• Dr. Kamlesh kumar singh

The coordination complexes of Co (II), Ni (II)) and Cu (II) were prepared from bidentate Schiff base. The Schiff base ligand were synthesized by the condensation of vanillin and 2-amino-4-chlorobenzoic acid in an alcoholic medium. The ligand and its complexes were characterized by elemental analysis, molar conductance, magnetic susceptibility measurements, solubility, infrared and ESR.The free Schiff base ligand and its metal complexes were screened for their antimicrobial activity against both Gram-positive and Gram-negative bacteria. It has been found that all the complexes are antimicrobially active and so higher activity than the free ligand. A very strong band at 1580 cm-1 is characteristics of the azomethine nitrogen present in the Schiff base ligand. This was shifted to 1545-1538 cm-1 in the complexes, which indicates the coordination of the metal to the azomethine nitrogen. The Phenolic stretching frequency of ligand does not undergo any change in the spectrum, hence the phenolic OH group does not participate in the bond formation with metals. A broad band at 2596 cm-1 ( ν COOH) is found in the ligand. This broad band is absent in all the complexes, showing the participate of carboxylate anion group in chelation. The metal-ligand found to be 1 :2 in all the complexes. The magnetic susceptibility revealed that all the complexes are paramagnetic in nature. The infrared spectra suggested that the Schiff base behaves as bidentate ligand. The molar conductivity data of the complexes in DMSO indicate they are non-electrolytes. On the basis of magnetic susceptibility and electronic spectral study, geometry of complexes was proposed to be octahedral.

Vanillin,2-amino-4-chlorobenzoic acid, metal (II) complexes, antimicrobial activity.

"Synthesis,Characterization and antimicrobial activity of Schiff base complexes derived from vanillin and 2-amino-4-chlorobenzoic acid.", International Journal of Emerging Technologies and Innovative Research (www.jetir.org), ISSN:2349-5162, Vol.6, Issue 5, page no.1733-1739, May-2019, Available :http://www.jetir.org/papers/JETIR1905T49.pdf

"Synthesis,Characterization and antimicrobial activity of Schiff base complexes derived from vanillin and 2-amino-4-chlorobenzoic acid.", International Journal of Emerging Technologies and Innovative Research (www.jetir.org | UGC and issn Approved), ISSN:2349-5162, Vol.6, Issue 5, page no. pp1733-1739, May-2019, Available at : http://www.jetir.org/papers/JETIR1905T49.pdf