Nickel-Catalyzed Intermolecular Reductive Coupling of Styrene and Its Derivatives with Imines Using Methanol as a Reductant

Catalyticreductive coupling of alkenes with imines has emergedas a powerful tool for amine synthesis via C-C bond formationwith the aid of a reductant. However, many of these processes requirethe use of activated alkenes or hydrosilanes as reductants. Here,we report a nickel-catalyzed intermolecular reductive coupling ofstyrenes with imines utilizing methanol as a reductant. The key tothe success of the reaction is the introduction of MeOLi as an additive,which promotes the ring opening of the aza-nickelacycle intermediateand facilitates hydride transfer from the methoxy group to nickel.This pathway, which involves the reductive transformation of saturatedaza-nickelcycles, enables highly linear-selective reductive couplingof alkenes with imines.