Rhodium‐Catalyzed Defluorinative Vinylation of <i>gem</i>‐Difluoroalkenes for the Synthesis of 2‐Fluoro‐1,3‐dienes

Abstract

Summary of main observation and conclusion Herein, we present a strategy for the formation of 2‐fluoro‐1,3‐diene derivatives via rhodium‐catalyzed direct C(sp 2 )—C(sp 2 ) cross‐coupling of gem ‐difluoroalkenes and acrylamides. By merging Rh(III)‐catalyzed C(sp 2 )–H bond activation and nucleophilic addition/F‐elimination of gem ‐difluoroalkene, an efficient defluorinative vinylation reaction is uncovered, which leads to the generation of 2‐fluoro‐1,3‐dienes in moderate to good yields with excellent stereoselectivity under mild conditions. Preliminary mechanistic study suggests unique effects of fluorine substituents which allow the reactivity profile not observed with the congeners bearing heavier halides.