New oxovanadium(V) Schiff base complexes were successfully synthesized and characterized as potential catalytic materials for environmentally friendly oxidation processes. Two dinuclear water-soluble oxovanadium(V) complexes, [(L1H)VO(μ-O)]₂ (C1) and [(L2H)VO(μ-O)]₂ (C2), were prepared by refluxing vanadyl sulfate (VOSO₄) with the corresponding tetradentate Schiff base ligands in methanol under controlled conditions. The formation of the complexes was confirmed using several physicochemical characterization techniques, including Fourier-transform infrared spectroscopy (FT-IR), UV–visible spectroscopy, and elemental analysis, which provided evidence for the coordination of the Schiff base ligands to the vanadium center.

The catalytic performance of the synthesized complexes was evaluated in the oxidation of olefins in aqueous medium. Water was employed as a green and environmentally benign solvent in order to develop a more sustainable catalytic process. Different oxidizing agents were investigated to determine their influence on catalytic efficiency and product selectivity. The results demonstrated that the oxovanadium(V) complexes exhibit high catalytic activity toward olefin oxidation, affording excellent product yields under mild reaction conditions. Furthermore, the catalysts showed remarkable stability and recyclability, maintaining their catalytic performance over several successive reaction cycles without significant loss of activity.

These findings highlight the potential of dinuclear oxovanadium(V) Schiff base complexes as efficient and sustainable catalysts for oxidation reactions. The use of water as a solvent and the good recyclability of the catalysts make these systems promising candidates for green catalytic processes and environmentally friendly chemical transformations with potential relevance to energy-related and sustainable chemistry applications.