the formation of a CHC with contracted cis-cisoid helices. The small peak at d = 3.4 Å for P2V was assigned to a π-stacking between each benzene ring and/or helical backbone. Their stable geometrical structures, helical diameters, and bent position calculated using the MMFF94 program agreed with those estimated using WAXS. © 2014 Elsevier Ltd. All rights reserved.

DOI： 10.1016/j.eurpolymj.2014.05.010

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Structural determination of stretched helix and contracted helix having yellow and red colors of poly(2-ethynylnaphthalene) prepared with a [Rh(norbornadiene)Cl]<inf>2</inf>-triethylamine catalyst 査読有り

Mawatari Y., Motoshige A., Yoshida Y., Motoshige R., Sasaki T., Tabata M.

Polymer 55 ( 10 ) 2356 - 2361 2014年05月

記述言語：英語掲載種別：研究論文（学術雑誌）

The Rh-catalyzed polymerization of 2-ethynylnaphthalene (2EN) using ethanol or toluene solvents afforded helical poly(2-ethynylnaphthalene)s (P2EN)s, i.e., yellow-colored P2EN(Y) and red-colored P2EN(R) in good yields, respectively. The diffuse reflective UV-vis (DRUV-vis) spectra of P2EN(Y) and P2EN(R) in the solid phase showed broad absorption peaks at 445 nm and 510 nm, respectively. These helical and its crystal structures were investigated using wide angle X-ray scattering (WAXS), resonance laser Raman, and molecular mechanics calculation using MMFF94 force field. Based on these analyses, we found that P2EN(Y) was composed of stretched cis-transoid helices and P2EN(R) was composed of contracted cis-cisoid helices in which form intramolecular π-stacking by ca. 3.4 Å in distance between neighboring naphthyl rings. Furthermore, the contracted helix was energetically more stable than the stretched helix. The P2EN(Y) changed to a red-colored polymer, P2EN(Y-R), by immersion in toluene. This P2EN(Y-R) completely coincides with the P2EN(R) in its crystal structure and DRUV-vis spectrum. © 2014 Elsevier Ltd. All rights reserved.

DOI： 10.1016/j.polymer.2014.04.001

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Mutual conversion between stretched and contracted helices accompanied by a drastic change in color and spatial structure of poly(phenylacetylene) prepared with a [Rh(nbd)Cl]<inf>2</inf>-amine catalyst 査読有り

Motoshige R., Mawatari Y., Motoshige A., Yoshida Y., Sasaki T., Yoshimizu H., Suzuki T., Tsujita Y., Tabata M.

Journal of Polymer Science, Part A: Polymer Chemistry 52 ( 6 ) 752 - 759 2014年03月

記述言語：英語掲載種別：研究論文（学術雑誌）

The yellow-colored poly(phenylacetylene), Poly(Y), is obtained from phenylacetylene using a [Rh(nbd)Cl]2-NEt3 catalyst in ethanol at 25°C. The color of Poly(Y) drastically changes into red Poly(R) or reddish-black Poly(B) by immersion in acetylacetone or exposure to chloroform vapor, respectively. Poly(R) is also created from Poly(B) by contact with acetylacetone. Poly(Y) is regenerated from both Poly(R) and Poly(B) by reprecipitation from their chloroform solution into methanol. Wide-angle X-ray scattering (WAXS) patterns of Poly(Y) and Poly(R) correspond to a pseudohexagonal crystal called a columnar as stretched cis-transoid and contracted cis-cisoid helices, respectively. These helical diameters and pitch widths obtained from the WAXS measurements are agreed with those of MMFF94 calculation models. The smallest helical pitch width is 3.3 Å for Poly(R) and Poly(B). Moreover, information regarding the size and ordering of the vacant space within each polymer is estimated by using 129Xe NMR technique. © 2013 Wiley Periodicals, Inc.

DOI： 10.1002/pola.27065

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Synthesis and solid state helix to helix rearrangement of poly(phenylacetylene) bearing n-octyl alkyl side chains 査読有り

Motoshige A., Mawatari Y., Yoshida Y., Motoshige R., Tabata M.

Polymer Chemistry 5 ( 3 ) 971 - 978 2014年02月

記述言語：英語掲載種別：研究論文（学術雑誌）

Highly stereoregular polymerisations of p-n-octyphenylacetylene (pOcPA) were performed using a [Rh(norbornadiene)Cl]2-triethylamine catalyst in ethanol at -20 and 25°C to afford yellow and orange polymers, Poly(Y) and Poly(O), in yields of 64 and 99%, respectively. The XRD patterns of Poly(Y) showed a hexagonal columnar crystal with a contracted cis-cisoid helix, HexaPoly(Y)CC. The XRD pattern of Poly(O) matched that of Poly(Y) when heated to 80°C. The heat treatment of HexaPoly(Y) CC at 100°C generated two tetragonal crystals: Tetra1Poly(R)CC, containing contracted cis-cisoid helices, and Tetra2Poly(R)CT, containing stretched cis-transoid helices. The helical diameters of HexaPoly(Y)CC before and after heat treatment were estimated using XRD and were consistent with the results of MMFF 94 calculations, although the n-octyl alkyl chains of HexaPoly(Y)CC and Tetra2Poly(R)CT did not have linear alkyl chains; a bend in the chains was confirmed by 13C CP-MAS NMR. When HexaPoly(Y)CC was heated to 100°C in the solid phase, the λmax in the diffuse reflective UV-vis spectra shifted from 448 nm to 565 nm. Furthermore, the endothermic transition for HexaPoly(Y)CC occurred at 100°C in the DSC trace. Therefore, these data corroborated the assertion that HexaPoly(Y)CC thermally converted into Tetra1Poly(R)CC and Tetra2Poly(R)CT. © 2014 The Royal Society of Chemistry.

