反应详情

Nitric acid (10 mL) was slowly added to sulfuric acid (10 mL) at 0° C., and the mixture was stirred at the same temperature for 10 min. To this solution was slowly added 1-benzothiophene 1,1-dioxide (3.99 g) at 0° C., and the mixture was further stirred at the same temperature for 30 min. The reaction mixture was poured into ice water, and the mixture was extracted with ethyl acetate. The extract was washed twice with water, saturated aqueous sodium hydrogencarbonate solution and saturated brine, dried over anhydrous magnesium sulfate, and concentrated under reduced pressure. The residue was recrystallized from ethyl acetate-hexane to give the title compound as a pale-yellow solid (yield 4.26 g, 84%).

1. customat 0° C.
2. stirringthe mixture was further stirred at the same temperature for 30 min
3. extractionthe mixture was extracted with ethyl acetate
4. washThe extract was washed twice with water, saturated aqueous sodium hydrogencarbonate solution and saturated brine
5. dry with materialdried over anhydrous magnesium sulfate
6. concentrationconcentrated under reduced pressure
7. customThe residue was recrystallized from ethyl acetate-hexane