Self assembled homodinuclear dithiocarbamates: one pot synthesis and spectral characterization

Several self assembled homodinuclear complexes of the type [M2(Ldtc)2·4H2O] derived from quadridentate ligand (Ldtc), where Ldtc = 2-aminobenzoylhydrazidebis(dithiocarbamate) and M = Mn(II), Fe(II), Co(II), Ni(II), Cu(II) and Zn(II) have been reported. The in situ procedure gives high yield with the formation of single product as evident by TLC and various other physicochemical techniques. Elemental analysis, TGA, (1)H NMR, (13)C NMR, ESI mass spectrometry, EPR, UV-vis. and IR spectroscopy were used to characterize the homodinuclear complexes. The spectroscopic evidences and room temperature magnetic moment values suggest that all the complexes have octahedral geometry around the transition metal atom. A symmetrical bidentate coordination of the dithiocarbamato moiety has been observed in all the complexes. The energy-minimized structure of the molecule also showed that each metal atom acquires a distorted octahedral geometry. The complexes exhibit a three-step thermolytic pattern and are non-electrolyte in nature.