Studies on quinones. 24. Rearrangement of Diels-Alder adducts of activated quinones under acidic conditions
作者:Francisco Fariña、M.Carmen Paredes、Jaime A. Valderrama
DOI:10.1016/s0040-4020(01)81237-0
日期:1992.1
The Diels-Alder adducts 4, 19, 9, 10, 8, 11, of benzoquinones bearing activating groups (COCH3 COCH=CHPh, CO2Me, NO2 CHO, CN) by treatment with 1,3 N hydrochloric acid are initially converted into the dihydrobenzofurans 7, 22, the corresponding alcohols 12, 13 or the arylcrotonaldehydes 14, 15, respectively. By treatment with 8.5 N hydrochloric acid, adducts 8–10 are converted directly into the corresponding
的狄尔斯-阿德耳加成物4,19,9,10,8,11,苯醌轴承活化基团(COCH的3 COCH = CHPh配合,CO 2 Me中,NO 2 CHO,CN)通过用1,3-当量盐酸最初转化成二氢苯并呋喃7,22,相应的醇12,13或arylcrotonaldehydes 14,15,分别。通过用8.5 N盐酸处理,加合物8-10直接转化为相应的二氢苯并呋喃。在硅胶的存在下,加合物19被部分转化为苯并环辛三烯衍生物21。通过加合物25的水解形成的醇26在硅胶和乙醇或甲醇的存在下分别重排至苯并二呋喃衍生物28和29。