Réaction #792180

Équation de réaction

ethyl 1-(3-chloro-2-pyridinyl)-4,5-dihydro-5-hydroxy-3-(trifluoromethyl)-1H-pyrazole-5-carboxylate

product

ethyl 1-(3-chloro-2-pyridinyl)-4,5-dihydro-5-hydroxy-3-(trifluoromethyl)-1H-pyrazole-5-carboxylate

→

product

Rendement 77.0%

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

Rendement 77.0%

Solvants

acetic acid

acetic acid

Conditions de réaction

Traitement

1. 1
   Autrewas removed under reduced pressure
2. 2
   AutreThe mixture was partitioned between saturated aqueous sodium carbonate solution (100 mL) and ethyl acetate (100 mL)
3. 3
   ExtractionThe aqueous layer was further extracted with ethyl acetate (100 mL)
4. 4
   AutreThe combined organic extracts were dried
5. 5
   Autreevaporated

Mode opératoire

Sulfuric acid (concentrated, 2 drops) was added to ethyl 1-(3-chloro-2-pyridinyl)-4,5-dihydro-5-hydroxy-3-(trifluoromethyl)-1H-pyrazole-5-carboxylate (i.e. the product of Step C) (1 g, 2.96 mmol) in acetic acid (10 mL) and the mixture was warmed to 65° C. for about 1 hour. The mixture was allowed to cool to 25° C. and most of the acetic acid was removed under reduced pressure. The mixture was partitioned between saturated aqueous sodium carbonate solution (100 mL) and ethyl acetate (100 mL). The aqueous layer was further extracted with ethyl acetate (100 mL). The combined organic extracts were dried and evaporated to give the product as an oil (0.66 g, 77% yield).

Source