Synthesis of 4,4-Disubstituted β-Lactams by Regiospecific Electrophile- and Silver-Induced Ring Expansion of 2,2-Disubstituted 1-Methoxycyclopropylamines
作者:Norbert De Kimpe、Kourosch Abbaspour Tehrani、Gwendolien Fonck
DOI:10.1021/jo960296k
日期:1996.1.1
2,2-Disubstituted 1-methoxycyclopropylamines underwent regiospecific ring expansion to 1,4,4-trisubstituted 2-azetidinones by N-chlorination with tert-butyl hypochlorite and subsequent rearrangement with silver tetrafluoroborate. Upon thermolysis, 4,4-disubstituted beta-lactams suffer a characteristic ring opening to afford beta,gamma-unsaturated carboxylic amides. The reduction of 1,4,4-trisubstituted
通过用次氯酸叔丁酯进行N-氯化和随后用四氟硼酸银重排,使2,2-二取代的1-甲氧基环丙胺区域特异性环扩环成1,4,4-三取代的2-氮杂环丁酮。在热解时,4,4-二取代的β-内酰胺具有特征性的开环,以提供β,γ-不饱和的羧酸酰胺。用氢化铝锂还原1,4,4-三取代的2-氮杂环丁酮,得到1,2,2-三取代的氮杂环丁烷。