反应详情

温度

20 °C

115 g of 3-(N-acetylamino)aniline-4-sulfonic acid in 430 ml of water and 70 g of formic acid were boiled under reflux for 7 hours. The mixture was cooled to 20° C. and its pH then adjusted to 12 with caustic soda solution. 75 g of dimethyl sulfate were then added, and after 40 minutes the pH was adjusted to -0.5 with hydrochloric acid. The mixture was heated under reflux for 3 hours and then salted out with 150 g of sodium chloride. The pH was adjusted to 1.0 with caustic soda solution, and the precipitated 3-(N-methylamino)aniline-4-sulfonic acid was isolated by filtration.

1. temperatureunder reflux for 7 hours
2. temperatureThe mixture was heated
3. temperatureunder reflux for 3 hours