Synthesis and characterization of copper(II) and cobalt(II) complexes with two new potentially hexadentate Schiff base ligands. X-ray crystal structure determination of one copper(II) complex

Two new potentially hexadentate N2O4 Schiff base ligands 2-((z)-(2-(2-(2-((z)-3,5-di-tert-butyl-2-hydroxybenzylideneamino) phenoxy) phenoxy) phenylimino) methyl)-4,6-di-tert-butylphenol [H2L1] and 2-((z)-(2-(2-(2-((z)-3,5-di-tert-butyl-2-hydroxybenzylideneamino) phenoxy)-5-tert-butylphenoxy) phenylimino)methyl)-4,6-di-tert-butylphenol [H2L2] were prepared from the reaction of 3,5-di-tert-butyl-2- hydroxy benzaldehyde with 1,2-bis(2'-aminophenoxy)benzene or 1,2-bis(2'-aminophenoxy)-4-t- butylbenzene, respectively. From the direct reaction of ligands [H2L1] and [H2L2] with copper(II) and cobalt(II) salts in methanolic solution and in the presence of N(Et)(3) the neutral [CuL1], [CuL2], [CoL1] and [CoL2] complexes were prepared. All complexes were characterized by IR spectra, elemental analysis, magnetic susceptibility, mass spectra, molar conductance (Lambda(m)), UV-Vis spectra and in the case of [ CuL2] with X-ray diffraction. X-ray crystal structure of [ CuL2] showed that the complex contains copper( II) in a distorted square planar environment of N2O2 donors. Three CH/pi interactions were observed in the molecular structure of latter complex. (C) 2008 Elsevier B.V. All rights reserved.