反应详情

温度

25 °C

To a solution of 2-(4-aminophenyl)ethane sulfonic acid methylamide (50 g) in dichloromethane (500 ml), a 10% solution of sodium bicarbonate (500 ml) was added at 25° C. so as to obtain a biphasic reaction mass. Iodine crystals were added slowly maintaining the temperature below 30° C. The mixture was agitated at 25° C. for about an hour and cooled to 10-15° C. The excess of iodine content in the mixture was neutralized with saturated sodium metabisulphite solution and a solution of 2-(4-amino-3-iodo-phenyl)-ethanesulfonic acid methylamide (75 g) in dichloromethane (750 ml) was added followed by dropwise addition of 50% solution of acetic anhydride in dichloromethane (300 ml) maintaining the temperature of 25° C. The reaction mass was stirred for about 90 minutes and layers were separated. The organic layer was washed with water, dried and distilled under vacuum to obtain a residue. The residue was stirred in heptane (500 ml), filtered and dried under vacuum at 50-55° C. to obtain the title compound. (Yield: 85 g, HPLC Purity: 99%)

1. customto obtain a biphasic reaction mass
2. temperaturemaintaining the temperature below 30° C
3. temperaturecooled to 10-15° C
4. temperaturemaintaining the temperature of 25° C
5. stirringThe reaction mass was stirred for about 90 minutes
6. customlayers were separated
7. washThe organic layer was washed with water
8. customdried
9. distillationdistilled under vacuum
10. customto obtain a residue
11. filtrationfiltered
12. customdried under vacuum at 50-55° C.