Trifluoromethylation of (hetero)aryl iodides and bromides with copper(i) chlorodifluoroacetate complexes

Abstract

A new copper-mediated trifluoromethylation reaction using copper(I) chlorodifluoroacetate complexes as reagents is reported. The complex [L₂Cu][O₂CCF₂Cl] (L = bpy, dmbpy, phen) reacted with (hetero)aryl iodides and bromides in the presence of CsF in DMF at 75 °C to afford the trifluoromethylarenes in good to excellent yields. High compatibility with various chemical functions or (hetero)cycles was also observed in the reaction. A reaction mechanism involving a difluorocarbene intermediate, along with a subsequent formation of a –CF₃ anion was proposed.