反应详情

Acetylsalicylic acid (1.8 g.) was converted to its acid chloride by conventional method using thionyl chloride and dissolved in acetone (30 ml.). 4-Amino-2,6-dichloroanisole (2.13 g.) with N,N-dimethylaniline (1.27 ml.) was dissolved in acetone (25 ml.) to which, with stirring in the cold at 0°-10° C., the above acetone solution of acetylsalicyloyl chloride was added dropwise over 20-30 minutes. Reaction continued for 1-2 hours, then the solution was evaporated to dryness under reduced pressure, the residue being put in sodium hydroxide solution and gently agitated for 1-2 hours for cleavage of the acetyl group. After reaction was complete the solution was made acidic by the addition of 2 N hydrochloric acid and the precipitate which formed was collected by filtration and recrystallized from aqueous acetone to give needle-like crystals (2.0 g.) of 3,5-dichloro-2'-hydroxy-4-methoxybenzanilide. Yield 64%. The melting point of the product is 226° - 228° C.

1. customReaction
2. customthe solution was evaporated to dryness under reduced pressure
3. stirringgently agitated for 1-2 hours for cleavage of the acetyl group
4. customAfter reaction
5. customthe precipitate which formed
6. filtrationwas collected by filtration
7. customrecrystallized from aqueous acetone