Glycerol is applied as a green, biodegradable and reusable promoting medium for one-pot three component synthesis of 4H-pyrans under catalyst-free conditions. A broad range of substrates including aromatic and heteroaromatic aldehydes, isatine derivatives, acenaphthenequinone and ninehydrine are condensed with carbonyl compounds possessing a reactive α-methylene group and alkylmalonates. All reactions are completed in short times, and the products are obtained in good to excellent yields. The reaction medium could be recycled and reused several times without any loss of efficiency.
甘油作为绿色、
生物可降解且可重复利用的促进介质,在无催化剂条件下用于一锅法三组分合成
4H-吡喃。广泛的一系列底物,包括芳香和杂环醛、
吲哚醌衍
生物、
苊醌和九氢
吲哚,与具有活性α-亚甲基的羰基化合物及烷基
丙二酸酯进行缩合反应。所有反应均在短时间内完成,产物收率良好至优异。反应介质可回收并重复使用多次,效率无任何损失。