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81.
Various silacycles with vinylsilane framework are synthesized via the Lewis acid-catalyzed intramolecular hydrosilylation of alkynes. The cyclization proceeds in an endo-trans or/and in an exo-trans manner, depending on the substrate structure. This methodology is applicable to the synthesis of five-, six-, seven-, and eight-membered medium-sized silacycles. Furthermore, it is possible to obtain a silole derivative via the intramolecular hydrosilylation of the ortho-alkynyl-substituted phenylsilane 10. 相似文献
82.
Tatsuya Shono Yoshihiro Matsumura Mikiko Mizoguchi Jue Hayashi 《Tetrahedron letters》1979,20(40):3861-3864
Oxidation of secondary alcohols to ketones was accomplished by an indirect electrochemical method utilizing thioanisole as a catalytic electron carrier. 相似文献
83.
K. Mizoguchi K. Terada Y. Naito Y. Kamiya S. Tsuchida S. Yano 《Colloid and polymer science》1997,275(1):86-90
Blends of poly(ethylene-
co-5.4 mol% 3,5,5-trimethylhexyl methacrylate) (PE-TMHM) with poly(dimethylsiloxane) (PDMS) were prepared in the PDMS content
range from 0 to 20%. The miscibility was studied for PE-TMHM–PDMS blends by DSC, dynamic mechanical and microscopic spectroscopy,
and the gas permeability was measured for O2, N2 and CO2 as function of PDMS content. PE-TMHM and PDMS were partially miscible with each other below 20 wt% of PDMS content. The permeability
coefficients (P) for O2, N2 and CO2 were increased by the blending of PDMS to PE-TMHM. The change of P for O2 with PDMS content well reflected the partially miscible phase separation behavior.
Received: 10 June 1996 Accepted: 14 August 1996 相似文献
84.
Cheng Yang Gaku Fukuhara Asao Nakamura Yumi Origane Tadashi Mori Takehiko Wada Yoshihisa Inoue 《Journal of inclusion phenomena and macrocyclic chemistry》2007,57(1-4):433-437
The complexation behavior of 6-amino-6-deoxy-γ-cyclodextrin (CD), 6A,6X-diamino-6A,6X-deoxy-γ-CDs and 3A-amino-3A-deoxy-altro-γ-CD with 2-anthracenecarboxylic acid (AC) was studied by NMR, UV–vis and circular dichroism spectroscopy. These modified γ-CD derivatives were found to form stable 1:2 host-guest ternary complexes with AC in aqueous solution. Compared with native
γ-CD, the primary-face-aminated γ-CDs exhibited remarkably enhanced overall association constants as a result of the additional electrostatic interactions
between the oppositely charged host and guest. In contrast, the ternary complex formation of the secondary-face-aminated γ-CD with AC was hindered. 相似文献
85.
Kenji Mizoguchi Kiyoshi Kume Hideki Shirakawa 《Molecular Crystals and Liquid Crystals》2013,570(1):459-462
We measured a frequency dependence of ESR line width in (CH)x and (CD)x at frequencies 5~9,500 MHz. From a detailed analysis we could independently deduce 1-D diffusion rate of electron spin (neutral soliton) D‖ /c‖ 2, and the trapped spin concentration C between 200 and 340 K. 相似文献
86.
87.
[Structure: see text] The AuCl-catalyzed benzannulation of o-alkynyl(oxo)benzenes with benzenediazonium 2-carboxylate proceeds under mild conditions and a variety of anthracene derivatives, having a ketone group at the 9-position, are produced in good to high yields. The reaction proceeds most probably through the [4+2] cycloaddition between benzyne and benzopyrylium auric ate complex, which would be generated by the gold-induced electrophilic cyclization of o-alkynyl(oxo)benzenes. 相似文献
88.
89.
Hiroshi Matsui Mai Nagatori Kenji Mizoguchi 《Journal of Physics and Chemistry of Solids》2010,71(4):440-443
Temperature dependence of the complex dielectric constant at 16.3 GHz has been measured on dry poly(dA)-poly(dT) DNA with Na+ counterions under different relative humidity (RH). The rotational motion of sole water dipoles hydrated in PO2− is detected at low RH, and the collective motion due to water network in major groove is successfully observed at high RH. From the infrared (IR) spectroscopy in dry DNA introducing metallic ions (M-DNA), the symmetric and antisymmetric stretching bands of PO2− distinctly depend on RH and type of metallic ions. The IR spectral change indicates that the monovalent ions (Li and Na) are arranged in PO2− though the divalent and trivalent ions connect to the base molecules. 相似文献
90.