Asymmetric [3,3]- and [1,3]-Sigmatropic Rearrangements of γ-Allyloxy Vinylogous Urethanes
作者:Yu-Jang Li、Yuan-Kang Chang、Guo-Ming Ho、Hua-Ming Huang
DOI:10.1021/ol901679h
日期:2009.9.17
a thermal [3,3]-sigmatropic rearrangement, providing compounds with N-substituted quaternary carbon centers. Cyclizations (subsequently or in situ) of the rearranged products generated hexahydro-3,4-dioxa-8a-aza-as-indacen-2-ones. Various terminally substituted allyloxy ketoesters and arylmethoxy ketoesters were found to generate tricyclic compounds via [1,3]-sigmatropic rearrangement. Finally, tricyclic
发现由脯氨醇或脯氨醇叔丁基二甲基甲硅烷基醚与4-烯丙氧基酮酯的缩合衍生的乙烯基氨基甲酸酯经历热的[3,3]-σ重排,提供具有N-取代的季碳中心的化合物。重排产物的环化(随后或原位)生成六氢-3,4-二氧杂-8a-氮杂-as-indacen-2-ones。发现各种末端取代的烯丙氧基酮酸酯和芳基甲氧基酮酸酯通过[1,3]-σ重排产生三环化合物。最后,将三环内酯成功转化为内酰胺。