Synthesis, characterization, structures, and catalytic property of oxovanadium(V) complexes with hydrazone ligands

The reaction of [VO(Acac)(2)] with 4-methyl-N'-[(2-hydroxy-1-naphthyl)methylidene]benzohydrazide (H2L1) and 4-methyl-N'-[1-(2-hydroxynaphthyl)ethyiidene]benzohydrazide (H2L2), respectively, in methanol, affords two new oxovanadium(V) complexes [VO(OMe)L-1](2) (I) and [VO(OMe)L-2] (II). Both complexes have been characterized by elemental analysis, IR, and single crystal X-ray diffraction methods. Complex I is a methoxide-bridged dinuclear oxovanadium(V) compound, while complex II is a mononuclear oxovanadium(V) compound. The dinegative hydrazone ligands coordinate to the metal atoms through phenolate, imine, and deprotonated amide donor atoms. The geometry around vanadium atom in I is a distorted VNO5 octahedron, while that in II is a VNO4 square pyramid. Both complexes have effective catalytic property for the sulfoxidation reaction.