Synthesis and Structural Characterization of Ni(II), Cu(II), Zn(II) and Cd(II) Complexes of Bis(2-amino-1,3,4-thiadiazole)

Abstract

In this study, the ligand bis(2-amino-1,3,4-thiadiazole) (L) has been synthesized by the reactions of oxalic acid with thiosemicarbazide. The ligand and Ni(II), Cu(II), Zn(II), Cd(II) complexes have been synthesized and its structures of these compounds have been deter-mined by elemental analysis, spectrometric and TGA/DTA, magnetic susceptibility and molar conductivity measurements. Coordination numbers of monomeric Ni(II) and Cd(II) complexes are six and four, respectively. The coordination numbers of dimeric Cu(II) and Zn(II) complexes are five and four. From the elemental analysis and mass spectral data, the complexes were proposed to have the formula [Ni(L)₂(SO₄)H₂O]·0.5DMF· 2H₂O, [Cu(L)(SO₄)H₂O]₂·DMF·2H₂O, [Zn(L)(NO₃)]₂·2NO₃·2DMF·H₂O and [Cd(L)₂]·2NO₃·1.5DMF·H₂O. Ni(II) and Cu(II) complexes are paramagnetic and non-electrolytes. The molar conductance data revealed that zinc(II) and cadmium(II) complexes are 1:2 electrolytes.