反应详情

To a stirred solution of 22 g of sodium in 450 ml of anhydrous ethanol was added, portionwise, 43.5 g of 4-chloro-3-hydrazono-2-oxindole, and the resulting solution was heated under reflux for 30 minutes. The cooled solution was then concentrated to a gum, which was dissolved in 400 ml of water and decolorized using activated carbon. The resulting solution was poured onto a mixture of 1 liter of water and 45 ml of concentrated hydrochloric acid. The precipitate which formed was recovered by filtration, dried and recrystallized from ethanol, giving 22.4 g of 4-chloro-2-oxindole, mp 216°-218° C. (dec).

1. temperatureunder reflux for 30 minutes
2. concentrationThe cooled solution was then concentrated to a gum, which
3. dissolutionwas dissolved in 400 ml of water
4. additionThe resulting solution was poured onto a mixture of 1 liter of water and 45 ml of concentrated hydrochloric acid
5. customThe precipitate which formed
6. filtrationwas recovered by filtration
7. customdried
8. customrecrystallized from ethanol