反应详情

温度

150 °C

Add hydroxylamine hydrochloride (608 mg, 8.8 mmol) to a solution of 6-Bromo-2,4-difluoro-3-methoxy-benzaldehyde (2.0 g, 7.96 mmol) in anhydrous DMF (4 ml). Heat the mixture to 150° C. for 2 h. Add water to the cooled mixture and extract the product with EtOAc (×2). Wash the combined organic layers with water (×3), saturated aq. sodium chloride and dry over anhydrous sodium sulfate. Filter and concentrate. Dissolve the concentrate in anhydrous THF and add 3 equivalent of the Burgess reagent ((methoxycarbonylsulfamoyl)triethylammonium hydroxide, inner salt). Heat the mixture under reflux under nitrogen atmosphere overnight. Concentrate to yield a crude residue. Purification by flash chromatography (Silica gel-hexane/EtOAc) yields the title compound.

1. extractionAdd water to the cooled mixture and extract the product with EtOAc (×2)
2. washWash the combined organic layers with water (×3), saturated aq. sodium chloride
3. dry with materialdry over anhydrous sodium sulfate
4. filtrationFilter
5. concentrationconcentrate
6. dissolutionDissolve the
7. concentrationconcentrate in anhydrous THF
8. temperatureHeat the mixture
9. temperatureunder reflux under nitrogen atmosphere overnight
10. concentrationConcentrate
11. customto yield a crude residue
12. customPurification by flash chromatography (Silica gel-hexane/EtOAc)