反应详情

3-Bromo-5-aminosalicylic acid (0.73 g.) was dissolved in acetone (30 ml.) and pyridine (0.4 ml.) to which an acetone (14 ml.) solution containing acetyl-salicyloyl chloride (prepared from 0.53 g. of acetyl-salicylic acid) was added dropwise with stirring. After reaction the solution was evaporated to dryness under reduced pressure and the residue was dissolved in ethyl acetate. After washing the solution with water and 1 N hydrochloric acid successively, the ethyl acetate was evaporated off under reduced pressure, yielding a residue which was redissolved in a mixture of methanol and 2 N sodium hydroxide (14 ml. each). After stirring the solution for several hours and then acidifying with 2 N hydrochloric acid solution, a precipitate was formed, collected and crystallized from aqueous methanol to give light brown crystals (0.90 g.) of 5-bromo-3-carboxy-2',4-dihydroxybenzanilide.

1. additionwas added dropwise
2. customAfter reaction the solution
3. customwas evaporated to dryness under reduced pressure
4. dissolutionthe residue was dissolved in ethyl acetate
5. washAfter washing the solution with water and 1 N hydrochloric acid successively
6. customthe ethyl acetate was evaporated off under reduced pressure
7. customyielding a residue which
8. stirringAfter stirring the solution for several hours
9. customa precipitate was formed
10. customcollected
11. customcrystallized from aqueous methanol