对纳扎罗夫反应的新方法是通过连续的电循环环开放和环闭合
1Department of Chemistry, University of Alberta, Edmonton, Alta., Canada T6G 2G2.
Journal of the American Chemical Society
|July 20, 2006
概括
这项研究引入了一种新的两步方法,用于从2-silyloxydienes中合成chlorocyclopentenones. 区域选择性二cyclopropanation和随后的白银催化纳扎罗夫循环提供了一个温和的替代方案,以创建化环.
科学领域:
- 有机化学 有机化学
- 合成化学 合成化学
背景情况:
- 纳扎罗夫循环化是合成环烯的关键反应.
- 纳扎罗夫循环化的现有方法可能是苛刻的或缺乏区域选择性.
研究的目的:
- 开发一种温和和区域选择性方法来合成cyclopentenones.
- 建立一个新的两步序列,涉及二cyclopropanation和Nazarov循环.
主要方法:
- 区域选择性二cyclopropanation的2-silyloxydienes. 这是一个非常好的方法.
- 银(I) 催化电循环开放和纳扎罗夫循环.
主要成果:
- 乙烯基cyclopropanol乙烯基乙烯被合成在良好的产量.
- 一个两步序列成功产生了环.
- 反应作为一个正式的4+1结构,引入素功能.
结论:
- 这种新的序列提供了一个方便和温和的替代标准纳扎罗夫循环协议.
- 该方法有效地产生有价值的化环丁衍生物.
- 在一个特定的情况下观察到一个中断的纳扎罗夫反应与一个基.
相关概念视频
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Selection Rules: Thermal Activation
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