Functionalized Cyclopropanes as Versatile Intermediates for the Diversity-Oriented Synthesis of γ-Lactones, γ-Lactams and δ-Lactams
作者:Marcus M. Sá、Adrielle P. Maximiano、Giovana S. Ramos、Marcelo V. Marques
DOI:10.1055/a-1389-1203
日期:2021.7
A two-step procedure for the preparation of cyclopropanecarboxaldehyde-1,1-diester from a γ,δ-epoxyester and its synthetic versatility are described herein. The epoxide ring-opening/cyclopropanation process occurs in the presence of Mg(ClO4)2 under heating, resulting in cyclopropanemethanol-1,1-diester in 65% yield. A mild TEMPO-mediated oxidation of this substrate readily generated the corresponding
本文描述了由γ,δ-环氧酯制备环丙烷甲醛-1,1-二酯的两步程序及其合成多功能性。环氧化物的开环/环丙烷化过程是在加热下存在Mg(ClO4)2的情况下发生的,从而以65%的收率得到环丙烷甲醇-1,1-二酯。轻度的TEMPO介导的该底物的氧化反应很容易以75%的产率生成相应的醛,该醛用于一锅法合成四个环亚丙基-γ-内酰胺和三个δ-内酰胺。另外,通过醛与phospho盐的维蒂希反应获得乙烯基环丙烷,并将其用作四氢呋喃的前体。