Synthesis of Chiral 2,5-Bis(oxazolinyl)thiophenes and Their Application as Chiral Shift Reagents for 1,1′-Bi-2-naphthol  

作　　者：高明章 汪波 刘汉标 许遵乐 

出　　处：《Chinese Journal of Chemistry》2002年第1期85-89,共5页中国化学（英文版）

基　　金：theNationalNaturalScienceFoundationofChina (No.2 9770 5 7)andGuangdongNaturalScienceFoundation

摘　　要：A series of C_2-symmetrical chiral 2,5-bis(4'-alkyloxazolin-2-yl) thiophenes(thiobox) have been synthesized from thiophene-2,5-dicarboxylic acid by sequential amidation with achiral ethanolamine, conversion of hydroxyl to chloro group, and base-promoted oxazoline ringformation. As demonstrated by (-)-2,5-bis[4'-(S)-isopropyloxazolin-2'-yl] thiophene, these thioboxsystems exhibited remarkable chirality recognition of 1,1'-bi-2-naphthol giving rise to pronouncedshifts in the ~1H NMR signals of the latter axial chiral compound at the positions of C-3, C-4, C-5,and C-8.A series of C_2-symmetrical chiral 2,5-bis(4'-alkyloxazolin-2-yl) thiophenes(thiobox) have been synthesized from thiophene-2,5-dicarboxylic acid by sequential amidation with achiral ethanolamine, conversion of hydroxyl to chloro group, and base-promoted oxazoline ringformation. As demonstrated by (-)-2,5-bis[4'-(S)-isopropyloxazolin-2'-yl] thiophene, these thioboxsystems exhibited remarkable chirality recognition of 1,1'-bi-2-naphthol giving rise to pronouncedshifts in the ~1H NMR signals of the latter axial chiral compound at the positions of C-3, C-4, C-5,and C-8.

关 键 词：C_2-symmetry 2 5-bis(oxazolinyl)thiophene chiral shift reagent 

分 类 号：O626[理学—有机化学]