Cerium(IV)-Driven Water Oxidation Catalyzed by a Manganese(V)-Nitrido Complex

The study of manganese complexes as water-oxidation catalysts (WOCs) is of great interest because they can serve as models for the oxygen-evolving complex of photosystem II. In most of the reported Mn-based WOCs, manganese exists in the oxidation states III or IV, and the catalysts generally give low turnovers, especially with one-electron oxidants such as Ce-IV. Now, a different class of Mn-based catalysts, namely manganese(V)-nitrido complexes, were explored. The complex [Mn-V(N)(CN)(4)](2-) turned out to be an active homogeneous WOC using (NH4)(2)[Ce(NO3)(6)] as the terminal oxidant, with a turnover number of higher than 180 and a maximum turnover frequency of 6 min(-1). The study suggests that active WOCs may be constructed based on the Mn-V(N) platform.