Synthesis and Structural Characterization of Schiff Base Ligand and their Metal Complexes

In the present work, the synthesis and structural characterization of a 2-phenyl3(benzamido propyl) quinazoline (3H) -4one semicarbazone/ thiosemicarbazone hydrochloride and its metal complexes have been reported. All the synthesized compounds were characterized by using various physico-chemical techniques such as Infrared spectra, electronic spectra, molar conductivity and magnetic susceptibility measurements. The ligand and metal ions reacted to form in the 2:1 ratio as found from the elemental analyses and general stiochiometry was determined, [M(PBPQS)2X2] and [M(PBPQT)2X2]; where M = Co(II), Ni(II) and Cu(II); PBPQS = 2-phenyl3 (benzamido propyl) quinazoline (3H) -4one semicarbazone and PBPQT = 2phenyl3 (benzamido propyl) quinazoline (3H) -4one thiosemicarbazone. On the basis of analytical data, a proposed structure for the Cu(II) complexes are distorted octahedral and those for Co(II) and Ni(II) complexes are octahedral. Ligands PBPQS/ PBPQT have been proposed to act in a bidentate manner co-ordinating to the metal ions though azomethine nitrogen and oxygen/ sulphur atom of either semicarbazone/ thiosemicarbazone moiety. The remaining co-ordination sites are occupied by negative ions such as Cl-, Br-, Ior NO3 -. The ligands and its metal complexes were tested for their possible antimicrobial potentials.