Diastereoselective Route to Novel Fused or Bridged Tricyclic β-Lactams through Intramolecular Nitrone-Alkene Cycloaddition of 2-Azetidinone-Tethered Alkenylaldehydes - Synthetic Applications to Carbacephams and Cyclic β-Amino Acid Derivatives
作者:Benito Alcaide、Elena Sáez
DOI:10.1002/ejoc.200400792
日期:2005.4
tricyclic systems prepared, in order to demonstrate their potential as intermediates in the preparation of differently polyfunctionalized compounds, including carbacepham derivatives and related unconventional bicyclic systems containing medium-sized rings fused to the β-lactam nucleus, as well as several types of cyclic β-amino acid derivatives. (© Wiley-VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany
通过使用容易获得的单环 2-氮杂环丁酮链烯醛的分子内硝酮-烯烃环加成 (INAC) 反应作为关键合成步骤,开发了一种方便的、区域和立体选择性的直接制备光学纯异常稠合或桥连三环 β-内酰胺的途径. 环加成的区域选择性可以通过将烯烃取代基从 N1 移动到 2-氮杂环丁酮环上的 C3 来调节。此外,在制备的不同类型三环系统的代表性实例上测试了一些简单、有趣的转化,以证明它们作为制备不同多官能化合物的中间体的潜力,包括碳酰苯甲胺衍生物和相关的含有中等大小的非常规双环系统。与β-内酰胺核融合的环,以及几种类型的环状β-氨基酸衍生物。(© Wiley-VCH Verlag GmbH & Co. KGaA, 69451 Weinheim, Germany, 2005)