Difluorocarbene-Mediated Trimethylsilylation of Nucleophiles with HCF2N(TMS)2 as a Silylation Reagent
Hao Ruan1, Dong Zhu2, Jingwei Zhao1,3
1Key Lab of Functional Molecular Engineering of Guangdong Province, School of Chemistry and Chemical Engineering, South China University of Technology, Guangzhou 510640, China.
Abstract:
Described herein is the trimethylsilylation of various nucleophiles using a combination of HCF3 and NaHMDS. This facile protocol enables the rapid construction of alkynylsilanes, silyl enol ethers, etc., under mild conditions. Detailed mechanistic studies indicate that the trimethylsilicon intermediate formed in situ can be readily attacked by nucleophiles, with the activation of the base NaHMDS by difluorocarbene. This work first utilizes the structure of HMDS as a silicon source in the trimethylsilylation of terminal alkynes.
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