3-(2'-羧乙基)苯并噻吩的合成与表征

3—(2′—羧乙基)苯并噻吩作为一种极为重要的化工原料,其传统的合成方法,产率仅达60%左右,实验条件难以掌握。为提高该物质的收率,降低原料消耗,寻求较为理想的合成方法,文中介绍了以苯并噻吩、丙二酸二乙酯、氢化钠为主要原料,合成3—(2′—羧乙基)苯并噻吩的方法。经大量合成实验条件探索,苯并噻吩的氯甲基化在室温下进行,用氢化钠代替醇钠,用二甲基甲酰胺(DMF)为溶剂,在加热条件下进行均相脱羧反应,抑制了副反应的发生,从而提高了产品收率。并经熔点测定,¹H-NMR、¹³C-NMR、质谱及元素分析,表征其合成得到的3—(2′—羧乙基)苯并噻吩的结构。

SYNTHESIS AND CHARACTERIZATION OF3 -(2'-CARBOXYETHYL )BENZO[B]-THIOPHENE

A new synthetic method of 3-(2’-carboxyethyl)benzo [b]thiophene is developed, which can reduce side effects and achieved higher yields. The synthetic reaction of 3-chloromethyl benzo[b]thiopene took place under room tempera-ture. Homogeneous decarboxylation was carriedout under heat-ing by using sodium methoxide instead of sodium hydride andN,N-dimethylformamide (DMF) as a solvent. Meanwhile,the structure of 3-(2’-carboxyethyl)benzo[b]thiophene was confirmed by testing melt point, NMR, Mass Spectrometry and elementary analysis .