Catalytic Epoxidation of Stilbene

Since the epoxidation of alkenes with peracids was discovered by Prilezajew in 1909 [29], epoxides have played a major role in organic chemistry and industry, providing important intermediates for the synthesis of more complex molecules. Metal-catalyzed epoxidation reactions have received much attention in recent decades since the discovery of the Sharpless epoxidation [30, 31], but most epoxides were prepared from alkenes primarily by their interaction with peracids. 

An IBA/O2 system is one of the most efficient oxidants for synthesis systems using O2 [32] and has become a powerful tool for the selective epoxidation of various organic compounds [33, 34], 

The three-coordinated unsaturated structure of the Ru complex remained unchanged after 1000 cycles of the stilbene epoxidation as suggested by XPS, DR-UV/Vis and XAFS. The unsaturated Ru complex 5 is active for the epoxidation reaction. Notably, the three-coordinate Ru complex 5 is quite stable under the reaction conditions and also in air despite its unsaturated structure. This remarkable stability and durability made the immobilized catalyst 5 recyclable for the catalytic reactions, maintaining 100% conversion with selectivity higher than 80% [17]. 

Chiral Self-Dimerization of V Complexes on a SiOj Surface for Asymmetric Catalysis 

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