Synthesis, physicochemical and antibacterial studies of transition metal chelates involving tetradentate Schiff base

The complexes of VOIV, Mn-II, Fe-III, Co-II, Ni-II, Cu-II, Zn-II, MoO2IV and UO2IV with tetradentate Schiff base ligand derived from 2-hydroxy-5-chloroacetophenone and carbohydrazide have been prepared. These complexes have been characterized by elemental analysis, UV-Vis and IR spectroscopy, magnetic measurements and thermal analysis. The complexes were found to be quite stable and decomposition of the complexes ended with respective metal oxide as a final product. Various kinetic and thermodynamic parameters have been evaluated from the thermal decomposition data. Infrared spectral study show that the ligand behaves as dibasic tetradentate in nature in all the complexes. The solid state electrical, conductivity of these compounds has been measured in their compressed pellet form and all the compounds showed. semiconducting behaviour as their conductivity increases with increase in temperature. The Schiff base and its metal complexes have been screened for their antibacterial activity against E. coli, P. aeruginosa, S. typhi, S. aureus and B. subtilis by cup plate method. The metal complexes were shown to possess more antibacterial activity than the free ligand.