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41.
Suguru Motokucho Atsushi Sudo Fumio Sanda Takeshi Endo 《Journal of polymer science. Part A, Polymer chemistry》2004,42(10):2506-2511
A novel branched polycarbonate with a hydroxyl group at the chain end was synthesized by the copolymerization of glycidol with carbon dioxide (CO2). The copolymerization was carried out with 5 mol % of an alkali metal halide or quaternary ammonium salt as a catalyst under atmospheric CO2. The obtained poly(glycidol‐co‐carbon dioxide) was O‐benzoylated and O‐silylated, and the corresponding polymers were analyzed with IR, size exclusion chromatography, 13C NMR, and 29Si NMR. The IR spectroscopy analysis of the O‐benzoylated polymer revealed that the maximum incorporation degree of the carbonate group was 90% (i.e., the CO2/glycidol composition ratio was 0.9:1.0). The incorporation of CO2 as a carbonate unit was also confirmed by the treatment of this polymer with n‐butylamine, which caused the aminolysis of the carbonate and led to degraded products. © 2004 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 42: 2506–2511, 2004 相似文献
42.
Hiroyoshi Kamogawa Toshiaki Masui Suguru Amemiya 《Journal of polymer science. Part A, Polymer chemistry》1984,22(2):383-390
Reversible photocolor developments of viologens embedded in poly(N-vinyl-2-pyrrolidone) films, a typical polar aprotic solid matrix, were found to be affected by the kinds of viologen cation as well as the paired anion. The color developments in the corresponding low-molecular-weight solvents are connected closely to the solubility of viologens in these solvents; viologens are highly sensitive in the polar aprotic solvents in which they have poor solubilities, such as N-methyl-2-pyrrolidone and hexamethyl phosphoric triamide. These facts confirm the color-development mechanism consistings of electron transfer to the photoexcited viologen cation from the paired anion in polar aprotic solid matrices such as poly(N-vinyl-2-pyrrolidone). 相似文献
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47.
Youngchan Kim Dr. Kazuya Kanemoto Ken Shimomori Prof. Dr. Takamitsu Hosoya Prof. Dr. Suguru Yoshida 《Chemistry (Weinheim an der Bergstrasse, Germany)》2020,26(28):6136-6140
Catalytic thiolation and azidation of a single C−F bond of trifluoromethylarenes were achieved assisted by an ortho-silyl group with all-in-one reagents to generate a trityl cation and nucleophiles. The reactions catalyzed by ytterbium triflate efficiently afforded a wide variety of difluoromethylenes avoiding the further C−F bond cleavage, by virtue of the mild conditions without the generation of a Brønsted acid. 相似文献
48.
The inauguration ceremony of the Japan Proton Accelerator Research Complex (J-PARC) was held on 6 July 2009, celebrating the
completion of its construction. Now, the beam commissioning of the 50-GeV main proton synchrotron is in progress to improve
the beam intensity and quality. Many important experimental programs are planned with the improved beams. In this report,
some of them are introduced. 相似文献
49.
Suguru Ito 《Tetrahedron letters》2010,51(32):4243-5830
In the presence of a catalytic amount of mesoporous aluminosilicate (Al-MCM-41), both allyltrimethylsilane and silyl enol ether reacted with various acetals under mild reaction conditions to afford the corresponding homoallyl ethers and β-alkoxy ketones, respectively. The catalyst was easily recovered from the reaction mixture and could be reused in the same reaction without a significant loss of catalytic activity. Moreover, Al-MCM-41 exhibited high chemoselectivity for acetal over aldehyde in the reactions. 相似文献
50.
Kitamura T Nakaso S Mizoshita N Tochigi Y Shimomura T Moriyama M Ito K Kato T 《Journal of the American Chemical Society》2005,127(42):14769-14775
New electroactive supramolecular fibers have been formed by self-assembly of the derivatives of tetrathiafulvalene (TTF) in liquid crystals. These derivatives are designed and prepared by introducing the TTF moiety to the scaffold derived from amino acids such as L-isoleucine whose derivatives function as organogelators. These TTF-based gelators form stable fibrous aggregates in liquid crystals. These fibers are the first example of hydrogen-bonded one-dimensional aggregates having electroactive moieties whose electrical conductivities were measured after doping. Their electronic states have also been characterized by spectroscopic methods. Unidirectionally aligned fibers are formed in the oriented liquid crystal solvents on the rubbed polyimide surface for further functionalization of the fibers. 相似文献