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61.
Kohki Ebitani Masaki Kato Ken Motokura Tomoo Mizugaki Kiyotomi Kaneda 《Research on Chemical Intermediates》2006,32(3):305-315
Montmorillonite-enwrapped titanium hydroxide species (Ti4+-mont) acted as a highly efficient heterogeneous acid catalyst for the acylation of aromatic compounds with acid anhydrides
or carboxylic acids. The catalytic activity of the Ti4+-mont was higher than those of other acid catalysts such as zeolites, SO
4
2−
/ZrO2 and p-toluenesulfonic acid. For example, the reaction of anisole with dodecanoic acid in the presence of the Ti4+-mont catalyst gave 1-(4-methoxyphenyl)-1-dodecanone in 97% yield. Furthermore, the Ti4+-mont catalyst was easily separated from the reaction mixture and was recyclable. 相似文献
62.
Tomoo Shiomi Yasuyuki Tezuka Koji Okada Kiyokazu Imai Hisao Hayashi 《Macromolecular Symposia》1994,84(1):325-331
A two-component copolymer network comprising polystyrene (PS) and poly(dimethylsiloxane) (PDMS) as copolymer components was prepared by cross-linking PS with telechelic PDMS with a new method. The microphase structure of the dry PS/PDMS network was found to be irregular from DSC and small angle X-ray scattering measurements. The swelling behavior was observed in three kinds of mixed solvents which were chosen so as to contrast with one another in respect of solubility of the component polymers. The observed swelling degree depended on the solvent composition in a manner peculiar to the respective mixed solvent systems. The Flory swelling equation extended to the two-component polymer network qualitatively reproduced the experimental swelling behavior. 相似文献
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69.
Motokura K Nishimura D Mori K Mizugaki T Ebitani K Kaneda K 《Journal of the American Chemical Society》2004,126(18):5662-5663
Treatment of a hydrotacite, Mg6Al2(OH)16CO3, with an aqueous solution of RuCl3.nH2O afforded a monomeric Ru(IV) species on the surface of the hydrotalcite. This novel Ru-grafted hydrotalcite (Ru/HT) efficiently catalyzed alpha-alkylation of nitriles with primary alcohols through the cooperative catalysis between the Ru species and the surface base sites. The catalyst system could be further extended for the one-pot synthesis of alpha,alpha-dialkylated phenylacetonitriles via the base-catalyzed Michael reaction of alpha-alkylated phenylacetonitrile with activate olefins. 相似文献
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