Sulfuric Acid → 5,7-Di-tert-butyl-1H-indole-2,3-dione

Participants

Reaction Conditions

Reaction Steps

N-(2,4-Di-tert-butyl-phenyl)-2-[(E)-hydroxyimino]-acetamide (500 mg, 1.7 mmol) in concentrated sulfuric acid (3.8 mL) was heated at 90° C. for 2 h. This solution was cooled at 0° C. and slowly added to ice-water (15 mL), the brown precipitate was filtered off and purified by chromatography on silica gel with a gradient of 0% to 25% of ethyl acetate in heptane to afford 200 mg (42%) of an orange powder, MS: m/z=259 (M).

Provenance & Evidence