Dual role of BrCF2CO2Et: difluorocarbene-enabled access to α-trifluoromethyl ketones from sulfoxonium ylides†

Abstract

A transition metal and external fluorine anion-free method has been developed for the efficient trifluoromethylation of sulfoxonium ylides with BrCF₂CO₂Et to afford α-trifluoromethyl ketones. Mechanistic investigation revealed that taking advantage of the dual role of BrCF₂CO₂Et, which concurrently acts as a CF₂ and F source, is key to realizing this reaction. This method is applicable to the late-stage modification of biologically active compounds and can be readily scaled up.