反应详情

To a stirred mixture of 4-benzoyl-3-n-butoxy-5-nitrobenzoic acid (5.1 g), pyridine (25 ml), and water (25 ml), sodium dithionite (10.2 g) is added in portions. The mixture is heated on a steam bath for 1 hour and is then evaporated in vacuo. The remaining material is dissolved in water (about 50 ml) and the solution is acidified with conc. hydrochloric acid (about 15 ml). After cooling, the resulting precipitate is collected by filtration and washed with water. After drying and recrystallization twice from ethanol, 5-amino-4-benzoyl-3-n-butoxybenzoic acid is obtained with a melting point of 202.5° -203.5° C.

1. additionis added in portions
2. temperatureThe mixture is heated on a steam bath for 1 hour
3. customis then evaporated in vacuo
4. dissolutionThe remaining material is dissolved in water (about 50 ml)
5. temperatureAfter cooling
6. filtrationthe resulting precipitate is collected by filtration
7. washwashed with water
8. customAfter drying
9. customrecrystallization twice from ethanol