关键词: 低聚苯乙烯基膦酸-磷酸氢锆, 手性Salen Mn(Ⅲ) 催化剂, 固载, 不对称环氧化

Abstract: Chiral salen complexes are among the most important catalyts for asymmetric synthesis. But the soluble salen manganese complex are more difficult to be separated and to handle than the technically well established heterogeneous catalysts. An important strategy to combine the best property of the two types is the heterogenization or immobilization of active salen complex on supports or carriers, which may be seperated by filtration or precipitation. In this paper, a new way of the covalent immobilization of Salen Mn(Ⅲ) complex on a organic-innoganic mataterial to produce a stable heterogeneous catalyst for epoxidation are reported. Chiral Mn(Salen) complex was axially immobilized onto sulfomethylated zirconium oligostyrenyl phosphonate-phosphate(ZSMSPP), then characterized by FTIR, diffusion reflection UV-Vis, AAS, SEM, TEM, TG and N₂ volumetric adsorption. The effects of reaction parameters such as oxidant, temperature, time and catalyst amount in the epoxidation of styrene are discussed, the result shows that this heterogeneous catalyst exihibits effective catalytic activity, and this heterogeneous Salen Mn(Ⅲ) catalyst is relatively stable and can be recyled for six times in the asymmetric epoxidation of styrene.

Key words: Zirconium oligo-polystyrenylphosphonate-phosphate(ZSPP), Chiral Salen Mn(Ⅲ) catalyst, Immobilization, Asymmetric epoxidation