反应详情

温度

0 °C

2-Oxindole (6.5 g) was dissolved in 25 mL concentrated sulfuric acid and the mixture maintained at −10 to −15° C. while 2.1 mL of fuming nitric acid was added dropwise. After the addition of the nitric acid the reaction mixture was stirred at 0° C. for 0.5 hr and poured into ice-water. The precipitate was collected by filtration, washed with water and crystallized from 50% acetic acid. The crystalline product was then filtered, washed with water and dried under vacuum to give 6.3 g (70%) of 5-nitro-2-oxindole.

1. additionwas added dropwise
2. filtrationThe precipitate was collected by filtration
3. washwashed with water
4. customcrystallized from 50% acetic acid
5. filtrationThe crystalline product was then filtered
6. washwashed with water
7. customdried under vacuum