Two dioxomolybdenum(VI) complexes with hydrazone ligands: synthesis, characterization, crystal structures and catalytic properties

Abstract

A pair of Mo(VI) complexes, [MoO2L1(MeOH)] (1) and [MoO2L2(MeOH)] (2), where L1 and L2 are the dianions of 2-amino-N’-(3-bromo-5-chloro-2-hydroxybenzylidene)benzohydrazide (H2L1) and 2-amino-N’-(3,5-dibromo-2-hydroxybenzylidene)benzohydrazide (H2L2), respectively, have been prepared and characterized by physico-chemical methods and single-crystal X-ray diffraction. The Mo atom in each complex is coordinated by the phenolate oxygen, imino nitrogen and enolate oxygen of the hydrazone ligand, together with a methanol ligand and two oxo groups, giving a distorted octahedral geometry. The complexes proved to be effective catalysts for the oxidation of various olefins.