Eight oxy-bridged dinuclear copper(II) complexes with catecholase-like sites, [Cu(L1)X]2 (HL1=1-diethylaminopropan-2-ol, X=N3−1, NCO−2, and NO2−3), [Cu(L2)X]2 (HL2=N-ethylsalicylaldimine, X=NO3−4, Cl−5, N3−6, NCS−7), and [Cu(L3)]2(ClO4)28 (HL3=N-(salicylidene)-N′-(2-pyridylaldene)propanediamine) have been prepared and characterized. The single crystal X-ray analysis show that the structures of complexes 6 and 8 are dimeric with two adjacent copper(II) atoms bridged by pairs of μ-oxy atoms from the L2 and L3 ligands. Magnetic susceptibility measurements in the temperature range 4–300 K indicate significant antiferromagnetic coupling for 4, 5 and 7 and ferromagnetic coupling for 6 between the copper(II) atoms. The catecholase activity of complexes for the oxidation of 3,5-di-tert-butylcatechol by O2 was studied and it was found that the complexes with the bond distance of Cu(II)⋯Cu(II) located at 2.9–3.0 Å show higher catecholase activity.
Journal of inorganic biochemistry 84(3-4), pp.171-178