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 CHC13. 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.%制备了多壁碳纳米管(MWCNTs)固载的金鸡纳生物碱季铵盐类手性相转移催化剂PTC-1/MWCNTs,并用于催化N-二苯亚甲基-甘氨酸叔丁酯的不对称烷基化反应中.采用紫外-可见光谱系统研究了五种有机溶剂对PTC-1在MWCNTs上吸附和脱附的影响.结果表明,在甲苯中,MWCNTs对PTC-1的吸附率最高(53％),而在三氯甲烷中PTC-1的脱附率最低(仅为0.75％).PTC-1/MWCNTs催化剂在催化N-二苯亚甲基-甘氨酸叔丁酯和不同卤代烃的不对称烷基化反应中,所得产物的收率和对映体选择性都较高,而且该催化剂可回收循环使用,说明PTC-1经MWCNTs固载后,仍能够有效地催化多种卤代烃的不对称烷基化反应.
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