循环烯的酶选择性,面向选择性碳磁化
1Brown Laboratories, Department of Chemistry and Biochemistry, University of Delaware, Newark, Delaware 19716, USA.
Journal of the American Chemical Society
|April 28, 2006
概括
这项研究引入了一种新的方法,可以使用性联结体从简单的原始材料制造复杂的分子. 该过程实现了高面部选择性和enantioselectivity,有效地产生多个立体中心.
科学领域:
- 有机化学 有机化学
- 不对称的合成方法
- 立体选择性反应
背景情况:
- 开发有效的方法来创建复杂的分子架构与定义的立体化学是有机合成的一个重大挑战.
- 普罗基拉环烯为构建立体化学丰富的化合物提供了独特的反应性.
- 不对称的催化对于控制化学转换中的酶选择性至关重要.
研究的目的:
- 开发一种可选择性和可选择性添加碳核友的碳核友到前体的3-氧甲基cyclopropenes.
- 创建一个连续的加法/捕获序列,以合成最多四个立体中心的复杂和多样化的产品.
- 研究一种廉价且可回收的性联结体用于诱导不对称性.
主要方法:
- 采用了一种双重添加/捕获序列,涉及亲性3-基甲基cyclopropenes和碳核友.
- 采用 (S) -N-甲基醇作为激素配体来诱导不对称性.
- 研究了甲氧化物在实现高反选择性方面的作用.
主要成果:
- 在添加反应中实现了高面部选择性和反选择性 (90-98% ee与MeMgCl).
- 从三个简单的材料中成功生成了多达四个立体中心的复杂产品.
- 与与aryldiazoacetates的enantioselective环化相比,已经证明了补充性的二选择性.
- 确定了 methoxide 对于高的 enantioselectivities 的必要性,并提供了证据,证明至少有两个奇拉连接体参与了立体化学决定步骤.
结论:
- 描述的方法提供了一条有效的途径,通过不对称的添加到cyclopropenes通过复杂的性分子.
- 廉价且可回收的 (S) -N-甲基醇联体使得这种转化过程中具有很高的反抗选择性.
- 这些发现为这种新型反应系统中不对称诱导的机制提供了宝贵的见解.
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