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211.
Yasuo Miyata Dr. Miki Terayama Takeo Minari Dr. Tohru Nishinaga Dr. Takashi Nemoto Dr. Seiji Isoda Prof. Koichi Komatsu Prof. 《化学:亚洲杂志》2007,2(12):1492-1504
Oligo(thienylfuran)s with thiophene rings at both ends ( SOSOSOS , DE‐SOSOS , DH‐SOSOS , DE‐SOSOSOS , and DH‐SOSOSOS ; S and O denote thiophene and furan rings, respectively, DE and DH denote diethyl‐ and dihexyl‐substituted, respectively) were newly synthesized by repetitive Stille coupling reactions. The UV/Vis maximum absorptions of the oligomers, SO , SOSO , SOSOS , SOSOSO , and SOSOSOS , exhibited a clear bathochromic shift with increasing number of heterocycles. The value of the oxidation peak potential (Epa1) determined by cyclic voltammetry decreased with an increase in the number of heterocycles by 0.06–0.08 V per heterocycle. The crystal‐packing structures of DE‐SOSOS and DH‐SOSOS determined by X‐ray crystallography have a herringbone motif and are denser than the reported structures of pentacene and α‐sexithiophene. The morphologies of thin films prepared by vacuum deposition and spin coating were investigated by atomic force microscopy and X‐ray diffraction. Among these films, those of DE‐SOSOS and DH‐SOSOS exhibited highly ordered arrangements. The devices based on vacuum‐deposited and spin‐coated films of DE‐SOSOS and DH‐SOSOS displayed the highest FET mobilities of 10?2–10?3 cm2 V?1 s?1 among the oligomers reported in this study. 相似文献
212.
213.
Fengyu Zhao Yutaka Ikushima Masayuki Shirai Takeo Ebina Masahiko Arai 《Journal of molecular catalysis. A, Chemical》2002,180(1-2)
The selective hydrogenation of cinnamaldehyde (CAL) was investigated using silica supported platinum catalysts in supercritical carbon dioxide. Selectivity to cinnamyl alcohol (COL) is enhanced as Pt0/Pt2+ ratio increases; namely, zero-valent metallic surface is beneficial to the formation of COL compared with less reduced surface. The influence of Pt0/Pt2+ ratio is more significant on the selectivity than on the total conversion. For the catalyst with small Pt0/Pt2+ value, the selectivity also depends on the degree of platinum dispersion. The selectivity to COL is higher for higher degree of platinum dispersion. The CO2 pressure did not affect the conversion and selectivity so much. 相似文献
214.
215.
The reactions of aryl Grignard reagents with p- and m-bromochlorobenzenes catalyzed by non-ligated NiCl2 give selectively chlorobiphenyl derivatives. By the stepwise reaction, an unsymmetrical terphenyl was synthesized in a good yield. 相似文献
216.
217.
Takeo Shirnidzu Hiroshi Segawa 《Phosphorus, sulfur, and silicon and the related elements》2013,188(1-4)
Abstract Molecular Engineering, tailor-made systematization of functional molecule is an important research subject for functional molecular materials. In principle, some of the multi-porphyrin systems are considered to be converted into the elements of molecular photo-electronic devices. Especially, their systematization with appropriate electron mediators into large polymeric systems is one of the feasible approaches to the molecular systems based on the electron transfer. Phosphorus (V)porphyrin has an unique structure, 3 centers 4 electrons, covalent bond in axial direction, and many interesting derivatives were synthesized. 相似文献
218.
219.
Tetsuo Tsuda Kazuhiro Kunisada Norio Nagahama Shohei Morikawa Takeo Saegusa 《合成通讯》2013,43(9-10):1575-1581
Ni(O)-phosphine(L) complexes (L=tri-n-alkylphosphines and bis(diphenylphosphino)butane) catalyzed the cycloaddition of ethoxyethyne and carbon dioxide to afford 4,5-diethoxy-α-pyrone regioselectively. 相似文献
220.
Tohoru Takeda Jin Wu Qingkai Huo Tetsuya Yuasa Kazuyuki Hyodo Takao Akatsuka 《Journal of synchrotron radiation》2008,15(5):528-531
Fluorescent X‐ray computed tomography (FXCT) enables visualization of myocardial fatty acid metabolism by using non‐radio‐iodinated I‐5‐(p‐iodophenyl)‐3‐(R,S)‐methylpentadecanoice acid (BMIPP). In this experiment, age‐dependent myocardial metabolic impairment was successfully imaged and analyzed quantitatively in J2N‐k cardiomyopathic hamster using FXCT. 相似文献