摘要：

The pyrene-tagged cinchona quaternary ammonium salt,the chiral phase transfer catalysts(PTC-1),was synthesized and immobilized on multi-walled carbon nanotubes(MWCNTs).The new catalysts(PTC-1/MWCNTs) were employed in enantioselective alkylation of N-(diphenylmethyene)glycine tert-butyl ester.UV-Vis absorption spectra show the effect of different organic solvents on the adsorption and desorption of PTC-1 onto and from MWCNTs,respectively.The results show that 5.3 mg PTC-1 can be loaded on 10 mg MWCNTs in toluene,and 0.02025 mg PTC-1 was desorbed from 12.7 mg PTC-1/MWCNTs when washed by CHCl3.In the enantioselective alkylation of different halohydrocarbons with N-(diphenylmethyene)glycine tert-butyl ester using PTC-1/MWCNTs as a catalyst,the alkylating products were obtained with high yield and ee value.Furthermore,PTC-1/MWCNTs catalyst can be recovered and used repeatedly.PTC-1/MWCNTs as a new catalyst is effective in enantioselective alkylation of multiple halohydrocarbon.

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