反应详情

温度

10 °C

300 ml of toluene was added to a 600 ml water solution of 37.5 g of sodium hydroxide. Then 150 g of dicyclohexylamine salt of 6-fluoro-3-hydroxy-2-pyrazinecarbonitrile was added at 15 to 25° C. and the solution was stirred at the same temperature for 30 minutes. The water layer was separated and washed with toluene, and then 150 ml of water was added, followed by dropwise addition of 106 g of a 30% hydrogen peroxide solution at 15 to 30° C. and one-hour stirring at 20 to 30° C. Then 39 ml of hydrochloric acid was added, the seed crystals were added at 40 to 50° C., and 39 ml of hydrochloric acid was further added dropwise at the same temperature. The solution was cooled to 10° C. the precipitate was filtered and collected to give 65.6 g of 6-fluoro-3-hydroxy-2-pyrazinecarboxamide as a slightly yellowish white solid.

1. customThe water layer was separated
2. washwashed with toluene
3. addition150 ml of water was added
4. additionfollowed by dropwise addition of 106 g of a 30% hydrogen peroxide solution at 15 to 30° C. and one-hour
5. stirringstirring at 20 to 30° C
6. additionThen 39 ml of hydrochloric acid was added
7. additionthe seed crystals were added at 40 to 50° C.
8. addition39 ml of hydrochloric acid was further added dropwise at the same temperature
9. filtrationwas filtered
10. customcollected