2-bromo-5-nitrobenzenesulfonamide synthesis

Yield:-

Reaction Conditions:

with ammonium hydroxide in 1,4-dioxane at 20;

Steps:

2-Bromo-5-nitrobenzenesulfonamide

2-Bromo-5-nitrobenzenesulfonyl chloride (20.0 g, 66.6 mmol) was dissolved in 1,4- dioxane (100 ml) and cooled to 000. Aqueous ammonia (400 ml, 0.50 M, 200 mmol) was slowly added and stirring was continued at room temperature until completion of thereaction. The solvent was removed under reduced pressure and dichloromethane was added. The organic phase was washed with water three times. The suspension was filtered (solid is product), and the organic phase was washed with brine. The combined organic phases were dried over sodium sulfate and the solvent was removed under reduced pressure. The crude was recrystallized from diethyl ether to yield 16.4 g (93%purity, 88 % yield).LC-MS (Method B): Rt = 0.45 mm; MS (ESIpos): mlz = 281 [M+H]

References:

WO2017/191000,2017,A1 Location in patent:Page/Page column 164; 165