(NE)-N-[(5-methylfuran-2-yl)methylidene]hydroxylamine

Conditions: temp:0.00; pressure:0.00; stir:; See reaction.notes.procedure_details.

Procedure: 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. was added to the solution precipitated were collected by filtration washed with water The crystals were dried under reduced pressure (P2O5) recrystallized from 170 ml of ethanol

Conditions: temp:0.00; pressure:0.00; stir:; See reaction.notes.procedure_details.

Procedure: 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. was added to the solution precipitated were collected by filtration washed with water The crystals were dried under reduced pressure (P2O5) recrystallized from 170 ml of ethanol