Electrochemical Nickel Catalyzed C(sp2)-H Functionalization of Tropones with Aldehydes

A direct electroreductive functionalization of tropones employing aldehydes as alkylating agents is reported. This C(sp2)-H functionalization process leverages the mediation of electroactive nickel complexes, enabling a wide range of both native and substituted tropones (44 examples) to be alkylated selectively at the α-position in high yields (up to 90%). Combined elec-trochemical, spectroelectrochemical and computational analyses disclosed the whole mechanistic pathway and revealed the key role played by reduced Ni complexes in activating the tropone core toward condensation with the aldehydes