4-Bromo-N,N,3-trimethylbenzenesulphonamide synthesis

Yield:849532-31-6 94%

Reaction Conditions:

with N-ethyl-N,N-diisopropylamine in tetrahydrofuran at 0 - 20;

Steps:

Diisopropylethylamine (4.95 ml_, 27.8 mmol) was added at 0 °C to a stirred solution of dimethylamine (3.70 ml_, 55.6 mmol) in tetrahydrofuran (25 ml_) and the reaction mixture was stirred at room temperature for 15 minutes. A 0.1 M solution of 4- bromo-3-methyl-benzenesulfonyl chloride (3.0 g, 11 mmol) in tetrahydrofuran was added at room temperature and the reaction mixture was stirred at room temperature for 2 hours. The solvent was evaporated off under reduced pressure. The residue was diluted with ethyl acetate, and the inorganic salts were filtered through a celite bed. The filtrate was washed with 2 N aqueous HCI, dried over anhydrous sodium sulfate, filtered, and concentrated in vacuo to afford 2.90 g (94%) of 4-bromo-3- methyl-Λ/,Λ/-dimethyl-benzenesulfonamide, which was used in subsequent reactions without further purification. MS cald. for C₉H₁₂BrNO₂S [M⁺] 278.2, obsd. 280.0.

References:

WO2010/55005,2010,A1 Location in patent:Page/Page column 84