Oxidoperoxidomolybdenum(VI) complexes involving 4-formyl-3-methyl-1-phenyl-2-pyrazoline-5-one and some β-diketoenolates

Five new oxidoperoxidomolybdenum(VI) complexes of the general composition [MoO(O-2)(fmphp)(L)], where fmphpH = 4-formyl-3-methyl-1-phenyl-2-pyrazoline-5-one and LH = acetylacetone, methyl acetoacetate, benzoylacetone, acetoacetanilide or o-acetotoluidide, have been synthesized by the interaction of [MoO(O-2)](2+) (obtained in situ during the interaction of MoO3 and 30 % H2O2 on continuous stirring at 50 A degrees C for 24 h) and the said ligands in aqueous-ethanol medium. The complexes were characterized by physicochemical analyses involving magnetic measurements, infrared, electronic, mass spectral and thermal studies. Besides applying experimental spectroscopic techniques, theoretical data calculated using density functional theory (DFT) by B3LYP/LANL2DZ have also been used for structural determination. In addition to an optimized geometry with no imaginary frequency, the computed spectral data have been found in an excellent agreement with the experimental results. Thermo-gravimetric (TG) curve was used to arrive at the insights of thermal stability of one of the synthesized complexes. From overall studies, suitable heptacoordinate pseudo-pentagonal bipyramidal geometry has been found for the title compounds.