DOI： 10.1039/c3py01000g

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Synthesis and helix pitch control of π-conjugated helical polymers with accordion-like oscillation 査読有り

Yoshida Y., Mawatari Y., Tabata M.

Yuki Gosei Kagaku Kyokaishi/Journal of Synthetic Organic Chemistry 72 ( 3 ) 292 - 302 2014年01月

担当区分：筆頭著者記述言語：英語掲載種別：記事・総説・解説・論説等（学術雑誌）

Poly(alkyl propiolate)s (PAP), e.g., Poly(n-heptyl propiolate (PnHepP) and Poly((s)-2-octyl propiolate) (Ps2OctP) having an achiral or a chiral ester side chain were stereoregularly prepared with a Rh complex catalyst, [Rh(nbd Cl] 2 (nbd = norbornadiene), at 40 °C in methanol, respectively. The temperature dependence 1H and 13 C NMR spectra of PAPs and their spectral simulations indicated that the restricted rotation around the ester O-C bond takes place through the socalled 3-site jump conformation. The spectra also exhibited that the helical conjugated main-chain of Ps2OctP was largely oscillating between the sequences of contracted helix and stretched helix in the time scale of the NMRs, although the degree of the oscilation of PnHepP was fairly small compared to that of Ps2OctP. The UV-vis and IR spectra of them supported that PAPs have at least two helical conformations, i.e., contracted and stretched helices. Therefore, these spectra supported the oscillation of the helix along the main-chain axis. The proposed model calculated by MMFF94 also indicated the accordion-like helix oscillation of contracted and stretched helices (HELIOS) of PAPs which was synchronized with restricted 3-site jump rotation around the ester O-C bond in the side-chain.

DOI： 10.5059/yukigoseikyokaishi.72.292

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Contracted Helix to Stretched Helix Rearrangement of an Aromatic Polyacetylene Prepared in n-Hexane with [Rh(norbornadiene)Cl]2 -triethylamine Catalyst 査読有り国際誌

Asahi Motoshige, Yasuteru Mawatari, Ranko Motoshigea, Yoshiaki Yoshida, and Masayoshi Tabata

Journal of Polymer Science Part A: Polymer Chemistry ( John Wiley & Sons ) 51 ( 24 ) 5177 - 5183 2013年10月

Helix oscillation of polyacetylene esters detected by dynamic 1H NMR, IR, and UV-vis methods in solution 査読有り国際誌

Yoshiaki Yoshida, Yasuteru Mawatari, Asahi Motoshige, Ranko Motodshige, Toshifumi Hiraoki, Masayoshi Tabata

Polymer. Chemistry ( Royal Society of Chemistry ) 4 ( 10 ) 2982 - 2988 2013年03月

Accordion-like Oscillation of Contracted and Stretched Helices of Polyacetylenes Synchronized with the Restricted Rotation of Side Chains 査読有り国際誌

Yoshiaki Yoshida, Yasuteru Mawatari, Asahi Motoshige, Ranko Motoshige, Toshifumi Hiraoki, Manfred Wagner, Klaus Müllen, Masayoshi Tabata

Journal of the American Chemical Society ( ACS Publications ) 135 ( 10 ) 4110 - 4116 2013年02月

Irreversible Helix Rearrangement from Cis-transoid to Cis-cisoid in Poly(p-n-hexyloxyphenylacetylene) Induced by Heat-treatment in Solid Phase 査読有り国際誌

Asahi Motoshige, Yasuteru Mawatari, Yoshiaki Yoshida, Chigusa Seki, Haruo Matsuyama, and Masayoshi Tabata

Journal of Polymer Science Part A: Polymer Chemistry ( John Wiley & Sons ) 50 ( 15 ) 3008 - 3015 2012年08月

Geometrical Structures in Solution and Solid Phase of Poly(propargyl ester)s Prepared by Using a [Rh(norbornadiene)Cl]2-cocatalyst 査読有り国際誌

Yoshiaki Yoshida, Yasuteru Mawatari, Chigusa Seki, Toshifumi Hiraoki, Haruo Matsuyama, and Masayoshi Tabata

Polymer ( Elsevier Ltd. ) 52 ( 18 ) 3917 - 3924 2011年08月

Cis and trans radicals generated in helical poly(propargyl acetate)s prepared using a [Rh(norbornadiene)Cl]2 catalyst 査読有り国際誌

Yoshiaki Yoshida, Yasuteru Mawatari, Chigusa Seki, Toshifumi Hiraoki, Haruo Matsuyama, Masayoshi Tabata

Polymer ( Elsevier Ltd. ) 52 ( 3 ) 646 - 651 2011年02月

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