Reaktion #792181

Reaktionsgleichung

Potassium hydroxide

ethyl 1-(3-chloro-2-pyridinyl)-3-(trifluoromethyl)-1H-pyrazole-5-carboxylate

product

ethyl 1-(3-chloro-2-pyridinyl)-3-(trifluoromethyl)-1H-pyrazole-5-carboxylate

→

product

Ausbeute 93.0%

1-(3-chloro-2-pyridinyl)-3-(trifluoromethyl)-1H-pyrazole-5-carboxylic acid

Ausbeute 93.0%

Lösungsmittel

water

ethanol

Reaktionsbedingungen

Aufarbeitung

1. 1
   Sonstigethe solvent was removed under reduced pressure
2. 2
   workup.DISSOLUTIONthe mixture was dissolved in water (40 mL)
3. 3
   WaschenThe solution was washed with ethyl acetate (20 mL)
4. 4
   Extraktionwas extracted with ethyl acetate (3×20 mL)
5. 5
   SonstigeThe combined extracts were dried
6. 6
   Sonstigeevaporated
7. 7
   Sonstigeto give

Vorschrift

Potassium hydroxide (0.5 g, 85%, 2.28 mmol) in water (1 mL) was added to ethyl 1-(3-chloro-2-pyridinyl)-3-(trifluoromethyl)-1H-pyrazole-5-carboxylate (i.e. the product of Step D) (0.66 g, 2.07 mmol) in ethanol (3 mL). After about 30 minutes, the solvent was removed under reduced pressure, and the mixture was dissolved in water (40 mL). The solution was washed with ethyl acetate (20 mL). The aqueous layer was acidified with concentrated hydrochloric acid and was extracted with ethyl acetate (3×20 mL). The combined extracts were dried and evaporated to give the product as a solid (0.53 g, 93% yield), m.p. 178-179° C. (after crystallization from hexanes-ethyl acetate).

Quelle