DFT and electrochemical study on some iron(III) complexes with 2-hydroxybenzophenones

Abstract

The synthesis, identification and electrochemical behaviour iron(III) complexes containing different 2-hydroxybenzophenone ligands are reported. The first reduction of the tris(2-hydroxybenzophenone)iron(III) complexes follow the same trend as that of the free, uncoordinated ligands and bis(2-hydroxybenzophenone)copper(II) complexes. The first reduction of the iron(III) complexes occur at a potential ca 1 V more positive than the reduction of the free ligands, but within 0.06 V of the reduction of bis(2-hydroxybenzophenone)copper(II) complexes. DFT calculations showed that [Fe(HBP)3] (where HBP = 2-hydroxybenzophenone) is high-spin. Calculations further showed that tris(2-hydroxybenzophenone)iron(III) complexes can exist as both the fac and mer isomers. DFT calculations further showed that the first reduction of the tris(2-hydroxybenzophenone)iron(III) complexes is iron based, while further reductions are ligand based.