Direct Arene Trifluoromethylation Enabled by a High‐Valent Cu^III−CF₃Compound

Abstract

Direct CÀ H trifluoromethylation of arenes and heteroarenes poses an important synthetic challenge that is highly desirable. High-valent Cu III À CF 3 compounds have often been invoked in copper-mediated trifluoromethylation reactions, but the fundamental reactivity toward arenes is elusive. Herein, direct CÀ H trifluoromethylation of arenes/heteroarenes by a highvalent Cu III À CF 3 compound is disclosed for the first time. The Cu III À CF 3 compound serves CF 3 radical and a Cu II oxidant by homolytic cleavage of a Cu III À CF 3 bond, which engage synergistically in a S E Ar type reaction with arenes. The presence of K 2 S 2 O 8 co-oxidant can significantly improve the reaction yields. This reaction shows good efficiency, broad functional group tolerance, and the potential in late-stage functionalization. The reactivity of high-valent Cu III À CF 3 compounds disclosed in this study represents an important progress in organofluorine and Cu III chemistry.