Ni(II), Pd(II) and Pt(II) complexes with ligand containing thiosemicarbazone and semicarbazone moiety: Synthesis, characterization and biological investigation

Abstract

The synthesis of nickel(II), palladium(II) and platinum(II) complexes with thiosemicarbazone and semicarbazone of p-tolualdehyde are reported. All the new compounds were characterized by elemental analysis, molar conductance measurements, magnetic susceptibility measurements, mass, 1H-NMR, IR and electronic spectral studies. Based on the molar conductance measurements in DMSO, the complexes may be formulated as [Ni(L)2Cl2] and [M(L)2]Cl2 (where M = Pd(II) and Pt(II)) due to their non-electrolytic and 1:2 electrolytic nature, respectively. The spectral data are consistent with an octahedral geometry around Ni(II) and a square planar geometry for Pd(II) and Pt(II), in which the ligands act as bidentate chelating agents, coordinated through the nitrogen and sulphur/oxygen atoms. The ligands and their metal complexes were screened in vitro against fungal species Alternaria alternata, Aspergillus niger and Fusarium odum, using the food poison technique.