反応 #792180

反応方程式

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

収率 77.0%

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

収率 77.0%

溶媒

acetic acid

acetic acid

反応条件

後処理

1. 1
   その他was removed under reduced pressure
2. 2
   その他The mixture was partitioned between saturated aqueous sodium carbonate solution (100 mL) and ethyl acetate (100 mL)
3. 3
   抽出The aqueous layer was further extracted with ethyl acetate (100 mL)
4. 4
   その他The combined organic extracts were dried
5. 5
   その他evaporated

実験手順

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).

出典