反应详情

温度

60 °C

A solution of the 49.0 grams (0.20 mole) of ethyl 2-(5-fluoro-2-nitrophenoxy)acetate in 100 ml of glacial acetic acid was added to a warm (60° C.), stirred mixture of iron powder (50.0 grams, 0.90 mole) in 300 ml of glacial acetic acid. The reaction temperature was allowed to reach 100° C., and the mixture was stirred for approximately three hours. This mixture was poured into water, forming a precipitate. The precipitate was collected by filtration and was recrystallized from ethanol to yield 25.0 grams of 7-fluoro-2H-1,4-benzoxazin-3(4H)-one; another sample of this compound prepared in a similar manner, and then purified further, had a melting point of 205°-206° C. and an nmr spectrum which was consistent with the proposed structure.

1. customto reach 100° C.
2. stirringthe mixture was stirred for approximately three hours
3. customforming a precipitate
4. filtrationThe precipitate was collected by filtration
5. customwas recrystallized from ethanol