Highly Regio- and Stereoselective Hydrosilylation of Internal Thioalkynes under Mild Conditions
Shengtao Ding1, Li-Juan Song, Yong Wang
1Department of Chemistry, The Hong Kong University of Science and Technology, Clear Water Bay, Kowloon, Hong Kong SAR (China).
Abstract:
A general and mild hydrosilylation of thioalkynes is described. With the cationic catalyst [Cp*Ru(MeCN)3 ](+) and the bulky silane (TMSO)3 SiH, a range of thioalkynes underwent smooth hydrosilylation at room temperature with excellent α regioselectivity and syn stereoselectivity. DFT calculations provided important insight into the mechanism, particularly the unusual syn selectivity with the [Cp*Ru(MeCN)3 ](+) catalyst. The sulfenyl group in the substrates was found to provide important chelation stabilization to direct the reaction through a new mechanistic pathway.
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