Ring-chain tautomerism in the products of the reaction between 5-substituted furfurylamines and anhydrides of α,β-unsaturated carboxylic acids
作者:Fedor I. Zubkov、Victor D. Golubev、Vladimir P. Zaytsev、Olga V. Bakhanovich、Evgeniya V. Nikitina、Victor N. Khrustalev、Rinat R. Aysin、Tatiana V. Timofeeva、Roman A. Novikov、Aleksey V. Varlamov
DOI:10.1007/s10593-016-1868-9
日期:2016.4
The reactions of 5-substituted furfurylamines with anhydrides of α,β-unsaturated carboxylic acids (acryloyl chloride and maleic anhydride) were studied. The first step of the reaction mechanism involved acylation of furfurylamine nitrogen atom, followed by a stereospecific, spontaneous intramolecular Diels–Alder reaction at the furan ring of the N-furfurylamide intermediates. When the starting materials
研究了5-取代的糠胺与α,β-不饱和羧酸(丙烯酰氯和马来酸酐)的酸酐的反应。反应机理的第一步涉及糠胺氮原子的酰化,然后在N-糠酰胺中间体的呋喃环上发生立体有择的,自发的分子内Diels-Alder反应。当起始材料是5-烷基取代的furfurylamines,预期的1-氧代2,3,7,7a -六氢- 1 H ^最多得到98%-3a,6- epoxyisoindoles或相应的7-羧酸产量。5-芳基取代的糠胺与马来酸酐的酰化导致N-糠基马来酰胺,通过分子内[4 + 2]环加成反应形成的加合物在溶液中形成动态平衡,即3a,6-环氧异吲哚-7-羧酸,已通过NMR光谱证明。X射线结构分析结果表明,这些混合物以环状互变异构体的形式结晶。