Selective cleavage of Csp3–N bonds in aliphatic tertiary amines enabled by difluorocarbene to access esters and thioethers

Abstract

Presented herein is a series of C–X (X ​= ​O, S) couplings for the synthesis of esters and thioethers via difluorocarbene-promoted selective Csp³–N bond cleavage between tertiary amines and carboxylic acids or thiols. In those reactions, difluorocarbene plays an important role for generating quaternary ammonium salts and thus efficiently activates the Csp³–N bonds in aliphatic tertiary acyclic amines. The developed reaction does not require any transition metal catalyst and features broad substrate scope, good functional group compatibility and ease of execution with more than 70 examples in total.