Synthesis, crystal structures and biological activity of trinuclear nickel(II) and copper(II) complexes derived from N,N'-bis(4-bromosalicylidene)-1,3-pentanediamine

Abstract

The self-assembly reaction of the bis-Schiff base N,N'-bis(4-Bromosalicylidene)-1,3-pentanediamine (H2L) with nickel chloride and sodium azide in methanol afforded a new phenolate and end-on azide bridged trinuclear nickel complex [Ni3L2(μ1,1-N3)2(CH3OH)2]2CH3OH (1). The reaction of H2L with copper acetate produced a new phenolate and acetate bridged trinuclear copper complex [Cu3L2(CH3COO)2] (2). The complexes were characterized by elemental analysis, IR and UV-Vis spectroscopy. The crystal structures of the complexes have been determined by X-ray crystallography. In complex 1, the Ni atoms are in octahedral coordination, while in complex 2, the Cu atoms are in square pyramidal and octahedral coordination. The Schiff base ligand coordinates to the metal atoms through the two phenolate O and two imine N atoms. The antimicrobial activities of the complexes were assayed and evaluated.