Electrocatalytic water oxidation by a molecular cobalt complex through a high valent cobalt oxo intermediate

Biuret-modified tetraamidomacrocyclic cobalt complex [CoIII-bTAML]− is shown to catalyze electrochemical water oxidation at basic pH leading to the formation of O2. Electrochemical and spectroscopic studies indicate a high valent cobalt oxo intermediate isoelectronic to CoV(O) as the active oxidant. The kinetic isotope effect of 8.63 indicates an atom proton transfer mechanism.