Aryl-CF3 Bond-Forming Reductive Elimination from Palladium(IV)

This communication describes oxidatively induced Ar-CF3 bond-forming reductive elimination from new Pd-II complexes of general structure (L similar to L)Pd-II(Ar)(CF3). The electrophilic fluorinating reagent N-fluoro-2,4,6-trimethylpyridinium triflate promotes these reactions in good to excellent yields. The palladium (IV) intermediate ('Bu-bpy)Pd-IV(CF3)(F)(OTf)(C6H4F) has been isolated, characterized, and demonstrated to undergo high yielding Ar-CF3 coupling upon thermolysis. This work provides an attractive conceptual framework for the developement of Pd-II/IV-catalyzed arene trifluoromethylation reactions.