Synthesis and Structure of Esterification Products of 6-aryl-1,2,3,6,7,7a-hexahydro-3а,6-epoxyisoindole-7-carboxylic Acids
作者:Maryana А. Nadirova、Kuz’ma M. Pokazeev、Irina А. Kolesnik、Pavel V. Dorovatovskii、Nikolay А. Bumagin、Vladimir I. Potkin
DOI:10.1007/s10593-019-02528-z
日期:2019.8
6-epoxyisoindole-7-carboxylic acids (the cyclic form), which in solution are in dynamic equilibrium with N-furfurylmaleinamides (the open form). During the esterification of these tautomeric mixtures with methanol in the presence of a catalytic amount of sulfuric acid, methyl esters of 5-aryl-7a-hydroxy-7-methoxy-3-oxo-2,3,3a,4,7,7a-hexahydro-1H-isoindole-4-carboxylic acids, unexpected cleavage products
发现5-芳基糠胺与马来酸酐的反应导致形成6-芳基-3a,6-环氧异吲哚-7-羧酸(环状形式),其在溶液中与N-糠基马来酰胺动态平衡(开放形式)。在催化量的硫酸存在下这些互变异构混合物与甲醇的酯化过程中,5-芳基-7a-羟基-7-甲氧基-3-氧代-2,3,3a,4,7,7a的甲酯非对映异构地形成环状形式的3a,6-氧代桥的意外的裂解产物-六氢-1 H-异吲哚-4-羧酸。通过X射线结构分析确认了所得产物的结构。