Реакция #4014

Уравнение реакции

ethacrolein

diethyl 3-chloro-2-oxo-butanedioate

ammonium sulfamate

→

title product

Выход 86.0%

diethyl 5-ethylpyridine-2,3-dicarboxylate

Выход 86.0%

Растворители

ethanol

Условия реакции

Обработка

1. 1
   Температураis heated
2. 2
   Температураat reflux
3. 3
   Другоеthe solvent removed by distillation under reduced pressure
4. 4
   workup.ADDITIONThe residue is treated with water
5. 5
   Экстракцияextracted with ethyl acetate
6. 6
   ДругоеThe organic phase is separated
7. 7
   Концентрированиеconcentrated in vacuo
8. 8
   Другоеthe residue purified by column chromatography on silica gel using 4:1 hexane-ethyl acetate as the eluent

Методика

A stirred mixture of ethacrolein, (4.2 g, 0.05 mol), diethyl 3-chloro-2-oxo-butanedioate, (11.2 g, 0.05 mol) and ammonium sulfamate, (15.4 g, 0.135 mol) in ethanol (37 mL) is heated at reflux. After 15 hours the mixture is cooled to room temperature and the solvent removed by distillation under reduced pressure. The residue is treated with water and extracted with ethyl acetate. The organic phase is separated and concentrated in vacuo and the residue purified by column chromatography on silica gel using 4:1 hexane-ethyl acetate as the eluent to give 10.8 g (75% yield) of the title product as an oil which is shown to be 95% pure by a gas chromatography assay.

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