Unusual Diastereoselection in the Synthesis of Nine-Membered Ring Lactams and Conformation-Controlled Transannular Reactions to Generate Optically Active Indolizidinones
作者:Alexander Sudau、Udo Nubbemeyer
DOI:10.1002/(sici)1521-3773(19980504)37:8<1140::aid-anie1140>3.0.co;2-w
日期:1998.5.4
yielded almost exclusively the trans-3,8-disubstituted nine-membered ring lactams 2 (TBS=tBuMe2 Si), independent of whether cis or trans isomers were used as starting materials. The conformation (which provided facial chirality) of the medium-sized ring controlled the regio- and diastereoselectivities of the transannular reactions that afforded indolizidinones 3.
乙烯基吡咯烷1的aza-Claisen重排几乎完全产生了反式3,8-二取代的九元环内酰胺2(TBS = tBuMe 2 Si),而与使用顺式还是反式异构体无关。中型环的构象(提供面部手性)控制了提供吲哚并二酮3的跨环反应的区域选择性和非对映选择性。