反应详情

An aqueous 6N solution of HCl (40 mL) was cautiously added with stirring to a solution of 3 (20 g, 68 mmol) in ethanol (80 mL). After heating under reflux for 3 h, the reaction mixture was evaporated to dryness in vacuo and the residue was dissolved in water. The pH of the solution was adjusted to 8-9 using 1N aq. NH4OH. After stirring for 1 h, the white solid that gradually precipitated was collected by filtration. The filter cake was washed with ice-cold water, dried under vacuum, and recrystallized from hot ethanol to give to give 4-amino-N-phenyl-benzenesulfonamide (4) (also called 207-33 or LED207) (10.9 g, 65%) as a white solid, mp 194-195° C. 1H NMR (CD3COCD3, 300 MHz) δ 8.64 (br s, 1H), 7.50-7.45 (m, 2H), 7.25-7.18 (m, 4H), 7.04-6.98 (m, 1H), 6.67-6.62 (m, 2H), 5.44 (br s, 2H); 13C NMR (CD3COCD3, 75 MHz) δ 152.9, 138.8, 129.3 (2C), 129.1 (2C), 126.3, 124.0, 120.5 (2C), 113.1 (2C).

1. temperatureAfter heating
2. temperatureunder reflux for 3 h
3. customthe reaction mixture was evaporated to dryness in vacuo
4. dissolutionthe residue was dissolved in water
5. customthe white solid that gradually precipitated
6. filtrationwas collected by filtration
7. washThe filter cake was washed with ice-cold water
8. customdried under vacuum
9. customrecrystallized from hot ethanol
10. customto give