反应详情

温度

50 °C

4-Chloro-2,5-dimethoxypyrimidine (CDMP; 15 g, 0.086 mol) was dissolved in N-methyl-2-pyrrolidinone (NMP; 62.5 g) at ambient temperature. Sodium hydrogen cyanamide (12.1 g, 2.2 eq) was added all at once, and the mixture was heated to 50° C. with stirring for 2.5 h. The resulting slurry was cooled to 25° C., and 150 mL of water was added. Concentrated hydrochloric acid was added drop-wise until a pH of 5.5 was reached. The thick slurry was filtered and washed twice with 10 mL of water to afford 2,5-dimethoxy-4-cyanoamino-pyrimidine (2) as a white solid (11.83 g, 76% yield).

1. temperatureThe resulting slurry was cooled to 25° C.
2. filtrationThe thick slurry was filtered
3. washwashed twice with 10 mL of water