由可溶性恒星聚合物催化的单多组件不对称级联反应,具有高度分支的非相互透的催化核
Yonggui Chi1, Steven T Scroggins, Jean M J Fréchet
1Division of Materials Sciences, Lawrence Berkeley National Laboratory, and College of Chemistry, University of California, Berkeley, California 94720-1460, USA.
Journal of the American Chemical Society
|April 25, 2008
概括
星聚合物催化剂模仿酶,使一个的不对称级联反应与多个催化剂. 这一策略提供了对所有立体异构体的访问,展示了用于复杂性分子合成的先进聚合物催化剂.
科学领域:
- 聚合物化学 聚合物化学
- 催化剂是一种催化剂.
- 有机合成 有机合成
- 超分子化学 超分子化学
背景情况:
- 酶通过精确的活性位点的空间布局来实现显著的催化效率和选择性.
- 在合成催化剂中模仿酶活性部位隔离对于使多催化剂系统成为可能至关重要.
- 不对称级联反应为复杂分子提供了有效的途径,但通常由于催化剂不兼容而受到阻碍.
研究的目的:
- 设计和合成非相互透的星聚合物催化剂,模仿酶的隔离位点.
- 为了实现不对称级联反应的多个,否则不兼容的催化剂的单组合.
- 为了实现复杂的性分子与多个立体中心的受控合成.
主要方法:
- 合成非相互透的星聚合物,其功能与催化剂部分.
- 不对称级联反应涉及,酶胺和H结合催化.
- 使用小分子和线性聚合物类似物进行控制实验.
- 对级产品的立体同位素分布的分析.
主要成果:
- 星级聚合物催化剂成功促进了涉及多种催化功能的单不对称级联反应.
- 控制实验证明了星聚合物架构对于级联反应效率的必要性.
- 该策略允许通过控制催化剂性来选择性合成级联产品的单个立体同位素.
结论:
- 非相互透的星聚合物有效地为可溶性聚合物催化剂提供类似酶的位点隔离.
- 这种方法可以开发复杂的不对称级联反应,具有前所未有的控制.
- 这项研究代表了可溶性聚合物的应用在酶模拟催化和复杂合合成方面的重大进展.
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