反应详情

温度

5 °C

A mixture of N-(4-acetyl-3-hydroxyphenyl)acetamide (9.66 g, 50 mmol) and acetic anhydride (14.2 ml, 15.3 g, 150 mmol) in dichloromethane (150 ml) was cooled to 5° C. and nitric acid (90%, d 1.49, 4.70 ml, 7.00 g, 100 mmol) was added dropwise. The mixture was stirred at room temperature for 1 hour, poured into water (150 ml) and extracted with dichloromethane (3×150 ml). The combined organic fractions were dried (Na2SO4) and evaporated under reduced pressure and the residue was purified by repeated flash column chromatography on silica gel, eluting with hexane/30% ethyl acetate then hexane/50% ethyl acetate. The first isomer to elute was N-(4-acetyl-5-hydroxy-2-nitrophenyl)acetamide as a yellow solid (3.87 g, 33%).

1. extractionextracted with dichloromethane (3×150 ml)
2. dry with materialThe combined organic fractions were dried (Na2SO4)
3. customevaporated under reduced pressure
4. customthe residue was purified by repeated flash column chromatography on silica gel
5. washeluting with hexane/30% ethyl acetate
6. washThe first isomer to elute