Oxygen reduction catalyzed by a water-soluble binuclear copper(ii) complex from a neutral aqueous solution.

A water-soluble binuclear CuII complex, synthesized using a polypyridine-polyamide ligand, was able to catalyze oxygen reduction to water from neutral aqueous solutions. Electrocatalytic results suggested that one CuII center was first reduced by one electron to form a CuIICuI species, which reacted with O2 to give a superoxide radical intermediate.