反应详情

温度

60 °C

2-(Dimethylamino-methyleneamino)-malonic acid diethyl ester (1 g, 4.34 mmol) was dissolved in ethanol (6.5 ml) and the mixture was heated to 60° C. Hydrazine (1M solution in THF, 5.5 ml, 5.52 mmol) was added dropwise during a period of 30 min and the mixture was heated to reflux for another 30 min. The reaction mixture was then cooled to 0° C. for 1 h and the precipitate that formed was filtered off. The filtrate was evaporated and ethyl acetate/methanol 4:1 (16 ml) was added to the oily residue. The suspension that formed was again filtered and the filtrate was evaporated. The remaining residue was triturated with ethyl acetate (9 ml) and the light brown solid was filtered off. The filtrate was again evaporated, the remaining solid triturated with a small amount of ethyl acetate and the resulting light brown solid was filtered off and combined with the first batch to give the title compound (333 mg, 1.95 mmol, 45%). MS: m/e=172.1 [M+H+].

1. temperaturethe mixture was heated
2. temperatureto reflux for another 30 min
3. temperatureThe reaction mixture was then cooled to 0° C. for 1 h
4. customthe precipitate that formed
5. filtrationwas filtered off
6. customThe filtrate was evaporated
7. additionethyl acetate/methanol 4:1 (16 ml) was added to the oily residue
8. customThe suspension that formed
9. filtrationwas again filtered
10. customthe filtrate was evaporated
11. customThe remaining residue was triturated with ethyl acetate (9 ml)
12. filtrationthe light brown solid was filtered off
13. customThe filtrate was again evaporated
14. customthe remaining solid triturated with a small amount of ethyl acetate
15. filtrationthe resulting light brown solid was filtered off