Synthesis, Characterization and Antibacterial Activity of Some Trivalent Transition Metal Complexes With 2-(N-Salicylideneamino)-3-Carboxyethyl-4,5-Dimethylthiophene

Varughese P. Daniel and K. Mohanan*

Department of Chemistry, University of Kerala, Kariavattom Campus, Trivandrum - 695 581, Kerala, (India)

Complexes of manganese(III), iron(III) and cobalt(III) with a Schiff base derived from 2-amino-3-carboxyethyl-4,5-dimethylthiophene have been synthesized and characterized on the basis of elemental analyses, molar conductance measurements, magnetic susceptibility data, UV-Visible, IR and proton NMR spectral studies. Manganese(III) and iron(III) complexes have been prepared by the direct reaction of the ligand and metal salt. However, the cobalt(III) complex has been prepared using [Co(NH3)5(CO3)]NO3 as synthetic intermediate. The ligand acted as monobasic tridentate coordinating through the deprotonated phenolate oxygen, azomethine nitrogen and carbonyl oxygen of the ester function and the complex has been formulated as [M(SAT)2]X, Where M = Mn(III), Fe(III) or Co(III) and X = Cl-, NO3- or OAc-. The iron(III) complex has been subjected to X-ray diffraction studies. The ligand and metal complexes have been screened for their antibacterial activity and it has been observed that the complexes are more potent bactericides than the ligands.

Mn(III), Fe(III) and Co(III) complexes, 2-(N-salicylideneamino)- 3-carboxyethyl-4,5-dimethylthiophene, X-ray diffraction, antibacterial activity.