Acetone → 6-(2-Chlorophenylamino)-7-fluoro-3-methyl-benzo[c]-isoxazole-5-carboxylic acid methyl ester

Participants

Reaction Steps

Sodium azide (128 mg, 1.95 mmol) was added to a mixture of 5-acetyl-2-(2-chlorophenylamino)-3,4-difluorobenzoic acid methyl ester (6) (601 mg, 1.59 mmol) in 3:1 acetone:water (16 ml) and heated to reflux. After 16 hours, the reaction mixture was cooled to room temperature, and diluted with EtOAc and water. The organic layer was washed with water, dried (MgSO4) and concentrated. The resulting residue was diluted with water (8 mL) and heated to reflux. After 5 hours, the mixture was cooled to room temperature and diluted with EtOAc. The organic layer was washed with water, dried (MgSO4) and concentrated. Purification by flash column chromatography using the Biotage system (20% EtOAc in hexanes) provided the desired product (55) (410 mg, 77%).

Provenance & Evidence