Copper-Catalyzed Strain-Driven Enantiospecific C–C Oxidative Addition

Abstract While oxidative addition for C–C bond cleavage has been established using noble metals such as palladium and rhodium, analogous transformations with copper have remained elusive. Herein, we report a copper-catalyzed, enantiospecific cross-coupling of gem-difluorocyclopropanes with anilines that furnishes branched fluoroallylamines. Combined experimental and computational studies provide compelling evidence for the oxidative addition of a C–C bond to copper, thereby establishing a new elementary step in copper catalysis. Moreover, our findings reveal an unusual concerted substitution type reductive elimination for C–N bond formation that involves simultaneous C–F and N–H bond cleavage, bypassing conventional allylic metal intermediates and establishing a new mechanistic framework for allylation chemistry. The mechanistic principles demonstrated herein, including the pivotal C–C oxidative addition to copper and the concerted reductive elimination, pave the way for new strategies in catalytic C–C bond functionalization.