Synthesis, Spectroscopic Characterization and In Vitro Antimicrobial Studies of Copper (II) and Iron (III) Complexes Derived from (E)-N-Benzylidine Schiff Base Ligand

Usman B , Chindo S. Y , Amina F. H and Fa’iza I

Keywords: Antimicrobial, acetamide, benzaldehyde, spectroscopic characterization and Schiff base.


This study reported the synthesis of the novel Schiff base ligand (E)-N-benzylidieneacetamide, which was synthesized by refluxing equimolar amount of benzaldehyde and acetamide. The synthesized Schiff base was subsequently reacted with Fe(III) and Cu(II) metal salts to form the corresponding metal complexes. The compounds were characterized using FT-IR, Molar conductance measurement, Melting point and decomposition temperature studies, solubility test and in vitro antimicrobial activity studies using Agar well diffusion method against Pseudomonas aeruginosa, Eecherichia. coli and Aspergillus niger at 50, 25 and 12.5 mg/mL respectively. The spectroscopic data indicated that the Schiff base ligand acted as a bidented and coordinated to the metal via imine nitrogen and deprotonated oxygen atoms. The molar conductances were found to be 14 and 19 ohm1cm2mol-1 for the Fe(III) and Cu(II) complexes respectively, indicating that they are non-electrolytic in nature. The Schiff base have melting point of about 80 – 81OC while the complexes decomposed around 120 -150 OC. The solubility test of the compounds indicated they are most dissoluble in water, acetone, DMF and DMSO but indissoluble completely in methanol, ethanol and methylated spirit. The results of the antimicrobial studies revealed that the metal complexes exhibited better antibacterial activity than the ligand but less compared to the standard drugs (amoxicillin). Whereas, both ligand and the complexes were non active against the tested Aspergillus niger.