Bimetallic Reactivity. Oxo Transfer Reactions with a Heterobimetallic Complex of Iron(II) and Vanadium(III)

Several mono- and bimetallic complexes of Fe(II) and V(III) with binucleating macrocyclic systems have been prepared. Electrochemical studies of complexes containing Fe(II) in the 6-coordinate site have shown that the Fe(II/III) potential is affected by the length of the diamine chelate in this site and by the occupancy of the open site. Oxidation of the FeII−VIII complex, A, with 2,4,6-trimethyliodosobenzene produced the FeII−VIV complex, B. Both A and B have been characterized by X-ray crystallography, cyclic voltammetry, and infrared and electronic spectroscopy. The origins of deactivation of two-metal oxidation in bimetallic complexes are discussed primarily in terms of the ligand reorganizational energy, which is called mechanical coupling.