Syntheses, crystal structure and biological evaluation of Schiff bases and copper complexes derived from 4-formylpyrazolone

• Two new Cu(II) complexes were synthesized and characterized.
• Single-crystal XRD of the Schiff base ligand shows it exists in amine-one form.
• Single-crystal XRD analysis of both the complexes was carried out.
• The Cu(II) complexes exist in square planer geometry.
• Antibacterial activities of Cu(II) complexes were carried out.

Two new pyrazolone based Schiff base ligands 4-((2,4-dimethylphenylimino)methyl)-4,5-dihydro-3-methyl-1-p-tolyl-1H-pyrazol-5-ol [PTPMP-ME] and 4-((3,4-difluorophenylimino)methyl)-4,5-dihydro-3-methyl-1-p-tolyl-1H-pyrazol-5-ol [PTPMP-F] were synthesized. Using these Schiff base ligands two new Copper(II) complexes, [Cu(PTPMP-ME)2] (1) and [Cu(PTPMP-F)2] (2) were synthesized. The ligands and their copper complexes were characterized by IR, 1H NMR, mass, UV–Visible spectroscopy, molar conductivity and magnetic measurement. The molecular geometry of Schiff base ligand PTPMP-ME and copper complexes were determined by single-crystal X-ray analysis. On the basis of single crystal X-ray analysis and spectroscopic techniques, square planar geometry of the complexes was proposed. The Schiff base ligands and their metal complexes were tested for antimicrobial activity against Gram-positive bacteria; Staphylococcus aureus and Bacillus subtilis and Gram-negative bacteria; Escherichia coli and Pseudomonas aeruginosa.

Two new Cu(II) complexes of pyrazolone based Schiff ligands were synthesized and found to exist in square planer geometry.Figure optionsDownload as PowerPoint slide