Synthesis, characterization, crystal structures and catalytic property of copper(II) and dioxidomolybdenum(VI) complexes derived from N’-(3-bromo-5-chloro-2-hydroxybenzylidene)-4-methylbenzohydrazide

A new aroylhydrazone compound N’-(3-bromo-5-chloro-2-hydroxybenzylidene)-4-methylbenzohydrazide (H2L) was synthesized and characterized by elemental analysis, IR, 1H and 13C NMR spectroscopy. Reaction of H2L with copper bromide and bis(acetylacetonato)dioxidomolybdenum(VI), respectively, in methanol afforded complexes CuBr(HL)(CH3OH)·CH3OH) (1) and MoO2L(CH3OH) (2). Both complexes were characterized by elemental analysis and IR spectroscopy. Structures of the complexes were further confirmed by single crystal X-ray determination. The Cu atom in complex 1 is in square pyramidal coordination, with the aroylhydrazone ligand coordinating to Cu atom through phenolate oxygen, imino nitrogen and carbonyl oxygen. The Mo atom in complex 2 is in octahedral coordination, with the aroylhydrazone ligand coordinating to Mo atom through phenolate oxygen, imino nitrogen and enolate oxygen. Crystal structures are stabilized by hydrogen bonds. The dioxidomolybdenum complex shows good catalytic properties on styrene epoxidation reaction.