Tris(β-ketoiminato)ruthenium(III) complexes: Electrochemical and computational chemistry study

Abstract

The electronic and electrochemical properties are reported here for the first time for a series of five tris(β-ketoiminato)ruthenium(III) complexes. Since the β-ketoiminato ligand is unsymmetrical, both fac and mer isomers are theoretically possible for these octahedral complexes. Density functional theory calculations show that for complexes containing an H on the imino position, both the fac and mer are energetically possible, while for complexes with a Ph on the imino position, the mer isomer is energetically favoured, due to the steric hindrance caused by the Ph group in the fac isomer. Electrochemistry, utilizing cyclic voltammetry, showed RuIII/IV oxidation, RuIII/II reduction, as well as ligand based reduction of the RuII complex. Different RuIII/IV and RuIII/II redox couples were observed for the different fac and mer isomers of the tris(β-ketoiminato)ruthenium(III) complexes.