Synthesis, characterization and catalytic studies of bis(chloro)dioxomolybdenum(VI)-chiral diimine complexes

Six-coordinate dioxomolybdenum(VI) complexes of the type [MoO2Cl2L] containing bidentate chiral ligands were evaluated as catalysts for the asymmetric epoxidation of cis- and trans-β-methylstyrene by tert-butylhydroperoxide at either room temperature or 55 °C. The reactions proceeded with high retention of olefin configuration and high selectivity to the epoxide, but only for cis-β-methylstyrene were significant enantiomeric excesses obtained.