反应详情

In 70 ml of pyridine were dissolved 18.3 g (70 mmol) of ethyl 5-fluoro-6-acetoxy-1,2,3,4,5,6-hexahydro-2,4-dioxopyrimidine-5-carboxylate and 13.1 g (105 mmol) of (E)-5-methylfurfuraldoxime (containing 13% of the Z form), and 7.07 g (70 mmol) of triethylamine was added to the solution, followed by stirring at room temperature for 15 hours. The reaction solution was poured into 500 ml of ice-cooled water, and crystals precipitated were collected by filtration and washed with water. The crystals were dried under reduced pressure (P2O5) and recrystallized from 170 ml of ethanol to give 11.8 g of ethyl 5-fluoro-6-[(E)-5-methylfurfurylideneaminooxy]-1,2,3,4,5,6-hexahydro-2,4-dioxopyrimidine-5-carboxylate. m.p. 181°-182° C.

1. additionwas added to the solution
2. customprecipitated
3. filtrationwere collected by filtration
4. washwashed with water
5. dry with materialThe crystals were dried under reduced pressure (P2O5)
6. customrecrystallized from 170 ml of ethanol