对于中桥扭曲乳的核友添加反应中的近距离效应:非常稳定的四面体中间体
Michal Szostak1, Lei Yao, Jeffrey Aubé
1Department of Medicinal Chemistry, University of Kansas, 1251 Wescoe Hall Drive, Malott Hall, Room 4070, Lawrence, Kansas 66045-7852, USA.
Journal of the American Chemical Society
|January 26, 2010
概括
研究人员探索了压缩乳酸与有机金属试剂的反应,发现了稳定的 hemiaminals. 这项研究详细介绍了影响乳母体体内血氨基稳定性和独特反应模式的因素.
科学领域:
- 有机化学 有机化学
- 立体化学是一种立体化学.
- 反应机制 反应机制
背景情况:
- 乳酸盐是循环胺,在有机合成中具有多样化的应用.
- 紧张的环系统往往表现出独特的反应性,由于扭曲的结合角度.
- 有机金属试剂是碳-碳键形成的多功能工具.
研究的目的:
- 用有机金属试剂研究压缩双循环和三循环单碳桥接乳酸的反应性.
- 为了表征由这些应变的乳酸形成的 Hemiaminals 的稳定性和特性.
- 阐明分子几何学对胺键反应性的影响.
主要方法:
- 合成压缩的双循环和三循环乳前体.
- 使用各种有机金属试剂进行核性添加反应.
- 反应产物的光谱表征 (NMR,IR,质谱学).
- 对影响 Hemiaminal 稳定性的因素的分析.
主要成果:
- 从核性添加到扭曲的胺基键中分离出非常稳定的半氨基.
- 确定控制这些桥接式半矿物质稳定性的因素.
- 在某些情况下,观察了对氨基基的 hemiaminal 崩.
- 检测跨环N...C=O相互作用在九个成员的氨基基中.
- 三环乳与某些核爱素表现出类似类的反应性.
结论:
- 紧张的乳酸体几何学显著影响胺键反应性,使稳定的 hemiaminals 的形成.
- 这项研究定义了乳糖中胺与类碳烯活性之间的几何边界.
- 了解这些反应模式,可以了解复杂的含异环的合成.
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