Syntheses, X-ray structures, and catalytic oxidations of dioxomolybdenum(VI) complexes with tridentate benzohydrazones

Abstract

Two new dioxomolybdenum(VI) complexes, [MoO₂L¹(CH₃OH)]·CH₃OH (1) and [MoO₂L²(CH₃OH)] (2), where L¹ and L² are dianionic forms of N’-(3-bromo-2-hydroxybenzylidene)-4-hydroxybenzohydrazide and N’-(2-hydroxybenzylidene)-2-hydroxy-3-methylbenzohydrazide, respectively, have been synthesized. The complexes have been characterized by elemental analyzes, IR spectra, molar conductance data, and single crystal X-ray determination. Mo in each complex is octahedral. The crystals of the complexes are stabilized by hydrogen bonds and weak π π stacking interactions. The complexes function as effective olefin epoxidation catalysts with hydrogen peroxide as oxidant and sodium hydrogen carbonate as a co-catalyst at room temperature.

Keywords:

• Benzohydrazone
• Molybdenum
• Crystal structure
• Hydrogen bonding
• Olefin epoxidation

Acknowledgements

The author greatly acknowledges Jingchu University of Technology for financial support.