具有高度反选择性的 imine 糖化,具有显著的二元立体化学开关
John D Huber1, James L Leighton
1Department of Chemistry, Columbia University, New York, New York 10027, USA.
Journal of the American Chemical Society
|November 7, 2007
概括
一种新方法使得使用一种奇拉性 cinnamylsilane 的方法能够对 aldimines 进行 enantioselective cinnamylation. 这种方法实现了高选择性,通过修改 imine,简化合成路径,允许通过改变 imine 来控制 diastereochemical.
科学领域:
- 有机化学 有机化学
- 不对称的合成方法
背景情况:
- 阿尔迪明是多功能合成中间体.
- 对药品和精细化学品而言,酶选择性合成至关重要.
- 现有的肉化方法往往缺乏效率或广泛适用性.
研究的目的:
- 开发第一个针对阿尔迪明酶的酶选择性amylation的一般方法.
- 在这种转化过程中,要达到高的酶选择性和二聚体化学控制.
- 通过避免需要分离试剂的 cis 和 trans 异构体来简化合成策略.
主要方法:
- 使用了一种简单的合性胺烯基试剂.
- 研究了奇拉 cinnamylsilane 与各种 aldimines 的反应.
- 探索了对 imine 结构的微妙变化,以控制 diastereoselectivity.
主要成果:
- 实现了第一个对阿尔迪米因酶的酶选择性amylation的一般方法.
- 显示出异常高水平的反选择性.
- 观察到一个前所未有的二聚体化学逆转,允许从相同的跨-cinnamylsilane访问任何二聚体.
结论:
- 开发的方法提供了一种简单且高度抗选择性的途径,以获得amylated aldimines.
- 通过 imine 修饰来控制 diastereochemistry 的能力代表了一个重要的进步.
- 这项工作简化了合成对有价值的性化合物的获取.
相关概念视频
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