反应详情

温度

40 °C

A solution of 2.0 g of potassium permanganate in 10 ml of water was added dropwise to a mixture of 1.2 g of 4-bromo-1-(3-chloro-4-pyridinyl)-1H-pyrrole-2-carbaldehyde and 30 ml of acetone while the mixture was maintained at 40° C. The resulting mixture was stirred at 60° C. for 1 hour. A precipitate was filtered off to obtain a filtrate. The filtrate was adjusted to pH 10-12 by an addition of a 2N aqueous sodium hydroxide solution, and then washed with chloroform two times. The aqueous layer was adjusted to around pH 3 by an addition of 2N hydrochloric acid, and then extracted with ethyl acetate two times. The organic layers were combined, washed successively with water and an aqueous saturated sodium chloride solution, dried over anhydrous sodium sulfate, and concentrated under reduced pressure to obtain 0.43 g of 4-bromo-1-(3-chloro-4-pyridinyl)-1H-pyrrole-2-carboxylic acid of the formula:

1. filtrationA precipitate was filtered off
2. customto obtain a filtrate
3. washwashed with chloroform two times
4. additionThe aqueous layer was adjusted to around pH 3 by an addition of 2N hydrochloric acid
5. extractionextracted with ethyl acetate two times
6. washwashed successively with water
7. dry with materialan aqueous saturated sodium chloride solution, dried over anhydrous sodium sulfate
8. concentrationconcentrated under reduced pressure