反应详情

30 ml of concentrated hydrochloric acid and 60 ml of acetic acid were added to 3.74 g of 3-cyano-6-(2-fluorophenoxy)-7-methylsulfonylamino-4H-1-benzopyran-4-one. The mixture was refluxed for 30 minutes. After the completion of the reaction, the solvent was removed by distillation under reduced pressure. The residue was washed with water and then recrystallized from acetic acid to obtain 1.65% (yield: 42.1%) of 3-carbamoyl-6-(2-fluorophenoxy)-7-methylsulfonylamino-4H-1-benzopyran-4-one having a melting point of 249°-251° C.

1. temperatureThe mixture was refluxed for 30 minutes
2. customAfter the completion of the reaction
3. customthe solvent was removed by distillation under reduced pressure
4. washThe residue was washed with water
5. customrecrystallized from acetic acid