Coumarin-enaminoester Adducts: Structure Corrections (X-ray) and Some Novel Transformations. Synthesis of Annulated Tricyclic 2-Pyridones
作者:Ivo C. Ivanov、Lyubomir D. Raev、Wolfgang Frey
DOI:10.1055/s-2004-829081
日期:——
By means of X-ray crystallographic analysis the correct structure of all three types of stable coumarin-enaminoester adducts 6, 10 and 11 and the corresponding spontaneous multistep heterocyclizations of ANRORC-type are reported. The initially formed adducts 3-5 undergo lactone ring opening as well as, in many cases, spontaneous transannular intramolecular Michael addition, to give 6, 10 and 11. A
通过 X 射线晶体学分析,报告了所有三种稳定香豆素-烯氨基酯加合物 6、10 和 11 的正确结构以及相应的 ANRORC 型自发多步杂环化。最初形成的加合物 3-5 经历内酯开环以及在许多情况下自发的跨环分子内迈克尔加成,得到 6、10 和 11。丙二酸乙酯 12 与 3-取代香豆素 1 的经典迈克尔加成,然后是内酯开环得到 13 作为最终产物。