Cu-catalyzed hydrofluoroacetylation of alkynes or alkynyl carboxylic acids leading highly stereoselectively to fluoroacetylated alkenes

Abstract

A copper-catalyzed hydrofluoroacetylation of arylacetylenes or alkynyl carboxylic acids with bromofluoroacetates was developed. The reaction shows excellent stereoselectivity to afford fluoroacetylated alkenes in good to excellent yields with a broad substrate scope. A preliminary mechanism study suggested that a radical pathway was involved in the reaction and (phenylethynyl)copper might be the key intermediate for the reaction. B₂pin₂ also plays an indispensable role in this novel hydrofluoroacetylation reaction.