Nickel-Catalyzed Stereoconvergent C(sp 2 )-F Alkenylation of Monofluoroalkenes.

The stereoconvergent synthesis of a single stereoisomer from E / Z -olefin mixtures remains one of the foremost challenges in organic synthesis. Herein, we describe a nickel-catalyzed stereoconvergent cross-coupling between E - and Z -mixed monofluoroalkenes and alkenyl electrophiles, which allows the construction of C(sp ² )-C(sp ² ) bonds. This defluorinative transformation offers facile access to various 1,3-dienes with E -selectivity and good functional group tolerance. Preliminary mechanistic studies indicate that the reaction most likely proceeds through a migratory insertion/β-F elimination/isomerization process.