反应详情

121 g (0.5 mol) of 2-nitrophenyl-guanidine-carbonate, 100 g of ethyl acetoacetate and 200 ml of diethylene glycol dimethyl ether are heated first to 65° and, when the evolution of CO2 has ceased, to 140°. In the course of this ethanol and water are distilled off. After 31/2 hours the suspension is cooled, water is added and the pH is adjusted to 4-5 with concentrated hydrochloric acid. The yellow precipitate is filtered off, washed with water and dried in vacuo at 80° C. 80.3 g (65.2% of the theoretical amount) of the title compound of formula ##STR17## (compound No. 2.071) are obtained in the form of crystals having a melting point of 240°-242°.

1. customhas ceased, to 140°
2. distillationIn the course of this ethanol and water are distilled off
3. temperatureAfter 31/2 hours the suspension is cooled
4. additionwater is added
5. filtrationThe yellow precipitate is filtered off
6. washwashed with water
7. customdried in vacuo at 80° C
8. custom2.071) are obtained in the form of crystals