Synthesis and structural characterization of a new Schiff base macrocyclic ligand containing a piperazine head unit and its metal complexes. Crystal structure of the Co(II) complex

Abstract

A new macrocyclic Schiff base ligand, L, was synthesized by the condensation reaction of 1,4-bis(2-formylphenyl)piperazine and 1,4-diaminobutane in acetonitrile. The Schiff base ligand was characterized by elemental analysis, IR and mass spectroscopy. Three new Co(II), Cu(II) and Zn(II) complexes, [COL(NO3)]-ClO4, [CuL(NO3)]ClO4 and [ZnL(NO3)]ClO4, were prepared and characterized by elemental analysis, IR, FAB-MS, conductivity measurements and in the case of [ZnL(NO3)]ClO4 by H-1 NMR spectroscopy. The X-ray crystal structure of [CoL(NO3)]ClO4 showed that the complex contains Co(II) in a distorted octahedral geometry with an N4O2 core. Also, theoretical studies on the interaction of the nitrate ion and metal ions were carried out. (C) 2012 Elsevier Ltd. All rights reserved.