带有奇拉性环烯胺的选择性布伦斯特德基催化
Jeffrey S Bandar1, Tristan H Lambert
1Department of Chemistry, Columbia University, New York, New York 10027, United States.
Journal of the American Chemical Society
|March 16, 2012
概括
基拉尔环烯胺是迈克尔反应中有效的反选择性布伦斯特德基催化剂. 这项研究展示了它们的准备性规模合成和应用,为不对称催化提供了一个新的工具.
科学领域:
- 有机化学 有机化学
- 不对称的催化剂.
背景情况:
- 基 Brønsted 基对于 enantioselective 合成至关重要.
- 环烯胺代表了一种新的有机基类.
研究的目的:
- 引入奇拉性环烯胺作为高效的反选择性布伦斯特基催化剂.
- 为了证明这些催化剂在不对称迈克尔反应中的实用性.
- 为催化剂提供可扩展的合成,并研究其特性.
主要方法:
- 使用一种性2,3-bis ((dialkylamino) cyclopropenimine催化剂的酶选择性迈克尔反应.
- 催化剂和产品的制备性规模合成.
- 循环烯胺的基本性测量.
- 质子化催化剂的X射线晶体学.
主要成果:
- 在一个甘氨酸胺基基质的迈克尔反应中实现了高的反抗选择性.
- 一个25克尺度的准备反应的演示.
- 报告了最佳催化剂的可扩展合成.
- 发现2,3-bis ((dialkylamino) cyclopropenimine的基本性与酸基相比较.
- 提供了X射线晶体结构和机械逻辑.
结论:
- 性环烯胺是一种强大的新型选择性布伦斯特德基催化剂.
- 这些催化剂有助于快速和高度选的迈克尔反应.
- 这些发现支持了催化反应的拟议机制和立体化学结果.
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