Photochemical CO₂ Reduction to CO Catalyzed by a Doubly N-Confused Hexaphyrin Dinuclear Iron Complex

In the quest for efficient catalysts for the CO2 reduction reaction, a doubly N-confused hexaphyrin (DNCH) dinuclear iron complex, [(FeCl)2(DNCH)], was found to be catalytically active in the photochemical CO2 reduction reaction. Electrochemical and spectroelectrochemical measurements revealed that the DNCH ligand functions as a redox center in the CO2 reduction reaction. A doubly N-confused hexaphyrin (DNCH) dinuclear iron complex, [(FeCl)2(DNCH)], showed high catalytic activity for photochemical CO2 reduction using [Ru(dmb)3]2+ (dmb = 4,4′-dimethyl-bipyridine) and 1,3-dimethyl-2-aryl-2,3-dihydro-1H-benzo[d]imidazole as a photosensitizer and a sacrificial donor, respectively. Electrochemical and spectroelectrochemical measurements revealed that DNCH effectively functions as a redox center in the CO2 reduction reaction.