Enantioselective Staudinger synthesis of β-lactams catalyzed by a planar-chiral nucleophile
Enantioselective Staudinger synthesis of β-lactams catalyzed by a planar-chiral nucleophile
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DOI：
10.1021/ja012427r
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发表时间：
2002-02-27
影响因子：
15
通讯作者：
Fu, GC
中科院分区：
文献类型：
--
作者：
Hodous, BL;Fu, GC
由于β-内酰胺的生物活性和作为合成中间体的用途，开发立体选择性生成β-内酰胺的有效方法是一个重要的目标。施陶丁格反应是乙烯酮与亚胺的整体 [2 + 2] 环加成反应，为该类化合物提供了一条很好的收敛途径。迄今为止，几乎所有关于施陶丁格反应不对称变体的研究都集中在使用手性助剂来控制 β-内酰胺的立体化学。在本报告中，我们确定 4-(吡咯烷)吡啶的平面手性衍生物可作为 Staudinger β-内酰胺合成的非常有效的对映选择性催化剂，将一系列对称和不对称乙烯酮与一系列亚胺偶联，具有非常好的立体选择和产率。
The development of efficient methods for the stereoselective generation of β-lactams is an important goal, due to their biological activity and their utility as synthetic intermediates. The Staudinger reaction, an overall [2 + 2] cycloaddition of a ketene with an imine, provides a nicely convergent route to this family of compounds. Nearly all studies to date of asymmetric variants of the Staudinger reaction have focused on the use of chiral auxiliaries to control the stereochemistry of the β-lactam. In this report, we establish that a planar-chiral derivative of 4-(pyrrolidino)pyridine serves as a very effective enantioselective catalyst for the Staudinger β-lactam synthesis, coupling a range of symmetrical and unsymmetrical ketenes with an array of imines with very good stereoselection and yield.