一种高度调节的立体选择性olefination半稳定三基化物与N-sulfonyl imines
De-Jun Dong1, Hai-Hua Li, Shi-Kai Tian
1Department of Chemistry, University of Science and Technology of China, Hefei, Anhui 230026, China.
Journal of the American Chemical Society
|March 23, 2010
概括
这项研究引入了一种新的维蒂格反应协议,使用N-硫尼尔胺而不是化物. 这种方法显著提高了基合成中的立体选择性,为Z-和E-基异构体实现了99:1以上的选择性.
科学领域:
- 有机化学 有机化学
- 合成化学 合成化学
背景情况:
- 维蒂格反应是烯合成的基石.
- 传统的维蒂格反应通常会产生Z-和E-基异构体的混合物,特别是半稳定型化物.
- 在基合成中实现高立体选择性仍然是一个重大挑战.
研究的目的:
- 开发一种更具立体选择性的烯合成协议.
- 在控制烯几何学方面克服传统维蒂格反应的局限性.
- 将开发的方法应用于合成有价值的有机化合物.
主要方法:
- 在维蒂格反应中用N-硫尼尔胺替代化物.
- 用各种芳香,α,β不和和酸N-硫胺基的基化.
- 采用温和的反应条件来进行炼过程.
主要成果:
- 为高度刻板选择性烯合成建立了一个简单而高效的协议.
- 这种反应使结合基 (Z-和E-异构体) 产生良好的至优良的产量.
- 合成的基异构体的立体选择性超过99:1得到了实现.
- 该协议已成功应用于对抗癌药物DMU-212及其Z-同位素的立体选择性合成.
结论:
- 使用N-硫尼尔胺为维蒂格反应的立体选择性提供了显著的改善.
- 这种可调节的协议提供了一条通往立体定义基因的多功能路线.
- 该方法对高效合成复杂分子,包括药品具有前景.
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