[F:1][C:2]1[CH:3]=[CH:4][CH:5]=[C:6]2[C:10]=1[NH:9]C(=O)[C:7]2=[O:12].[OH:13]O.Cl>[OH-].[Na+]>[NH2:9][C:10]1[C:2]([F:1])=[CH:3][CH:4]=[CH:5][C:6]=1[C:7]([OH:12])=[O:13]A solution of 7-fluoro-1H-indol-2,3-dione (13.0 g, 78.7 mmol) in 10N sodium hydroxide (125 mL) was heated and stirred at 70° C. for 1 hour. 30% Hydrogen peroxide (25 mL) was added dropwise over 20 minutes at the same temperature, and the mixture was heated and stirred at the same temperature further for 1 hour. The solution was ice cooled, and conc. hydrochloric acid was added to the solution carefully until the pH of the solution became 4. Organic matter was extracted with ethyl acetate, and the extract was washed with saturated brine and dried over anhydrous magnesium sulfate, and the solvent was evaporated under reduced pressure. The crystals thus obtained were collected by filtration to give the title compound (7.15 g, 59% yield).
Wird geladen…
