反应详情

Pivaloyl chloride (2,2-dimethylpropionyl chloride) (3.6 g) was added cautiously to a suspension of 3,5-diamino-4-cyano-1-methylpyrazole (4.1 g) in pyridine (25 ml). The temperature of the mixture rose to about 60°. The mixture was left to cool overnight and was then poured into a mixture of ice (60 g) and concentrated HCl (40 ml). The precipitate was filtered off, washed and dried, to give 3.9 g of crude 5-amino-4-cyano-3-(2,2-dimethylpropanoylamino)-1-methylpyrazole. Recrystallisation from a 70:30 ethanol/water mixture gave 3.1 g of pure product, mp 245°-247° C.

1. customrose to about 60°
2. waitThe mixture was left
3. temperatureto cool overnight
4. filtrationThe precipitate was filtered off
5. washwashed
6. customdried