Département de Chimie Moléculaire (SERCO) UMR 5250, ICMG FR-2607, CNRS-Université Joseph Fourier, BP 53, 38041 Grenoble Cedex 09, France.
Org Lett. 2012 Apr 20;14(8):2034-7. doi: 10.1021/ol300550x. Epub 2012 Apr 10.
Nitrones and tert-butanesulfinyl imines undergo conjugate addition to alkyl allenoates under SmI(2)-mediated reductive coupling conditions to produce novel β-methylenyl-substituted γ-amino esters. The latter were readily transformed into the corresponding β-methylenyl-γ-lactams by simple zinc reduction (N-hydroxy amines) or by acid hydrolysis (sulfinamides). The diastereoselective preparation of various β-methylenyl-γ-lactams offers a route to tetramic acids, the key structural features of an important class of bioactive natural products.
氮氧化物和叔丁基亚磺酰亚胺在 SmI(2)介导的还原偶联条件下与烷基丙二烯酸酯发生共轭加成反应，生成新型β-亚甲基取代的γ-氨基酯。后者通过简单的锌还原（N-羟基胺）或酸水解（亚磺酰胺）很容易转化为相应的β-亚甲基-γ-内酰胺。各种β-亚甲基-γ-内酰胺的非对映选择性制备为四氢酸提供了途径，四氢酸是一类重要的生物活性天然产物的关键结构特征。
