5-Nitro-1,10-phenanthroline bis(N,N-dimethylformamide-Κ′O)-bis(perchlorato) copper(II): synthesis, structural characterization, and DNA-binding study

Abstract

The hexa-coordinated copper(II) complex [Cu(L)(DMF)2(ClO4)2], where L = 5-nitro-1,10-phenanthroline, was synthesized and characterized. The X-ray crystal structure shows that the copper is coordinated by the two N-atoms of the 1,10-phenanthroline ligand plus four O-atoms, two from DMF ligands and two from the perchlorate anions. Thermal analysis showed that the complex was stable up to 285 °C. The interaction of the complex with calf thymus DNA was investigated using absorption and emission spectroscopic studies, and the binding constant (K b) and linear Stern–Volmer quenching constant (K sv) have been determined. Electrochemical characterization of the complex in acetonitrile showed a quasi-reversible one-electron exchange voltammogram for the Cu2+/Cu+ redox couple at ca. E 1/2 = −1.00 V (versus SCE) with ΔE = 200 mV and i pc/i pa ≈ 1.