DOI: https://doi.org/10.55373/mjchem.v26i4.1

Keywords: Antibacterial; nickel; palladium; Schiff base; Sonogashira

Abstract

Palladium(II) and nickel(II) complexes derived from aromatic Schiff bases were synthesized and characterized through physicochemical and spectroscopic analyses, viz., melting point, elemental analysis, molar conductivity, magnetic susceptibility, FTIR, UV-Vis, and 1H and 13C NMR. The shift in ν(CN) to a lower frequency in FTIR of about 10 cm-1 indicated that complexation to Pd(II) and Ni(II) through the azomethine N was established. This was supported by the shifting of the azomethine proton signal to downfield and upfield regions in 1H NMR. In addition, the shifting of the n−π*(CN) band in the UV-Vis spectra, with Δλ = 20−47 nm, indicated involvement of the azomethine nitrogen in the complexation. Palladium(II) complexes performed better than nickel(II) complexes as catalysts in the copper-free Sonogashira reaction, with 100 % conversion of iodobenzene in 3 hours. In the antibacterial study, L1Me showed the most promising anti-MRSA and anti-MSSA activities, with both MIC and MBC values of 3 µg/ml against the tested strains. These findings highlight the potential of Pd(II) and Ni(II) complexes as catalysts and anti-microbial agents.