【摘要】 以L-氨基酸为手性源,合成了一系列新型手性咪唑鎓环番,并进行了结构表征.在碱性条件下,L-氨基酸和乙二醛、甲醛缩合生成了(S)-2-(1-咪唑)羧酸钠,转化为甲酯后与乙二胺进行胺解反应制得开链手性咪唑二酰胺,然后与二溴化合物在高稀淡技术和无水条件下进行季铵化关环反应,再进行阴离子交换制得目标分子(4~6).以手性咪唑鎓环番为主体分子,研究了对氨基酸及其衍生物的对映选择性识别作用.更多还原

【Abstract】 A series of novel chiral imidazolium cyclophanes were synthesized from natural amino acids. (S)-2- (1-Imidazolyl)alkanoates(2) were prepared by cyclization and esterification. In the presence of DMAP and Et_ 3 N. Alkanoates(2) reacted with ethylenediamine to yield compounds 3 with satisfactory yields. Compounds 3 reacted with 2,6-bis(bromomethyl)- 4-chlorphenol, 1,3-bis(bromomethyl)benzene or 2,6-bis(bromomethyl)pyridine to afford dibromide salts under high dilution and anhydrous condition. Finally, the hexafluorophosphates (4—6) were obtained by treating the corresponding dibromide salts with a saturated aqueous solution of NH_ 4 PF_ 6 . The structures of the target compounds were confirmed by IR, ~ 1 H NMR, MS, HRMS, and elemental analysis. These compounds featured large cavities and multipoint binding sites. UV spectroscopic titration experiments showed these chiral imidazolium cyclophanes exhibited good enantioselective recognition toward L- and D-amino acids and their derivatives.更多还原