Synthesis, Characterization and Anti-Microbial Studies of Metal (II) Complexes of Schiff Base Derived from Condensation of 2-Thiophene Carboxyldehyde and 2-Aminothiophenol

Schiff base ligand derived from condensation of 2-aminothiophenol and 2-thiophene carboxyldehy was synthesized and used for the preparation of Cr(II), Mn(II) and Co(II), complexes. The synthesized ligand and complexes were analyzed by decomposition temperature, solubility, magnetic susceptibility, molar conductance and infrared spectra. The decomposition temperatures of the complexes are in the range of 128-221ºC. Molar conductance values are in the range of 6.07-9.10 ohm-1cm2mol-1. New bands appeared in the IR spectra of the complexes in the range of 511-552 cm-1 and 438-473 cm-1 which indicate υ(M - N) and υ(M - S) vibrations respectively. Magnetic susceptibility measurement indicated that all complexes are paramagnetic while solubility test revealed that all complexes and ligand are soluble in DMSO. The analytical data show the formation of 2:1 metal to ligand ratio for all complexes and suggested the formula [ML2].nH2O.The ligand and metal chelates have been studied for microbial activity using well diffusion method against selected bacteria and fungi. The results signify that metal complexes inhibit more compared with Schiff base ligand against the same test organisms.