Reaktion #574424

Reaktionsgleichung

(1-ethoxyethylidene)malononitrile

2-methylcyclopentylhydrazine hydrochloride

sodium methoxide

→

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

Ausbeute 56.2%

Lösungsmittel

ethanol

Reaktionsbedingungen

Aufarbeitung

1. 1
   TemperaturThe reaction mixture was heated
2. 2
   Temperaturto reflux
3. 3
   workup.STIRRINGwas stirred for 5 hours
4. 4
   SonstigeThe solvent was removed in vacuo
5. 5
   Sonstigethe residue was partitioned between chloroform and water
6. 6
   SonstigeThe organic layer was separated
7. 7
   Extraktionthe aqueous layer was extracted with chloroform three times
8. 8
   WaschenThe combined organic layers were washed with brine
9. 9
   Trocknendried over anhydrous MgSO4
10. 10
    Sonstigethe solvent was removed in vacuo
11. 11
    WaschenThe residue was washed with ether

Vorschrift

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.

Quelle