Oxidovanadium(IV) complexes involving dehydroacetic acid and β-diketones of bioinorganic and medicinal relevance: Their synthesis, characterization, thermal behavior and DFT aspects

Six new mixed-ligand complexes of oxidovanadium(IV) of the general composition [VO(dha)(L)(H2O)], where dhaH = dehydroacetic acid, LH = β-diketones, viz., acetoacetanilide (aaaH), o-acetoacetotoluidide (o-aatdH), o-acetoacetanisidide (o-aansH), acetylacetone (acacH), methyl acetoacetate (macacH) or ethyl acetoacetate (eacacH) have been synthesized by the reaction of VOSO4⋅5H2O and the ligands given above in aqueous-ethanol medium. The resulting complexes have been characterized by spectroscopic techniques. Geometry optimizations were performed with the Gaussian 09 software package by using density functional theory (DFT) methods with Becke-3-Lee-Yang-Parr (B3LYP) hybrid exchange-correlation functional and the standard LANL2 MB basis set for dhaH and its complex, [VO(dha)(acac)(H2O)] (4). HOMO-LUMO structure with energy level diagram of complex [VO(dha)(acac)(H2O)] (4).