Synthesis of gem -Difluoroalkenes via Cobalt-Catalyzed Defluorinative Reductive Coupling of α ‑Trifluoromethyl Alkenes

gem-Difluoroalkenes represent an important class of organic compounds, and the reductive alkylation of α-trifluoromethyl alkenes serves as a straightforward and efficient synthetic strategy to access these structures.In this work, a ligandfree reductive alkylation of α-trifluoromethyl alkenes was reported using inexpensive cobalt as the catalyst, eliminating the requirement for external supporting ligands.This transformation demonstrates excellent functional group compatibility as well as good tolerance towards heterocyclic moieties, and is compatible with primary, secondary, and tertiary alkyl halide coupling partners.A diverse array of gem-difluoroalkene products was obtained in moderate to excellent yields, and gram-scale experiments further confirm the scalability of this protocol.Overall, this cobalt-catalyzed system features the advantages of practicality and high efficiency for the construction of gem-difluoroalkenes.