SYNTHESIS AND CHARACTERIZATION OF SOME BINUCLEAR TRANSITION-METAL COMPLEXES OF A BINUCLEATING LIGAND

Five binuclear transition metal(II) complexes, [Mn(2)L(mu-Cl)Cl-2], [Fe(2)L(mu-Cl)Cl-2], [Co(2)L(mu-Cl)CI2], [Ni(2)L(mu-Cl)Cl-2(H2O)(2)] (H2O)(2) and [Zn(2)L(mu-Cl)Cl-2], were synthesized, where HL is the binucleating ligand 2,6-diformyl-4-methylphenoldi(benzoyl-hydrazone). Based on the IR spectra, elemental analyses, conductivity measurements and thermal analysis, these complexes are proposed to have an endogenous phenoxide bridge and an exogenous chloride bridge. The ligand field parameters of the nickel(II) complex were obtained from near-IR spectra. The variable magnetic susceptibility (4-3OO K) data of the manganese(II), iron(II), cobalt(II) and nickel(II) complexes indicated that the magnetic interactions between metal ions were very weak.