Chiral amplification based on enantioselective dual-phase distribution of a scalemic bisoxazolidine catalyst.
Chiral amplification based on enantioselective dual-phase distribution of a scalemic bisoxazolidine catalyst.
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基于尺度双恶唑烷催化剂的对映选择性双相分布的手性放大。
DOI：
10.1021/ol070915j
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发表时间：
2007
期刊：
影响因子：
5.2
通讯作者：
C. Wolf
中科院分区：
文献类型：
--
作者：
Shuanglong Liu;C. Wolf
发现一个容易获得的双恶唑烷配体催化醛与Et(2)锌和活性较低的Me(2)锌的不对称烷基化反应，在这两个反应中都提供了高的产率和ee‘s。双恶唑烷催化苯甲醛的烷基化和炔化反应表现出一种不能用Kagan的ML(N)模型解释的正的非线性效应。手性放大来源于选择性相分布，有利于规模化催化剂的主要对映体在溶液中的浓缩。
A readily available bisoxazolidine ligand was found to catalyze the asymmetric alkylation of aldehydes with Et(2)Zn and less reactive Me(2)Zn, providing high yields and ee's in both reactions. The bisoxazolidine-catalyzed alkylations and alkynylation of benzaldehyde show a positive nonlinear effect that cannot be accounted for by Kagan's ML(n) model. The chiral amplification originates from selective phase distribution favoring enrichment of the major enantiomer of the scalemic catalyst in solution.