反应详情

In 2 ml of ethanol was dissolved 0.5 g of ethyl trans-4-(3,4-dihydro-2,2-dimethyl-6-nitro-2H-1,4-benzoxazin-4yl)-4-oxo-2-butenoate followed by addition of 1.5ml of an aqueous solution of 0.06 g of sodium hydroxide. The mixture was stirred at room temperature for 2 hours. The ethanol was distilled off under reduced pressure and the residue was adjusted to pH 4 with 1N hydrochloric acid. The resulting precipitate was recovered by filtration and washed with water and ethanol to give 0.31 g of trans-4-(3,4-dihydro-2,2-dimethyl-6-nitro-2H-1,4-benzoxazin-4-yl)-4-oxo-2-butenoic acid.

1. distillationThe ethanol was distilled off under reduced pressure
2. filtrationThe resulting precipitate was recovered by filtration
3. washwashed with water and ethanol