Janza Birgit, Studer Armido
Organisch-Chemisches Institut, Westfälische Wilhelms-Universität Münster, Corrensstrasse 40, 48149 Münster, Germany.
Org Lett. 2006 Apr 27;8(9):1875-8. doi: 10.1021/ol0604421.
[reaction: see text] An efficient tandem radical process comprising a thermal alkoxyamine homolysis, an isonitrile trapping reaction, a 5-exo-trig cyclization, and a homolytic aromatic substitution leads to substituted dihydroquinolines. Depending on the substituent R(1), oxidation to dihydro-1H-cyclopenta[b]quinolines (for R(1) = aryl) or tautomerization to tetrahydro-1H-cyclopenta[b]quinolines (for R(1) = CO(2)Me, CN) occurs. The heterocycles are obtained in moderate to good yields. Upon using microwave-induced heating, the reaction time can be shortened from 3 days to 30 min.
[反应：见正文] 一个高效的串联自由基过程，包括热引发的烷氧基胺均裂、异腈捕获反应、5-外向-三取代环化反应和均裂芳香取代反应，可生成取代的二氢喹啉。根据取代基R(1)的不同，会发生氧化生成二氢-1H-环戊并[b]喹啉（当R(1)=芳基时）或互变异构生成四氢-1H-环戊并[b]喹啉（当R(1)=CO₂Me、CN时）。这些杂环化合物的产率适中至良好。使用微波诱导加热时，反应时间可从3天缩短至30分钟。
