Recyclization of (2-Aminophenyl)bis(5-<i>tert</i>-butyl-2-furyl)methanes into Indole Derivatives: Unusual Dependence on Substituent at Nitrogen Atom
作者:Alexander Butin、Sergey Smirnov、Fatima Tsiunchik、Maxim Uchuskin、Igor Trushkov
DOI:10.1055/s-2008-1067248
日期:2008.9
furan ring opening proceed with heating. These data and results of control experiments showed that the reaction mechanism consists of three successive steps: recyclization itself, deacylation of the resulting N-acylindole, and furan ring opening in N-unsubstituted 3-(2-furyl)indoles. The last step can be realized for N-unsubstituted indoles only, but the furan ring is stable for N-acylindoles. This was
研究了(2-氨基苯基)双(5-叔丁基-2-呋喃基)甲烷在酸性条件下的再循环。发现这些底物的反应程度取决于苯胺部分氮原子上的取代基。N-甲苯磺酰基衍生物转化为相应的3-(5-叔丁基-2-呋喃基)-2-(4,4-二甲基-3-氧代戊基)-1-甲苯磺酰基-1H-吲哚。在 N-未取代底物的情况下,吲哚形成之后呋喃开环,产生 3-(5,5-二甲基-1,4-二氧己基)-2-(4,4-二甲基-3-氧代戊基)-1H-吲哚。从N-乙酰基衍生物获得相同的产物。然而,N-苯甲酰基类似物的行为取决于反应条件:在室温下形成 1-苯甲酰基-3-(5-叔丁基-2-呋喃基)-1H-吲哚,但进行脱苯甲酰基化和呋喃开环带加热。这些数据和对照实验的结果表明,反应机理包括三个连续的步骤:再循环本身、所得 N-酰基吲哚的脱酰化和 N-未取代的 3-(2-呋喃基)吲哚中的呋喃开环。只有 N-未取代的吲哚才能实现最后一步,但呋喃环对于