124-63-0

591-19-5

83922-51-4

Step i: To a stirred solution of anhydrous dichloromethane (200 ml) of m-bromoaniline (6 g, 34.87 mmol) was sequentially added pyridine (4.13 mg, 52.31 mmol) and methanesulfonyl chloride (5.194 g, 45.34 mmol) at 10 °C. The reaction mixture was stirred at room temperature for 15 h. The progress of the reaction was monitored by thin layer chromatography (TLC, the unfolding agent was a hexane solution of 35% ethyl acetate). After completion of the reaction, the reaction mixture was diluted with dichloromethane (50 ml) and washed with 1N hydrochloric acid (25 ml). The organic layer was dried with anhydrous sodium sulfate and concentrated under reduced pressure to give N-(3-bromophenyl)methane sulfonamide 8.45 g in 96.3% yield. The product was structurally confirmed by 1H NMR (DMSO-d6, 300 MHz) and mass spectrometry (MS: m/z = 251.8 [M + 1]).