Density functional theory analyses of bis(bipyridine)ruthenium noninnocent quinonoid and thiolosulfinato complexes containing ligands formally in the semiquinone oxidation state

Density functional theory and the polarized continuum model are used to derive the electronic structures of some open-shell, bis(bipyridine)ruthenium complexes bound to noninnocent quinonoid or thiolosulfinato ligands formally in the semiquinone oxidation state. The noninnocent properties of the o-thiolosulfinato ligand are explored and compared with those of the more conventional o-semiquinones with nitrogen, oxygen, and sulfur donor atoms. Spin densities are shown to be fairly localized in the metallocycle ring. It is demonstrated that oxidation of the parent [RuII(bpy)2 (1,2-(S,SO2)–C6H4] species occurs primarily in the metallocycle ring and is localized in the Ru–S0 bond.