Solid state synthesis, characterization and anti- microbial studies of some transition metal complexes of a schiff base ligand derived from parabenzoquinone and glycine

Abstract

Schiff base was synthesized by mixing parabenzoquinone and glycine mechanochemically. Its corresponding complexes of Cu, Co and Mn were synthesized by grinding metal (II) carbonates. The synthesized compound were characterized by elemental analysis, infrared spectroscopy, melting/decomposition temperature determination and conductivity measurements .
The infrared spectroscopic analysis of the ligand shows a peak at 1620cm^-1 confirm the presence of azomethane while the shift to 1602 cm^-1,1623.15cm^-1, 1635.69cm^-1 in Mn, Cu, Co complexes respectively confirmed bond formation from azo-group to metal. The melting point temperature of the ligand at 128.20^oC show that it is stable at low temperature while the decomposition temperature of Mn, Cu, Co complexes at 190⁰C,188.4⁰C,205⁰C shows that they are stable conductivity measurement shows that the complexes were found to be non-electrolytic as compared with the theoretical values. The ligand and its respective complexes showed antimicrobial activities against some bacteria and fungi at high concentrations
(1000 μg/disc and 500μg/disc) respectively while some showed no activity at all concentrations. However, Co complex shows significant activity against all the species at low concentration (250μ/disc).