Synthesis of stable azomethine ylides by the rearrangement of 1,3-dipolar cycloadducts of 3,4-dihydroisoquinoline-2-oxides with DMAD
作者:Necdet Coşkun、Selen Tunçman
DOI:10.1016/j.tet.2005.11.040
日期:2006.2
corresponding 3,4-dihydroisoquinoline-2-oxides. Treatment of these cyclic nitrones with DMAD in toluene at room temperature gave the corresponding isoxazolo[3,2-a]isoquinolines. These compounds were heated in toluene at reflux to give the corresponding ylides in high yields (Method A). The effect of the substituents on the rate of the rearrangement of such compounds prompted us to discuss a new mechanism involving
根据一锅法制备1-芳基-6,7-二甲氧基-1,2,3,4-四氢异喹啉,该过程涉及2-(3,4-二甲氧基苯基)-乙胺与芳族醛在TFA中回流反应。 。在室温下用甲醇中的H 2 O 2 -WO 4 2-处理四氢异喹啉,得到相应的3,4-二氢异喹啉-2-氧化物。在室温下用DMAD在甲苯中处理这些环状硝酮,得到相应的异恶唑并[3,2- a]异喹啉。将这些化合物在甲苯中加热回流,以高收率得到相应的酰化物(方法A)。取代基对这类化合物重排速率的影响促使我们讨论了涉及连续C–C键杂合和1,3-σ位移的新机理。一锅反应包括在回流的甲苯中用等摩尔量的DMAD处理硝酮,也得到了叶立德(方法B)。通过光谱方法和元素分析阐明了所制备化合物的结构。