3-(噻吩-2-基)-β-内酰胺的合成及其立体化学

Staudinger 反应是合成β-内酰胺类化合物最重要的方法之一. 3-(噻吩-2-基)-β-内酰胺是一类重要的β-内酰胺类衍生物. 发展了一种从1-(噻吩-2-基)-4,4,4-三氟-1,3-丁二酮和对甲苯磺酰叠氮方便地制备1-(噻吩-2-基)-2-重氮基乙酮的新方法, 利用1-(噻吩-2-基)-2-重氮基乙酮加热分解生成的噻吩-2-基烯酮参与的Staudinger反应合成了一系列3-(噻 吩-2-基)-β-内酰胺衍生物, 并研究了噻吩-2-基烯酮参与的Staudinger反应的立体选择性. 实验结果表明噻吩-2-基烯酮是比苯基烯酮更富电子的Moore烯酮, 其电子性质介于对甲氧基苯基烯酮和对甲基苯基烯酮之间.

Synthesis and Stereochemistry of 3-(Thiophen-2-yl)-β-lactams

The Staudinger reaction is one of the most important methods in synthesis of β-lactams. 3-(Thiophen-2-yl)-β-lactam is one class of important β-lactam derivatives. A convenient and new method was developed to synthesize 2-diazo-1-(thiophen-2-yl)-ethanone from 4,4,4-trifluoro-1-(thiophen-2-yl)- 1,3-butanedione and tosyl azide. A series of 3-(thiophen-2-yl)-β-lactams were synthesized via the Staudinger reaction of imines and thiophen-2-ylketene generated thermally from 2-diazo-1-(thiophen-2-yl)-ethanone. The stereoselectivity of the Staudinger reaction was also investigated. The results indicate that thiophen-2-ylketene is a more electron-rich Moore ketene than phenylketene and its electronic property locates between those of 4-methoxyphenylketene and 4-methylphenylketene.