反应详情

4-Dimethylamino-2-oxo-but-3-enoic acid ethyl ester (195 g, 1.14 mol) and hydrazine dihydrochloride (119.7 g, 1 eq) were dissolved in EtOH (1 L) and stirred at room temperature overnight. The mixture was then heated to reflux for 2 hours. The reaction mixture was allowed to cool to room temperature and filtered. The solid was washed with water three times and dried. The filtrate was concentrated to a thick oil and added dropwise into a flask with stirred EtOAc (200 mL). The resulting solid was filtered and rinsed with a small amount of EtOAc. The filtered solids were combined to give the product (62 g, 39% yield). MS (ES) m/z 141.1 (M+H+).

1. temperatureThe mixture was then heated
2. temperatureto reflux for 2 hours
3. temperatureto cool to room temperature
4. filtrationfiltered
5. washThe solid was washed with water three times
6. customdried
7. concentrationThe filtrate was concentrated to a thick oil
8. additionadded dropwise into a flask with stirred EtOAc (200 mL)
9. filtrationThe resulting solid was filtered
10. washrinsed with a small amount of EtOAc