Cyclometalated iridium and platinum complexes with noninnocent ligands

Studies were conducted to explore the electronic properties of the cyclometalated (C^N) complexes of iridium and platinum metals with catechol ligand. The complexes were observed to exhibit a reversible reduction of the semiquinone form to the catechol form of the ligand and an irreversible oxidation to the unstable quinone form of the ligand.