反应详情

6.40 ml of acetic anhydride was added to 5.00 g (32.00 mM) of 3-fluoro-4-hydroxybenzoic acid. Under stirring at room temperature, two drops of concentrated sulfuric acid was added thereto (the mixture solidified as soon as the concentrated sulfuric acid was added), followed by heat-stirring for 10 minutes at 107°-111° C. on an oil bath (the mixture became transparent and melted by heating). After the reaction, the reaction mixture was poured into 150 ml of iced water to precipitate a crystal. The crystal was recovered by filtration and recrystallized from 20 ml of methanol to obtain 5.04 g of 4-acetoxy-3-fluorobenzoic acid (Yield: 79.4%).

1. additionwas added),
2. stirringby heat-stirring for 10 minutes at 107°-111° C. on an oil bath (the mixture
3. temperatureby heating)
4. customAfter the reaction
5. customto precipitate a crystal
6. filtrationThe crystal was recovered by filtration
7. customrecrystallized from 20 ml of methanol