功能化性基因的灾难选择性锡拉cyclopropanations的功能化基因
Tom G Driver1, Annaliese K Franz, K A Woerpel
1Department of Chemistry, University of California, Irvine, California 92697-2025, USA.
Journal of the American Chemical Society
|June 6, 2002
概括
的降解和热烯转移使得性烯的高度二分体选择性烯烯基烯酸化. 绝缘因素,而不是氧气效应,决定了反应的发生.
科学领域:
- 有机化学 有机化学
- 立体选择性合成 立体选择性合成
- 有机合成 有机合成
背景情况:
- 锡拉cyclopropanes是有价值的合成中间体.
- 开发用于它们的合成的 diastereoselective 方法至关重要.
研究的目的:
- 探索降解和热烯转移用于二聚选择性cyclopropanation.
- 为了研究这些反应中的立体化学控制.
主要方法:
- 降解二三丁二西兰.
- 在105-125°C的温度下进行热烯转移反应.
- 功能化性烯的环化,包括环素,环烯,诺波烯和1,1-异位烯.
主要成果:
- 实现了高度二分体选择性的环化 (92:8到>99:1).
- 证明了固态相互作用控制了立体化学结果,取代了潜在的氧气导向效应.
- 鉴定了由于温度升高而对某些基板的热烯转移的限制.
结论:
- 还原和热转移是对二聚选择性cyclopropanation的补充和有效的.
- 烯中间体的绝缘质量是二聚体选择性的主要决定因素.
- 功能化的锡拉cyclopropanes可以被精制成复杂的多氧化产品.
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