Efficient and practical protocol for silylation of hydroxyl groups using reusable lithium perchlorate dispread in silica gel under neutral condition
作者:Najmedin Azizi、Rozbeh Yousefi、Mohammad R. Saidi
DOI:10.1016/j.jorganchem.2005.11.005
日期:2006.2
for the trimethylsilylation of a wide variety of alcohols, including primary, allylic, benzylic, secondary, hindered secondary, tertiary, and phenols with hexamethyldisilazane on the surface of silica gel dispersed with LiClO4 in room temperature at few minutes in excellent yields under neutral conditions is reported. This procedure also allows the excellent selectivity under LP-SiO2 system for silylation
InCl<sub>3</sub>/I<sub>2</sub>-Catalyzed Cross-Coupling of Alkyl Trimethylsilyl Ethers and Allylsilanes via an in Situ Derived Combined Lewis Acid of InCl<sub>3</sub> and Me<sub>3</sub>SiI
作者:Takahiro Saito、Yoshihiro Nishimoto、Makoto Yasuda、Akio Baba
DOI:10.1021/jo7015289
日期:2007.10.1
Direct Csp3−Csp3 coupling of various aliphatic trimethylsilyl ethers and allylsilanes is effectively catalyzed by InCl3 and I2. The transformation is thought to involve an in situ-derived combined Lewis acid of InCl3 and Me3SiI. The reaction can be used for the construction of quaternary−quaternary and quaternary−tertiary carbon−carbon bonds. This system enabled a highly chemoselective coupling to
InCl 3和I 2有效地催化了各种脂族三甲基甲硅烷基醚和烯丙基硅烷的直接C sp3- C sp3偶联。认为该转化涉及InCl 3和Me 3 SiI的原位结合的路易斯酸。该反应可用于构建季-季和季-季碳-碳键。该系统使得能够与包括芳基卤化物部分的三甲基甲硅烷基醚进行高度化学选择性的偶联。此外,可以使用炔基三甲基硅烷和三甲基甲硅烷基乙烯酮缩醛进行偶联。
Indium Tribromide: An Efficient Catalyst for the Silylation of Hydroxy Groups by the Activation of Hexamethyldisilazane
A variety of substrates containing hydroxy groups have been protected as their corresponding trimethylsilyl ethers using 1,1,1,3,3,3-hexamethyldisilazane in the presence of indium tribromide. The catalyst indium tribromide activates the 1,1,1,3,3,3-hexamethyldisilazane and accelerates the reaction under mild reaction conditions at room temperature.
Scalable, Electrochemical Oxidation of Unactivated C–H Bonds
作者:Yu Kawamata、Ming Yan、Zhiqing Liu、Deng-Hui Bao、Jinshan Chen、Jeremy T. Starr、Phil S. Baran
DOI:10.1021/jacs.7b03539
日期:2017.6.7
A practical electrochemical oxidation of unactivated C–H bonds is presented. This reaction utilizes a simple redox mediator, quinuclidine, with inexpensive carbon and nickel electrodes to selectivelyfunctionalize “deep-seated” methylene and methine moieties. The process exhibits a broad scope and good functional group compatibility. The scalability, as illustrated by a 50 g scale oxidation of sclareolide
Ketene methyl trialkylsilyl acetals as effective silylating agents for alcohols, carboxylic acids, mercaptans, and amides
作者:Y. Kita、J. Haruta、J. Segawa、Y. Tamura
DOI:10.1016/s0040-4039(01)86575-8
日期:——
Silyl-proton exchange reactions with ketene methyl trialkylsilyl acetals proceeded rapidly and quantitatively under mild conditions. The preparative silylation of alcohols, carboxylic acids, mercaptans, and amides is described.