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Published on: June 21, 2017
Regio- and Enantioselective Cobalt-Catalyzed Sequential Hydrosilylation/Hydrogenation of Terminal Alkynes
Jun Guo1, Xuzhong Shen1, Zhan Lu1
1Department of Chemistry, Zhejiang University, Hangzhou, Zhejiang, 310058, China.
Abstract:
A highly regio- and enantioselective cobalt-catalyzed sequential hydrosilylation/hydrogenation of alkynes was developed to afford chiral silanes. This one-pot method is operationally simple and atom economic. It makes use of relatively simple and readily available starting materials, namely alkynes, silanes, and hydrogen gas, to construct more valuable chiral silanes. Primary mechanistic studies demonstrated that highly regioselective hydrosilylation of alkynes with silanes occurred as a first step, and the subsequent cobalt-catalyzed asymmetric hydrogenation of the resulting vinylsilanes showed good enantioselectivity.
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