Direct Arene Trifluoromethylation Enabled by a High-Valent Cu -CF Compound.

Direct C-H trifluoromethylation of arenes and heteroarenes poses an important synthetic challenge that is highly desirable. High-valent Cu -CF compounds have often been invoked in copper-mediated trifluoromethylation reactions, but the fundamental reactivity toward arenes is elusive. Herein, direct C-H trifluoromethylation of arenes/heteroarenes by a high-valent Cu -CF compound is disclosed for the first time. The Cu -CF compound serves CF radical and a Cu oxidant by homolytic cleavage of a Cu -CF bond, which engage synergistically in a S Ar type reaction with arenes. The presence of K S O 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 -CF compounds disclosed in this study represents an important progress in organofluorine and Cu chemistry.