Reduction of Rhodium(III) Porphyrin Hydroxide to Rhodium(II) Porphyrin

Highly reactive rhodium(III) porphyrin hydroxides were formed from the ligand substitution of rhodium porphyrin halides in benzene and were rapidly reduced to rhodium(II) porphyrins and hydrogen peroxide. Thus hydroxide acted as the reducing agent. Oxidative addition of rhodium(U) porphyrin with hydrogen peroxide proceeded rapidly at room temperature to give back rhodium(III) porphyrin hydroxides. Rhodium(II) porphyrins and H2O2 therefore were thermally reversible with rhodium porphyrin hydroxides.