反应详情

温度

30 °C

To a solution of N-benzyl-2-nitro-N-(3-oxobutyl)benzenesulfonamide (compound F, 30 g, 83 mmol) in methanol (300 ml) was added bromine (4.69 ml, 91 mmol) in one portion at 20-25° C. Stirred for 20 hours (no bromine colour), water (20 ml) added, heated to reflux for 30 min, diluted with MeOH (100 ml). The solution was cooled to 30° C. with stirring, seeded with compound G, stirred at 25-30° C. for 5 min (crystallisation occurred), cooled to 15° C., aged for 1 hour. Crystals collected, washed with 2×15 ml of MeOH (20-25° C.), dried on air to give N-benzyl-N-(4-bromo-3-oxobutyl)-2-nitrobenzenesulfonamide (19.4 g, 44.0 mmol, 53.1% yield).

1. additionadded
2. temperatureheated
3. temperatureto reflux for 30 min
4. stirringstirred at 25-30° C. for 5 min
5. custom(crystallisation occurred)
6. temperaturecooled to 15° C.
7. customCrystals collected
8. washwashed with 2×15 ml of MeOH (20-25° C.)
9. customdried on air