Synthesis,crystal structures,and catalytic oxidation properties of oxidovanadium(V) complexes with Schiff base ligands

Two new Schiff base ligands 2-chloro-N′-(5-fluoro-2-hydroxybenzylidene)benzohydrazide (H₂L^a) and 4-fluoro-2-{2-(2-hydroxyethylamino)ethylimino]methyl}phenol (HL^b) were synthesized and characterized. Their respective oxidovanadium complexes, VOL^a(OMe)(MeOH)]·MeOH (1) and VO(μ-O)L^b]₂ (2), were synthesized and characterized by spectroscopy and single-crystal X-ray diffraction. The coordination sphere of each V atom is octahedral. Both complexes showed selective heterogeneous catalytic properties with 74–98 % conversion, for the oxidation of cyclohexene, cyclopentene, and benzyl alcohol using H₂O₂ as primary oxidant.