Reacción #574424

Ecuación de reacción

(1-ethoxyethylidene)malononitrile

2-methylcyclopentylhydrazine hydrochloride

sodium methoxide

→

1-(2-methylcyclopentyl)-3-methyl-5-amino-1H-pyrazole-4-carbonitrile

Rendimiento 56.2%

Disolventes

ethanol

Condiciones de reacción

Tratamiento posterior

1. 1
   TemperaturaThe reaction mixture was heated
2. 2
   Temperaturato reflux
3. 3
   workup.STIRRINGwas stirred for 5 hours
4. 4
   OtroThe solvent was removed in vacuo
5. 5
   Otrothe residue was partitioned between chloroform and water
6. 6
   OtroThe organic layer was separated
7. 7
   Extracciónthe aqueous layer was extracted with chloroform three times
8. 8
   LavadoThe combined organic layers were washed with brine
9. 9
   Secadodried over anhydrous MgSO4
10. 10
    Otrothe solvent was removed in vacuo
11. 11
    LavadoThe residue was washed with ether

Procedimiento

To a solution of 2-methylcyclopentylhydrazine hydrochloride (7.4 g, 48.8 mmol) in ethanol (100 ml) was added sodium methoxide (2.6 g, 48.8 mmol). The resulting white suspension was stirred for 10 minutes at room temperature and then (1-ethoxyethylidene)malononitrile (6.7 g, 48.8 mmol) was added. The reaction mixture was heated to reflux and was stirred for 5 hours. The solvent was removed in vacuo and the residue was partitioned between chloroform and water. The organic layer was separated and the aqueous layer was extracted with chloroform three times. The combined organic layers were washed with brine, then dried over anhydrous MgSO4. The solution was passed through a plug of silica gel and the solvent was removed in vacuo. The residue was washed with ether to afford 5.6 g (56%) of 1-(2-methylcyclopentyl)-3-methyl-5-amino-1H-pyrazole-4-carbonitrile as a white powder, m.p. 158°-159° C.

Fuente