催化不对称化产生性二甲基甲与弱协调或非协调的替代剂
Päivi Tolstoy1, Mattias Engman, Alexander Paptchikhine
1Department of Biochemistry and Organic Chemistry, Uppsala University, Box 576, SE-751 23 Uppsala, Sweden.
Journal of the American Chemical Society
|June 26, 2009
概括
研究人员开发了一种新的催化不对称化方法,用于创建二甲基的性中心. 这种方法实现了对各种基质的高酶选择性,这对于制药合成至关重要.
科学领域:
- 有机化学 有机化学
- 不对称的催化剂.
- 药用化学 医学化学
背景情况:
- 在许多药品和天然产品中,二甲立体中心是重要的结构动图.
- 有效和选择性的合成方法来构建这些性中心具有重要的工业意义.
- 现有的方法在复杂结构的基质范围或酶选择性方面可能存在局限性.
研究的目的:
- 开发一种新型的催化系统,用于三替代烯酸的不对称化.
- 为了高效地合成具有高反体过量 (ee) 的二甲基甲基拉中心.
- 研究催化剂结构在实现高立体选择性的作用.
主要方法:
- 使用与新型N,P-化配体协调的复合物的应用.
- 不对称的化广泛的三替代烯.
- 使用奇拉色谱分析反应产物的分析,以确定enantioselectivity.
主要成果:
- 对于目标二甲基甲性中心,实现了高转换率和优异的酶选择性 (高达99% ee).
- 证明了广泛的基质范围,包括具有极小差异的亲基质碳 (例如,和p-tolyl组) 的具有挑战性的基质.
- 提供了证据,支持催化剂活性部位内的固体阻碍在决定立体选择中的作用.
结论:
- 开发的催化不对称化是一种高效的合成二甲基立体中心的方法.
- 催化剂系统表现出了显著的立体分辨能力,即使是对固态相似的替代剂.
- 这种方法为工业合成与药品和天然产品相关的奇拉化合物提供了有价值的工具.
相关概念视频
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