反应详情

The compound obtained in (2) above (10.9 gm) was added to 6 ml of cold concentrated sulfuric acid, and to the mixture was dropwise added 5.8 gm of potassium nitrate in 15 ml of concentrated sulfuric acid, while maintaining the internal temperature below 5° C. After the addition, the mixture was stirred for a further 20 minutes. The reaction product was poured into ice-cold water and extracted with ethyl acetate. The ethyl acetate layer was dried over anhydrous sodium sulfate and the solvent was evaporated. The residue was subjected to silica gel column chromatography using a hexane-ethyl acetate (90:7) mixed solvent as an eluant to obtain fractions containing the target compound. The fractions were concentrated to produce 7.1 gm of the title compound.

1. temperaturewhile maintaining the internal temperature below 5° C
2. additionAfter the addition
3. additionThe reaction product was poured into ice-cold water
4. extractionextracted with ethyl acetate
5. dry with materialThe ethyl acetate layer was dried over anhydrous sodium sulfate
6. customthe solvent was evaporated
7. additionmixed solvent as an eluant
8. customto obtain fractions
9. additioncontaining the target compound
10. concentrationThe fractions were concentrated