Transition metal complexes with pyrazolone based ligand. thermogravimetric and spectroscopic studies

ABSTRACT

Transition metal complexes of Schiff base ligand [L] derived I from thiophene 2-carboxaldehyde and 4-aminoantipyrine have been synthesized to study possible structural determination for these complexes using spectroscopic and conductivity methods. Magnetic susceptibility measurements and thermal analysis were performed. Elemental analysis and conductometric titration showed the stoichiometry of the complexes. The molar conductivities of the complexes indicate that all complexes are non-electrolyte, except Ni[2+] complex behaves as 12 electrolyte and Zn[2+] complex is 11 electrolyte. Magnetic susceptibility measurements and electronic absorption spectra suggest tetrahedral geometry for CO[+2] chelate, The diamagnetic behaviour of Ni[2+] chelate indicates a square planer configuration, distorted octahedral structure for Cu[2+] chelate, Hg[2+] and Fe[3+] chelates have octahedral configuration and Zn[2+] chelate has square planar structure. Thermal studies indicate weight loss associated with water molecules. Some of the complexes show antibacterial and antifungal activities against four species of bacteria as well as four species of fungi and the results were compared with known antibiotics