Molybdenum containing surface complex for olefin epoxidation
نویسندگان
چکیده
Silica-supported molybdenum surface complexes were prepared by the reaction between (N=)Mo(OtBu)3 and silica via displacement of the tert-butoxy ligands for siloxyls from the silica surface. The structure of the surface molybdenum complexes was well defined by in-situ FT-IR, elemental analysis, H NMR and C CP/MAS NMR techniques. The surface complexes could undergo alcoholysis reaction with CD3OD and CH3OH in the same way as free (N=)Mo(OtBu)3 and they show high catalytic activity and selectivity in olefin epoxidation. Initial rates up to 24.9 mmol epoxide (mmol Mo) 1 min 1 were achieved in the epoxidation of cyclohexene using TBHP as oxidant.
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