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以N-双[γ-(三乙氧基硅基)丙基]胺对MCM-41修饰,得到仲氨基修饰的MCM-41,进而通过接枝法将手性Salen-Mn(Ⅲ)配合物固载在介孔分子筛MCM-41上,得到两个不同Mn含量的多相化催化剂.采用XRD,N2吸附,电感耦合等离子体发射光谱(ICP),傅里叶变换红外光谱(FT-IR),紫外-可见光谱(UV-Vis)等手段对固相化催化剂进行了表征.分别以次氯酸钠、间氯过氧苯甲酸为氧化剂,考察了催化剂对烯烃不对称环氧化反应的催化性能和循环使用性能.发现催化剂在固相化后,其活性和对映体选择性都大大降低.并讨论了导致催化剂活性和对映体选择性降低的原因.
MCM-41 was modified with N-bis [γ- (triethoxysilyl) propyl] amine to obtain secondary amino-modified MCM-41. The chiral Salen-Mn Were immobilized on the mesoporous molecular sieve MCM-41, and two heterogeneous catalysts with different Mn contents were obtained.XRD, N2 adsorption, ICP-ICP, FT-IR, , UV-Vis (UV-Vis) were used to characterize the immobilized catalyst.The effects of catalyst on the asymmetric epoxidation of olefins were investigated by using sodium hypochlorite and m-chloroperoxybenzoic acid as oxidants respectively. Performance The catalysts were found to have greatly reduced activity and enantioselectivity after immobilization and the reasons leading to a decrease in catalyst activity and enantioselectivity were discussed.