Fe(I)-Mediated Reductive Cleavage and Coupling of CO2:  An FeII(μ-O,μ-CO)FeII Core

THF solutions of a new iron(I) source, [PhBPCH2Cy3]Fe ([PhBPCH2Cy3] = [PhBP(CH2P(CH2Cy)2)3]-), effect the reductive cleavage of CO2 via O-atom transfer at ambient temperature. The dominant reaction pathway is bimetallic and leads to the formation of a structurally unprecedented diiron FeII(μ-O)(μ-CO)FeII core. X-ray data are also available to suggest that bimetallic reductive CO2 coupling to generate oxalate occurs as a minor reaction pathway. These initial observations forecast a diverse reaction landscape between CO2 and iron(I) synthons.