doiSerbia

Synthesis and characterization of oxidomolybdenum(V) and dioxidomolybdeum(VI) complexes derived from isonicotinoyl(2-hydroxy-3-methoxybenzylidene)hydrazide

Nair Harikumaran M.L. (Department of Chemistry, University College, Thiruvananthapuram, India)
Thankamani D. (Department of Chemistry, University College, Thiruvananthapuram, India)

Several novel complexes of oxidomolybdenum(V) and dioxidomolybdenum(VI) were synthesized with the Schiff base, 3- methoxy salicylaldehydeisonicotinoylhydrazone (HL) derived from 3- methoxy salicylaldehyde and isonicotinoylhydrazide. The complexes were characterized by elemental analyses, molar conductance and magnetic susceptibility, as well as IR, 1H-NMR, Fmass and UV-Vis spectral studies. The complexes have the general formulae [MoO(L)XCl] and [MoO2(L)X], where X=NO3 or ClO4. The IR spectra of these complexes indicate that the ligand (HL) acts as a monoanionic tridentate chelating agent. The spectra indicate the monodentate mode of coordination for the nitrate and perchlorate groups. The X-ray diffraction studies of [MoO(L)NO3Cl] correspond to an orthorhombic crystal lattice with unit cell dimensions a = 15.49 Ả, b = 12.44 Ả and c = 10.11 Ả. All the complexes were found to have distorted octahedral geometry. Thermal studies of the complex [MoO2(L)NO3] showed that it was stable up to 240 °C, above which it started to decompose. The optimized geometry of ligand and one of its complexes, [MoO(L)NO3Cl], have been obtained by a molecular mechanics method. Antibacterial studies of the present complexes show that the oxidomolybdenum(V) complexes were more potent bactericides than the ligand and the dioxidomolybdenum(VI) complexes.

Keywords: oxidomolybdenum(V), dioxidomolybdenum(VI), 3-methoxysalicylaldehyde isonicotinoylhydrazone, thermal analysis, 3D modelling