Step B: 2-methyl-5-nitrobenzenesulfonyl chloride (10.0 g, 43.7 mmol) was dissolved in ether (300 mL) under nitrogen protection and cooled to 0 °C. Ammonia (40 mL) was added slowly and the reaction mixture was stirred at 0 °C for about 42 hours. After the reaction was complete, the mixture was filtered and diluted with dichloromethane (600 mL). The organic layer was separated and dried with anhydrous magnesium sulfate. The organic layer was concentrated under reduced pressure to give 2-methyl-5-nitrobenzenesulfonamide (9.2 g, 100% yield).1H NMR (DMSO-d6) δ: 8.60 (d, J = 2.4Hz, 1H), 8.34 (dd, J = 8.0,2.4Hz, 1H), 7.77 (br s, 2H), 7.70 (d, J = 8.4Hz, 1H), 7.70 (d, J = 8.4Hz, 1H). 2.71 (s, 3H).
