Electrochemically driven Nickel-Catalyzed Enantioselective Reductive Conjugate (Hetero)Arylation of Enones

Herein, we report an electrochemical nickel-catalyzed enantioselective reductive conjugate (hetero)arylation of enones in an undivided cell with low-cost electrodes in the absence of external reductants. Aryl bromides/iodides/triflates or vinyl bromides were employed as electrophilic reagents for the efficient preparation of more than 50 valuable β-arylated ketones in a simple manner (up to 97% yield, 97% ee). With the advantages of electrochemistry, excellent functional group tolerance and late-stage modification of complex natural products and pharmaceuticals made the established protocol greener and more economic. Mechanism investigation suggest that a NiI/NiIII cycle is involved in this electro-reductive reaction rather than metal reductant driven Ni0/NiII cycle. Overall, the efficient electrochemical activation and turnover of the nickel catalyst avoid the drawbacks posed by the employment of stoichiometric amount of sensitive metal powder reductants.