Investigation on catecholase activity of salen Co(III) octahedral complexes

Abstract We have synthesized three octahedral Co(III) compounds in order to study their catalytic efficiency for the oxidation of 3,5-di-tertiarybutylcatechol (3,5-DTBC) into the corresponding quinone. Among the tested compounds, only one compound, 3 shows the catecholase activity. The catalytic efficiency of this compound arises from its capability to stabilise two different oxidation states of the metal centre. The initial oxidation state of cobalt ion (Co(III)) changes into Co(II) in order to accommodate the substrate. The kinetic parameters were calculated using the Michaelis-Menten equation. The catalytic loop was proposed and the byproduct formed in the cycle was experimentally determined.