| In recent years,the heterogeneous asymmetric catalysis has received more and more attention.Among all the reactions,the heterogeneous asymmetric epoxidation is the most impressive.In this paper,Zirconium poly(styrene-isopropenyl phosphonate)-phosphate (ZPS-IPPA),was synthesized.There are many caves,channels and pores with different shapes and sizes in the ZPS-IPPA particles.This kind of organic-inorganic hybrid materials has high thermal stability,acid and base stabilities, which can be used as a new kind of support material posessing advantages of organic-inorganic supports.In this work,it is pursued our research in the untapped area and diamine or ployamines modified ZPS-IPPA was prepared by the reaction of ZCMPS-IPPA with diamines or ployamines and then homogeneous chiral Salen Mn(Ⅲ) was immobilized onto the diamine or ployamines modified ZPS-IPPA by axial coordination thus a new type of heterogeneous chiral Salen Mn(Ⅲ) catalysts was obtained.All the heterogeneous chiral Salen Mn(Ⅲ) catalysts prepared were characterized by FT-IR, diffusion reflection UV-Vis,AAS,N2 volumetric adsorption,SEM,TEM and TG..The NaClO and m-CPBA were used as oxidant for asymmetric epoxidation of styrene,α-methylstyrene and indene respectively.The factors,such as amount of catalyst, co-catalyst,the reaction time,the reaction temperature solvent and axial length were investigated for asymmetric epoxidation ofα-methylstyrene.The results confirmed that the catalysts exhibit comparable or even higher activity and enantioselectivity for asymmetric epoxidation of various unfunctionalized alkenes than those of homogeneous Jacobsen's catalyst. Especially,in the epoxidation of a-methylstyrene,the conversion and enantiometric excess(ee) of 68%and 99%were obtained respectively.The catalysts were easily recovered by filtration and could be reused at least eight times with little loss of activity and enantioselectivity.
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