Sulfuric Acid → HCID 11674351, compound

Participants

Reaction Steps

To a solution of ethyl 6-[N-(2,4-difluorophenyl)sulfamoyl]-1-cyclohexene-1-carboxylate (Compound 3, 300 mg) obtained in Example 3 in methanol (6 ml), concentrated sulfuric acid (0.4 ml) was added and the mixture was stirred under reflux for 8 days. The reaction mixture was concentrated under reduced pressure and diluted with ethyl acetate (30 ml) and washed with water (30 ml). The ethyl acetate layer was washed with water (30 ml×2) and dried over anhydrous magnesium sulfate and the solvent was distilled off under reduced pressure. The residue was purified by silica gel chromatography (eluent: ethyl acetate/hexane=1/5→ethyl acetate/hexane=1/2) and then crystallized from diisopropyl ether to yield methyl 6-[N-(2,4-difluorophenyl)sulfamoyl]-1-cyclohexene-1-carboxylate (Compound 22; 95 mg) as colorless powdery crystals.

Provenance & Evidence