Synthesis and Electrocatalytic CO2 Reduction Activity of an Iron Porphyrin Complex Bearing a Hydroquinone Moiety

An iron porphyrin complex bearing a hydroquinone moiety at the meso position was newly designed and synthesized. Electrochemical analysis revealed that it catalyzes CO2 reduction at a lower overpotential compared with an iron complex without a hydroquinone moiety. Experimental and theoretical investigation suggested that a hydroquinone moiety at the meso position stabilizes the coordination bond between the metal center and CO2 via a hydrogen bond interaction with the latter in the secondary coordination sphere.