1,5-二芳基-6,7-二氧杂双环[3.2.2]壬烷1a – c(a:Ar = p -MeOC 6 H 4,b:Ar = p -MeC 6 H 4,c:Ar的光解和热解= Ph)进行了调查。(对-甲氧基苯基)-取代的1a进行新的光引发的O-新叶型1,2-芳基转移,得到1-(对-甲氧基苯基)氧基-5-(对甲氧基苯基)-8-氧杂双环[3.2。 1]辛烷7a和少量1-(p-甲氧基苯基)-3-(2-(4'-甲氧基苯基)四氢呋喃-2-基)丙-1-酮4a通过1,6-二氧基双自由基中间体形成,而热解主要得到1,5-di(p -甲氧基苯基)戊-1,5-二酮5a和1,4-二(对甲氧基苯基)丁-1,4-二酮8a。
Electron-transfer induced intramolecular [2 + 2] cyloaddition of 2,6-diarylhepta-1,6-dienes
摘要:
Intramolecular [2 + 2] cycloaddition of 2,6-diaryl-1.6-heptadienes 1a-c to bicycloheptanes 2 can be induced by electron-transfer photosensitization with 9,10-dicyanoanthracene. A stepwise mechanism involving cyclic 1,4-cation radical 3 has been proposed based on the trapping experiments.