Synthesis and Physico-Chemical Properties of Some Ni(II) Complexes with Isatin-Hydrazones

摘要

New Ni(II) complexes with bioactive bishydrazones ligands based on (pyridine-2-carboxaldhyde)-3-isatin, (2-acetylpyridine)-3-isatin, and (2-benzoylpyridine)-3-isatin have been synthesized and characterized by elemental analysis, conductivity measurements, IR and UV-Vis spectroscopy, and thermal analysis. The complexes stoichiometry and formation constants have been determined. The results suggest that isatin-bishydrazones act as neutral tridentate ligands with ONN sites coordinating to the metal ion via isatin C=O, azomethine CR=N, and pyridine C=N groups to give [Ni(L)H2O]Cl2·2H2O, (L = neutral tridentate isatin hydrazone ligand).Kinetics and thermodynamic parameters of the complexes thermal decomposition have been elucidated from the thermal data using Coats and Redfern method, which has confirmed the first order kinetics.