在金属酸盐催化下,对α,β不和胺基进行非对称的化
Mary R Nahm1, Justin R Potnick, Peter S White
1Department of Chemistry, University of North Carolina at Chapel Hill, 27599-3290, USA.
Journal of the American Chemical Society
|February 24, 2006
概括
一种新型的TADDOL酸盐催化剂使得对不和氨基酸具有高度反选择性的合添加基烯酸. 由此产生的产品可以很容易地被丰富到高反体过剩,从而产生可用于进一步合成的有价值的中间体.
科学领域:
- 有机化学 有机化学
- 催化剂是一种催化剂.
- 不对称的合成方法
背景情况:
- 结合添加反应是有机合成的基础.
- 选择性催化对于产生性分子至关重要.
- 乙基烯是碳-碳键形成的多功能试剂.
研究的目的:
- 开发一种高度选择性催化系统,用于合添加乙烯基.
- 探索开发的催化系统的范围和实用性.
- 阐明反应机制的关键方面.
主要方法:
- 使用一种l-menthone衍生的TADDOL酸盐 (6b) 作为一种性催化剂.
- 对N,N-二甲基烯胺衍生物添加p-methoxybenzoylcyclohexyldimethylsilane的酶选择性联合添加.
- 通过再结晶来丰富产品.
- 脱和Baeyer-Villiger氧化用于进一步的转化.
- 机械学研究的X射线衍射和交叉实验.
主要成果:
- 在TADDOL酸6b催化高度enantioselective结合物添加 (高达99% ee).
- 产品在再结晶时经历了容易的反缩.
- 脱提供了正式的斯特特添加产品,随后的氧化产生了产品.
- X射线衍射揭示了对催化物的结构影响.
- 交叉实验证实了迁移的分子内性质.
结论:
- 开发的TADDOL酸盐催化剂对乙烯基烯酸盐的enantioselective结合物添加有效.
- 反应通过随后的转化提供了获取有价值的性中间体的途径.
- 该研究提供了对催化循环的机械洞察,包括分子内迁移.
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