Magnetic and spectroscopic characterization of copper(II) chlorobenzoate adducts with substituted piperidines

1576-1581Copper(II) chlorobenzoates react with substituted piperidines in an organic medium to give solid complexes having general formula [Cu(OOCR)2(L)] (R = 2-,3- or 4 - ClC6 H4 and L = 1-methyl, I-ethyl and 2,6-dimethylpiperidine). All the complexes with copper(II) chlorobenzoates are of 1:1 stoichiometry irrespective of the amount of the ligand added and have been shown by physico-chemical methods to be binuclear, containing bidentate bridging carboxylate gmup except [Cu(OOCC6H4Cl -4 )2 (2,6-Me2 Pipd)] for which polymeric square pyramidal structure has been proposed. All the complexes show anti ferromagnetic behaviour with the exception of [Cu(OOCC6H4Cl -4 )2 (2,6-Me2 Pipd)]  which is paramagnetic. The spin exchange parameter, -2J, for two of the complexes has been evaluated from magnetic susceptibility measurements at different temperatures, which corresponds to axial binuclear copper(II) complexes with S = 1