Synthesis, spectroscopic studies and structures of square-planar nickel(II) and copper(II) complexes derived from 2-{(Z)-[furan-2-ylmethyl]imino]methyl}-6-methoxyphenol

Two new nickel(II) [Ni(L)(2)] and copper(II) [Cu(L)(2)] complexes have been synthesized with bidentate NO donor Schiffbase ligand (2-{(Z)-[furan-2-ylmethyl]imino]methyl)-6-methoxyphenol) (HL) and both complexes Ni(L)(2) and Cu(L)(2) have been characterized by elemental analyses, IR, UV-vis, H-1, C-13 NMR, mass spectroscopy and room temperature magnetic susceptibility measurement. The tautomeric equilibria (phenol-imine. O-H center dot center dot center dot N and keto-amine, O center dot center dot center dot H-N forms) have been systemetically studied by using UV-vis absorption spectra for the ligand HL. The UV-vis spectra of this ligand HL were recorded and commented in polar, non-polar, acidic and basic media. The crystal structures of these complexes have also been determined by using X-ray crystallographic techniques. The complexes Ni(L)(2) and Cu(L)(2) crystallize in the monoclinic space group P2(1)/n and P2(1)/c with unit cell parameters: a = 10.4552(3)angstrom and 12.1667(4)angstrom, b = 8.0121(3) A and 10.4792(3) angstrom, c= 13.9625(4)angstrom and 129.6616(3)angstrom, V= 1155.22(6) angstrom(3) and 1155.22(6)angstrom(3), D = 1.493 and 1.476 g cm(-3) and Z = 2 and 2, respectively. The crystal structures were solved by direct methods and refined by full-matrix least squares to a find R = 0.0377 and 0.0336 of for 2340 and 2402 observed reflections, respectively. (C) 2009 Elsevier B.V. All rights reserved.