反应详情

Concentrated sulfuric acid (1.5 ml.) is added to a slurry of 6,7-dimethoxy-2-aminoquinoline-3-carboxamide (5.0 g., 0.02 mole) and acetic anhydride (40 ml). The slurry dissolves to give a dark orange solution from which a heavy yellow precipitate separates. Acetic anhydride (10 ml.) is added to facilitate stirring and heating continued for an additional 75 minutes. The mixture is cooled, water (50 ml.) added and the resulting solution made alkaline with 5N sodium hydroxide (225 ml.). It is chilled, the precipitate collected by filtration and air-dried. The yellow solid is recrystallized from ethanol. Yield = 2.37 g., M.P. 300° -302° (dec.).

1. dissolutionThe slurry dissolves
2. customto give a dark orange solution from which a heavy yellow precipitate separates
3. temperatureheating
4. temperatureThe mixture is cooled
5. temperatureIt is chilled
6. filtrationthe precipitate collected by filtration
7. customair-dried
8. customThe yellow solid is recrystallized from ethanol