4-Morpholinomethyl-2H-pyran-3(6H)-ones 3 and 8 were prepared directly from 6-methoxy-2H-pyran-3(6H)-one (1) and its epoxide 4 by treatment with morpholine and aqueous 37% formalin in methanol in 70–88% yield. The mechanisms of the reaction have been discussed on the basis of the intermediates 5,6-dimethoxytetrahydropyran-3-one (2), 2,6-dimethoxy-5-hydroxytetrahydropyran-3-one (5), 2,6-dimethoxy-2H-pyran-3(6H)-one
4-Morpholinomethyl-2H-pyran-3(6H)-ones 3 和 8 直接由 6-甲氧基-
2H-吡喃-3(6H)-one (1) 及其
环氧化物 4 用吗啉和 37%
水溶液处理制备
福尔马林的
甲醇溶液,产率为 70-88%。反应机理已在中间体 5,6-二甲氧基
四氢吡喃-3-酮 (2)、2,6-二甲氧基-5-羟基
四氢吡喃-3-酮 (5)、2,6-二甲氧基-酮的基础上进行了讨论。
2H-吡喃-3(6H)-one (6) 和 2,5,6-
三甲氧基四氢吡喃-3-one (7)。