Reaktion #367644

Reaktionsgleichung

tert-Butylhydrazine hydrochloride

α-acetyl-α-(dimethylaminomethylene)acetic acid, ethyl ester

→

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

Ausbeute 88.0%

Lösungsmittel

ethanol

Reaktionsbedingungen

Aufarbeitung

1. 1
   Sonstigethe resulting reaction mixture
2. 2
   Temperaturwas refluxed for two hours
3. 3
   TemperaturThe reaction mixture was then cooled
4. 4
   Sonstigethe solvent was removed in vacuo
5. 5
   Waschenwashed with water
6. 6
   Waschenwashed with saturated sodium bicarbonate
7. 7
   Waschenwashed with saturated brine
8. 8
   Sonstigedried
9. 9
   Filtrationfilter paper
10. 10
    SonstigeThe solvent was then removed in vacuo
11. 11
    workup.DISTILLATIONThe residue was distilled at 110° C. at 1.2 mm mercury pressure

Vorschrift

tert-Butylhydrazine hydrochloride (33.6 grams, 0.27 mole) and α-acetyl-α-(dimethylaminomethylene)acetic acid, ethyl ester (50 grams, 0.27 mole) were added to 150 ml of ethanol and the resulting reaction mixture was refluxed for two hours. The reaction mixture was then cooled, and the solvent was removed in vacuo. The residue was taken up in 300 ml of ether, washed with water, washed with saturated sodium bicarbonate, washed with saturated brine, and dried using sodium sulfate and filter paper. The solvent was then removed in vacuo. The residue was distilled at 110° C. at 1.2 mm mercury pressure to provide 49.7 grams of 5-methyl-1-tert-butyl-1H-pyrazole-4-carboxylic acid, ethyl ester. Yield 88.0%.

Quelle