반응 #1532720

반응 방정식

sodium hydroxide

Water

ethyl 1-(3-chloro-2-pyridinyl)-2,3-dihydro-3-oxo-1H-pyrazole-5-carboxylate

product

Ethyl 1-(3-chloro-2-pyridinyl)-2,3-dihydro-3-oxo-1H-pyrazole-5-carboxyate

water

→

title compound

1-(3-Chloro-2-pyridinyl)-2,3-dihydro-3-oxo-1H-pyrazole-5-carboxylic acid

용매

methanol

반응 조건

후처리

1. 1
   추출the reaction mixture was extracted with ethyl ether, which
2. 2
   추출extracted with ethyl acetate (50 mL)
3. 3
   추출The ethyl acetate extract
4. 4
   세척was washed with water (20 mL) and brine (20 mL)
5. 5
   건조dried over magnesium sulfate
6. 6
   농축concentrated

실험 절차

To a stirred solution of ethyl 1-(3-chloro-2-pyridinyl)-2,3-dihydro-3-oxo-1H-pyrazole-5-carboxylate (i.e. the product of Step B) (1.0 g, 3.7 mmol) in methanol (15 mL) was added water (3 mL). An aqueous solution of sodium hydroxide (50%, 1.0 g, 12.5 mmol) was added dropwise, and the reaction mixture was stirred at room temperature for 3 hours, during which time the reaction mixture turned a clear yellow. Water (20 mL) was added and the reaction mixture was extracted with ethyl ether, which was discarded. The aqueous phase was acidified to pH 2 using concentrated hydrochloric acid and then extracted with ethyl acetate (50 mL). The ethyl acetate extract was washed with water (20 mL) and brine (20 mL), dried over magnesium sulfate and concentrated to give the title compound, isolated as a white solid (0.76 g).

출처