Diferrocenyldiimine Dioxomolybdenum Complexes: Structures(Electrochemistry), Catalytic Activity And Catalytic Mechanism

The epoxidation of olefins is one of the important methods for the synthesis of the epoxides, and the research of the catalyst for the olefin epoxidation is a hotspot in chemistry at the present time. Transition metal complexes such as molybdenum complex is an efficient catalyst for olefin epoxidation which aroused the interest of chemical workers.In this paper, three ferrocenylimine dioxomolybdenum(VI) complexes MoO2Cl2L1～3 were synthesized(Fig.1) and characterized by elemental analysis, ICP, XRD, TGA and cyclic voltammetry.The coordination numbers and stability constants were also determined using Mole method.The complexes were evaluated as catalysts for cyclohexene epoxidation by tert-butylhydroperoxide in 1,2-dichloroethane. The experimental results indicated that all of the dioxomolybdenum(VI) complexes MoO2Cl2L1～3 showed high catalytic activity, and the catalytic activity of complexe MoO2Cl2L2 was the highest one. The reaction mechanism of complexes MoO2Cl2L and TBHP was studied by infrared spectroscopy, meantime the reaction kinetics were studied using UV-Vis spectrometer method.This was the first report that solvent-free reaction of ferrocenylimine ligands L with MoO2Cl2 were studied in dark conditions.