An unexpected cobalt(III) complex containing a Schiff base ligand: Synthesis, crystal structure, spectroscopic behavior, electrochemical property and SOD-like activity

Abstract An unexpected mononuclear Co(III) complex, [Co( L 2 ) 2 ·(CH 3 COO)]·CH 3 OH ( HL 2  = 1-(2-{[( E )-3,5-dichloro-2-hydroxybenzylidene]amino}phenyl)ethanone oxime), has been synthesized via complexation of Co(II) acetate tetrahydrate with HL 1 originally. The plausible reaction mechanism for the formation of quinazoline-type ligand was proposed. HL 1 and its corresponding Co(III) complex were characterized by IR, as well as by elemental analysis and UV–vis spectroscopy. The crystal structure of the complex has been determined by single-crystal X-ray diffraction. Each complex links two other molecules into an infinite 1-D chain via intermolecular hydrogen bonding interactions. Moreover, the electrochemical properties of the cobalt(III) complex were studied by cyclic voltammetry and X-ray photoelectron spectrum (XPS). In addition, superoxide dismutase-like activities of HL 1 and Co(III) complex were also investigated.