Syntheses, crystal structures and catecholase activity of new dinuclear and cyclic trinuclear mixed valence cobalt (II, III) complexes

• Syntheses of two mixed valence Co(II,III) complexes of hydroxyl rich ligands.
• First alkoxo-phenoxo bridged cyclic trinuclear structure without oxo bridge.
• Both the complexes exhibit excellent catecholase activity.

Mixed valence cobalt (II, III) systems, one binuclear CoIIICoII (1) and another novel cyclic trinuclear CoIIICoII2 (2) complexes based on hydroxyl rich Schiff base ligands are synthesized and structurally characterized by X-ray crystallography. Catalytic activity of 1 and 2 towards oxidation of 3, 5-di-tert-butylcatechol (3,5-DTBC) to its corresponding quinone (3,5-DTBQ) are investigated in MeOH and DMF. ESI-MS technique is employed to characterize the intermediates.

Figure optionsDownload as PowerPoint slideNew dinuclear and cyclic trinuclear mixed valance complexes are developed that exhibit efficient catecholase activity. The second complex is the first structurally characterized cyclic trinuclear mixed valance cobalt complex without μ-3 bridging showing catecholase activity.