Organonickel σ-Complexes—Key Intermediates of Electrocatalytic Cycles

Electrochemical reduction of nickel complexes with 2,2′-bipyridyl in the presence of ortho-substituted aromatic bromides or white phosphorus leads to the formation of highly reactive organonickel σ-complexes that are capable of selectively reacting with diverse substrates with the formation of cross-association products. Mechanisms of electrocatalytic processes involving organic halides, chlorophosphines, white phosphorus, and nickel complexes with 2,2′-bipyridyl are studied by the cyclic voltammetry and preparative electrolysis methods. Key intermediates of processes that occur in metallocomplex catalysis are determined.