Peroxidase‐like activity of an azamacrocyclic Ni(II) complex

Abstract

AbstractPeroxidase‐like activity of an azamacrocyclic Ni(II) complex, [Ni(II)(DMDAC)]2+ (DMDAC = 1,8‐dimethyl‐1,3,6,8,10,13‐hexaaza‐cyclotetradecane = 1,8‐dimethyl diazacyclam), was investigated by observing the oxidation of 2,2′‐azinobis(3‐ethylbenzothiazoline)‐6‐sulfonic acid (ABTS) in the presence of H2O2. UV/Vis and electron paramagnetic resonance spectral changes obtained from the mixture solution of [Ni(II)(DMDAC)](ClO4)2, ABTS, and H2O2 indicated that both ABTS and its oxidized form, ABTS+•, were the substrates of the peroxidase‐like activity of [Ni(II)(DMDAC)]2+. Current work and previously reported experimental and theoretical works on the peroxidase‐like activity of azamacrocyclic Ni(II) complexes suggest that these kind of macrocyclic Ni(II) complexes can generally exhibit peroxidase‐like activity in aqueous solution and the catalytic cycle proceeds through the heterolytic cleavage of the O–OH bond in a Ni(II)‐hydroperoxo species.