反应详情

2,6-Dibromo-4-aminophenol (0.6 g.) was dissolved in acetone (30 ml.) to which was added pyridine (0.32 ml.). Then dropwise and with stirring the solution was added to an acetone solution (10 ml.) containing acetylsalicyloyl chloride which was prepared from acetylsalicylic acid (0.38 g.). Then the reactant solution was evaporated to dryness under reduced pressure to give a residue which was dissolved in ethyl acetate. After washing first with water and then with 1 N hydrochloric acid, the solution was evaporated under reduced pressure to remove ethyl acetate. The residues were redissolved in a mixture of methanol and 2 N sodium hydroxide (10 ml. each). Stirring this solution for several hours and acidifying with 2 N hydrochloric acid precipitated the product which was recrystallized from aqueous methanol to give light brown crystals of 3,5-dibromo-2',4-dihydroxybenzanilide (0.88 g.). Yield: 78%. The compound melts at 182°-187° C.

1. customThen the reactant solution was evaporated to dryness under reduced pressure
2. customto give a residue which
3. washAfter washing first with water
4. customwith 1 N hydrochloric acid, the solution was evaporated under reduced pressure
5. customto remove ethyl acetate
6. dissolutionThe residues were redissolved in a mixture of methanol and 2 N sodium hydroxide (10 ml
7. stirringStirring this solution for several hours
8. customprecipitated the product which
9. customwas recrystallized from aqueous methanol