反应详情

温度

0 °C

Under cooling, a solution of 200 mg. of hydroxylamine in 15 ml. of ethanol is combined with 10 ml. of a sodium ethylate solution containing 1% sodium, as well as, in incremental portions, with 1.0 g. of the ethyl ester of 7-chloro-8-methylcarbazole-1-carboxylic acid. The mixture is stirred for one hour at 0° C. and for another 12 hours at room temperature and is then concentrated under vacuum. The residue is taken up in water, acidified to pH 1 with hydrochloric acid, extracted with ethyl acetate, and the extract is washed and concentrated. The residue is recrystallized from ethanol - water, thus obtaining in a 20% yield, 7-chloro-8-methylcarbazole-1-carbohydroxamic acid, m.p. 200° C.

1. temperatureUnder cooling
2. concentrationis then concentrated under vacuum
3. extractionextracted with ethyl acetate
4. washthe extract is washed
5. concentrationconcentrated
6. customThe residue is recrystallized from ethanol - water