反应详情

To a cooled (0° C.) solution of 5-bromo-2-(methyloxy)-3-pyridinamine (20.3 g, 100 mmol) in pyridine (200 mL) was added slowly 2,4-difluorobenzenesulfonyl chloride (21.3 g, 100 mmol) over 15 min (reaction became heterogeneous). The ice bath was removed and the reaction was stirred at ambient temperature for 16 h, at which time the reaction was diluted with water (500 mL) and the solids filtered off and washed with copious amounts of water. The precipitate was dried in a vacuum oven at 50° C. to give N-[5-bromo-2-(methyloxy)-3-pyridinyl]-2,4-difluorobenzenesulfonamide (12 g, 31.6 mmol, 31.7% yield) MS (ES)+ m/e 379.0, 380.9 [M+H]+.

1. custom(reaction became heterogeneous)
2. customThe ice bath was removed
3. additionwas diluted with water (500 mL)
4. filtrationthe solids filtered off
5. washwashed with copious amounts of water
6. customThe precipitate was dried in a vacuum oven at 50° C.