反应详情

A solution of 20.0 g of 5-aminosalicylic acid, 250 ml of methanol and 10 ml of concentrated sulfuric acid is refluxed overnight. The reaction mixture is cooled, made alkaline with dilute aqueous sodium carbonate solution and concentrated. The resulting solid is separated and washed with water. The solid is then washed with ether, and the ether is evaporated to dryness yielding a brown solid. The aqueous filtrate above is extracted with ether, the extract is dried over anhydrous sodium sulfate, and evaporated yielding a brown solid. The solids are combined and recrystallized from ether to afford 10.7 g of 5-aminosalicylic acid methyl ester.

1. temperatureThe reaction mixture is cooled
2. concentrationconcentrated
3. customThe resulting solid is separated
4. washwashed with water
5. washThe solid is then washed with ether
6. customthe ether is evaporated to dryness
7. customyielding a brown solid
8. extractionThe aqueous filtrate above is extracted with ether
9. dry with materialthe extract is dried over anhydrous sodium sulfate
10. customevaporated
11. customyielding a brown solid
12. customrecrystallized from ether