Реакция #41104

Уравнение реакции

t-butylhydrazine hydrochloride salt

ethyl (ethoxymethylene)-cyanoacetate

sodium acetate

→

5-amino-1-tert-butyl-1H-pyrazole-4-carboxylic acid ethyl ester

Выход 77.0%

Растворители

ethanol

Условия реакции

Обработка

1. 1
   Температураrefluxed for 16 hours
2. 2
   ЭкстракцияThe separated aqueous phase was extracted three times with dichloromethane
3. 3
   ПромывкаThe combined organic phases were washed successively with water and saturated brine solution
4. 4
   Сушкаdried with sodium sulfate
5. 5
   ДругоеThe solvent was removed in vacuo

Методика

A solution containing t-butylhydrazine hydrochloride salt (10 g, 80.3 mmol), ethyl (ethoxymethylene)-cyanoacetate (13.6 g, 80.4 mmol), and anhydrous sodium acetate (8.2 g, 100 mmol) in 100 mL ethanol was stirred and refluxed for 16 hours. The solution was poured into ice-water. The separated aqueous phase was extracted three times with dichloromethane. The combined organic phases were washed successively with water and saturated brine solution and dried with sodium sulfate. The solvent was removed in vacuo to give 5-amino-1-tert-butyl-1H-pyrazole-4-carboxylic acid ethyl ester (13 g, 77%).

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