反应详情

温度

85 °C

After a suspension of 10.0 g of 4-furan-2-yl-2,4-dioxo-butyric ethyl ester prepared above and hydroxylamine hydrochloride was stirred at 85° C. for 2 hrs, the solvent was removed under reduced pressure. The concentrate was dissolved in a mixture of methylene chloride and distilled water, followed by separating the organic layer. The organic layer was dried over anhydrous sodium sulfate, filtered through a silica gel layer, and concentrated in vacuo to produce a yield of 8.01 g of 5-furan-2-yl-isoxazole-3-carboxylic acid ethyl ester (Yield 77%). The concentrate was used in the next step without further purification.

1. customthe solvent was removed under reduced pressure
2. dissolutionThe concentrate was dissolved in a mixture of methylene chloride
3. distillationdistilled water
4. customby separating the organic layer
5. dry with materialThe organic layer was dried over anhydrous sodium sulfate
6. filtrationfiltered through a silica gel layer
7. concentrationconcentrated in vacuo