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1.
Shuichi Oi Mitsutoshi MoroHiroe Fukuhara Takanori KawanishiYoshio Inoue 《Tetrahedron》2003,59(24):4351-4361
The addition of arylstannanes to the carbon-heteroatom double bond in the presence of a catalytic amount of a cationic rhodium complex ([Rh(cod)(MeCN)2]BF4) was examined. The reactions of aldehydes, α-dicarbonyl compounds, and N-substituted aldimines with the arylstannanes gave corresponding alcohols, α-hydroxy carbonyl compounds, and amines, respectively. An arylrhodium complex generated by the transmetalation with the arylstannane was probably the active catalytic species. 相似文献
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Kenichi Oyaizu Junya Katoh Fumiaki Suzuki Mitsutoshi Jikei Kimihisa Yamamoto Hiroyuki Nishide Eishun Tsuchida 《先进技术聚合物》1991,2(3):155-159
Oligo(phenylene sulfide) (OPS) containing one disulfide bond at the end of the chain, which was obtained by the oxidative polymerization of diphenyl disulfide, had a relatively low Td10%(temperature for 10% weight loss) of 412 °C because of degradation of the disulfide bond. But this thermal cleavage of the disulfide bond promoted the curing reaction through thiophenoxy radical formation. OPS was allowed to react with diiodobenzene at 220 °C. The thermal stability of OPS was improved through the consumption of the disulfide bond and the coupling of the chain. 相似文献
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A mild one-pot method for the synthesis of acyclic N-(1-methoxyalkyl)amides starting from carboxylic acids and methyl imidates had been developed and applied to the total synthesis of the insect poison pederine . 相似文献
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Kenji Miyatake Mitsutoshi Jikei Junya Katoh Kimihisa Yamamoto Hiroyuki Nishide Eishun Tsuchida 《先进技术聚合物》1994,5(4):216-220
Poly(2,5-dimethylphenylene sulfide) was prepared by oxidative polymerization of sulfur chloride with p-xylene using 2,3-dichloro-5,6-dicyano-p-benzoquinone (DDQ) as an oxidizing agent. The reaction proceeded efficiently under atmospheric pressure and at room temperature. The polymer formed had a high melting temperature and linear structure which was confirmed by spectroscopies. The effects of reaction time, solvent, temperature and oxidizing agent on polymerization are also discussed. 相似文献
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The millimeter- and submillimeter-wave spectra of the NiBr radical in the X (2)Pi(3/2) and A (2)Delta(5/2) states were observed by a source-modulated microwave spectrometer. The NiBr radical was generated in a dc glow discharge through the mixture of Br(2) vapor and Ar gas by the sputtering reaction with a Ni cathode. Observed transition frequencies were independently analyzed for both electronic states using a standard polynomial expression of a Hund's case (c) approximation. Anomalous behavior of the effective molecular constants in the X (2)Pi(3/2) state was interpreted as the result of the perturbation between the X (2)Pi(3/2) and A (2)Delta(5/2) states. The deperturbed molecular constants were derived using a simplified supermultiplet Hamiltonian including the interaction terms between the two electronic states. 相似文献
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