Enantio- and Di Aereodivergent Dual Catalysis: α-Allylation of Branched Aldehydes
Enantio- and Di Aereodivergent Dual Catalysis: α-Allylation of Branched Aldehydes
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DOI：
10.1126/science.1237068
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发表时间：
2013-05-31
期刊：
影响因子：
56.9
通讯作者：
Carreira, Erick M.
中科院分区：
文献类型：
--
作者：
Krautwald, Simon;Sarlah, David;Carreira, Erick M.
不对称合成中的一个重要挑战是开发完全立体发散的策略，以获得含有多个立体中心的产品的全部立体异构体。在理想的情况下，有四个产品是可能的，在相同的条件下将不同的催化剂应用到同一组起始材料上，可以一步得到任何给定的立体异构体。在这里，我们描述了这一概念在全立体发散双催化合成伽马，三角洲不饱和醛附近的四元/三元立体生成中心的实现。该反应是由手性铱催化剂和胺催化剂实现的，它们分别激活了烯丙醇和醛底物。每一种催化剂都施加了高度的局部立体控制，而不考虑对方的固有偏好。
An important challenge in asymmetric synthesis is the development of fully stereodivergent strategies to access the full complement of stereoisomers of products bearing multiple stereocenters. In the ideal case, where four products are possible, applying distinct catalysts to the same set of starting materials under identical conditions would in a single step afford any given stereoisomer. Herein, we describe the realization of this concept in a fully stereodivergent dual-catalytic synthesis of gamma,delta-unsaturated aldehydes bearing vicinal quaternary/tertiary stereogenic centers. The reaction is enabled by chiral iridium and amine catalysts, which activate the allylic alcohol and aldehyde substrates, respectively. Each catalyst exerts high local stereocontrol irrespective of the other's inherent preference.