"Synthesis, Spectroscopic and Biological Studies of 3d Transition Metal Complexes with Various Aniline Based Schiff Bases"

Abstract

A variety of Schiff bases and their metal complexes have been synthesized from 3 – acetyl – 2 H – chromen – 2 - one and anils. 2-hydroxybenzaldehyde was reacted with ethyl acetoacetate (acacs) in the presence of piperidine to give 3 – acetyl – 2 H - chromen – 2 - one which was further reacted with different anils namely p-toluidine, p-chloroaniline and 2-nitroanilie to obtain Schiff bases. These Schiff bases were used as ligands in the current study. Schiff base metal complexes were then synthesized by reacting Schiff base ligands with 3d-transition metals nickel( II), cobalt( II), copper( II) and zinc( II). Both ligands and metal complexes were then characterized by various spectroscopic techniques which include UV-visible spectroscopy, 1H NMR, 13C NMR spectroscopy and powder X-ray diffraction (PXRD). Stability of complexes was estimated in solid and solutions form. Amounts of metals in complexes and metals’ to ligands ratios were estimated by Atomic Absorption Spectroscopy (AAS). These metal complexes were found diamagnetic by vibrating sample magnetometry. Schiff base complexes were found to have immense applications in biological fields. So all Schiff base ligands and their metal complexes were scanned against gram positive and gram negative bacterial strains and it was found that they show promising activities against selected bacterial strains.