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

摘要

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 ?, b = 12.44 ? and c = 10.11 ?. 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.