Ring transformations of 2,3-dihydroisoxazoles via azomethine ylides—formation of annulated 5- and 7-membered N-heterocycles
作者:Wolfgang Friebolin、Wolfgang Eberbach
DOI:10.1016/s0040-4020(01)00322-2
日期:2001.5
On thermal activation the 2,3-dihydroisoxazoles 12–14 are transformed into annulated dihydroazepines 15–17 as main products, besides minor amounts of the corresponding pyrrole derivatives 18–20. In the proposed mechanism the azomethine ylides of type III and VI are involved as intermediates which undergo 1,5- and 1,7-ring closure reactions, respectively.
在热活化的2,3- dihydroisoxazoles 12 - 14被变换成稠dihydroazepines 15 - 17作为主要产品,除了相应的吡咯衍生物的少量18 - 20。在所提出的机理中,III和VI型的甲亚胺基团作为中间体,分别经历1,5-和1,7-环闭合反应。