Dinuclear metal complexes derived from a bis-chelating heterocyclic ligand

Abstract

4,6-bis-{1-[(4,6-dichloro-[1,3,5]triazine-2-yl)-hydrazone]-ethyl-benzene-1,3-diol, C16H12N10O2Cl4 (H2-BDTD), and Co(II), Ni(II), Cu(II) and Zn(II) complexes derived from its dibasic bis-chelating form (BDTD2- or L2-) were prepared in methanol-triethylamine and characterized by MS, NMR, IR, UV-VIS and AA spectroscopic studies. Conductivities, magnetic susceptibility measurements and thermal analyses showed bis- N,N,O donor behavior of L2-. The analytical data indicate that the metal to ligand ratio is 2:1 in all the complexes. The coordination of triethylamine, water and chloride ion are observed in the Co(II), Zn(II) and Ni(II) complexes. The absence of ionizable or coordinated chloride in Cu(II) complex is a notable feature. Octahedral geometry for Co(II), Zn(II) and Ni(II) and square planar geometry for Cu(II) complexes are proposed. The paramagnetic complexes exhibit subnormal magnetic moments at room temperature (RT).