Sulfuric Acid → 4,6-dimethyl-1H-indole-2,3-dione

Participants

Reaction Conditions

Reaction Steps

N-(3,5-Dimethyl-phenyl)-2-hydroxyimino-acetamide (13.7 g, 71.3 mmol) was added to concentrated sulfuric acid (70 mL) in a 250 mL flask. The reaction mixture was then heated at 80° C. for 30 minutes, then cooled to room temperature, and poured into ice-water (200 mL). The precipitated solid was filtered and washed with water (100 mL) and dried under vacuum to give 4,6-dimethyl-1H-indole-2,3-dione as an orange solid. Yield: 5.53 g (44%).

Provenance & Evidence