反应详情

To a stirred slurry of 43.3 g of 4-chloroisatin in 350 ml of ethanol was added 17.3 ml of hydrazine hydrate, and then the reaction mixture was cooled, and the precipitate was recovered by filtration to give 43.5 g of 4-chloro-3-hydrazono-2-oxindole, m.p. 235°-236° C.

1. temperaturethe reaction mixture was cooled
2. filtrationthe precipitate was recovered by filtration