Defluorinative silylation toward a selective preparation of α-trimethylsilyl-α,α-difluoroacetates from trifluoroacetates

Abstract

Electrochemical reduction of n-hexyl trifluoroacetate 1a in MeCN, involving Bu₄NBr, TMSCl, and Et₃N using an H-type divided cell equipped with carbon plate as an anode and lead plate as a cathode at 50 °C, provided n-hexyl α-trimethylsilyl-α,α-difluoroacetate 2a in 62% yield, which is a promising precursor of an alkoxycarbonyldifluoromethyl carbanion equivalent and can be alkylated at the α-carbon by fluoride ion catalysis.

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