Synthesis and Characterization of Divalent Nickel, Copper and Cadmium Complexes of N-(2-2-[1-(3-aminophenyl) ethylidene] hydrazino-2-oxoethyl) Benzamide

Complexes of Ni(II) (1), Cu(II) (2) and Cd(II) (3) with a novel Schiff base N-(2-2-[1-(3aminophenyl) ethylidene] hydrazino-2-oxoethyl) benzamide (LH) have been prepared and characterized by elemental analysis, TG-DTA, magnetic, electronic, molar conductivity measurements, IR, SEM, NMR, ESR and mass studies. It is observed that all the complexes having 1:1 metal-ligand stoichiometry are tetracoordinated. The result shows that LH binds to Cu and Cd ions through the hydrazidic carbonyl oxygen, azomethine nitrogen and amine nitrogen as a tridentate ligand while with Ni ion, it coordinates as a bidentate species through the hydrazidic carbonyl oxygen and azomethine nitrogen. The ligand exhibits keto-enol tautomerism in 2 in which it acts as a uninegative ligand. Complexes 1 and 3 behave as 1:1 electrolytes in DMF solution while complex 2, as a nonelectrolyte. Complex 2 is diamagnetic and ESR inactive which suggest that copper ion is present in its cuprous form. SEM images are used to observe external morphology of the compounds.