Reaction #792181

Reaction equation

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

Yield 93.0%

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

Yield 93.0%

Solvents

water

ethanol

Conditions

Workup

1. 1
   Otherthe solvent was removed under reduced pressure
2. 2
   workup.DISSOLUTIONthe mixture was dissolved in water (40 mL)
3. 3
   WashThe solution was washed with ethyl acetate (20 mL)
4. 4
   Extractionwas extracted with ethyl acetate (3×20 mL)
5. 5
   OtherThe combined extracts were dried
6. 6
   Otherevaporated
7. 7
   Otherto give

Procedure

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).

Source