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Updated: Jun 24, 2025
Imine Metathesis by Silica-Supported Catalysts Using the Methodology of Surface Organometallic Chemistry
Published on: October 18, 2019
Hydroboration and hydrosilylation of alkenes catalyzed by an unsymmetrical magnesium methyl complex
Xuguang Zhang1, Kai Lu1, Xi Chen1
1Department of Chemistry and Material Science, College of Science, Nanjing Forestry University, Nanjing 210037, China. mengtao@njfu.edu.cn.
Abstract:
The hydroboration and hydrosilylation of alkenes catalyzed by the unsymmetrical β-diketiminate magnesium methyl complex [(DippXylNacnac)MgMe (THF)] (1) have been reported. When complex 1 was employed as a highly efficient catalyst in the hydroboration of various alkenes with HBpin, only the anti-Markovnikov hydroboration products were obtained in high yields and with high regioselectivities under mild reaction conditions (60 °C). To our surprise, it showed different regioselectivities in the hydrosilylation of a range of alkenes with PhSiH3. Aromatic alkene substrates afforded the corresponding branched Markovnikov hydrosilylation products in high yields and with high regioselectivities; conversely, aliphatic alkenes produced the linear anti-Markovnikov products in moderate yields. This is completely consistent with the corresponding density functional theory (DFT) calculations. In addition, the practical utility was demonstrated via scale-up reactions of boronate esters and a preliminary plausible mechanism of hydroboration and hydrosilylation have been investigated as well.
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