Reacción #41104

Ecuación de reacción

t-butylhydrazine hydrochloride salt

ethyl (ethoxymethylene)-cyanoacetate

sodium acetate

→

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

Rendimiento 77.0%

Disolventes

ethanol

Condiciones de reacción

Tratamiento posterior

1. 1
   Temperaturarefluxed for 16 hours
2. 2
   ExtracciónThe separated aqueous phase was extracted three times with dichloromethane
3. 3
   LavadoThe combined organic phases were washed successively with water and saturated brine solution
4. 4
   Secadodried with sodium sulfate
5. 5
   OtroThe solvent was removed in vacuo

Procedimiento

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%).

Fuente