Trifluoroacetic acid → 4-Cyclopropylethynyl-6-hydroxy-4-trifluoromethyl-1,4-dihydro-benzo [d][1,3]oxazin-2-one

Participants

Reaction Steps

To 150 mg (0.39 mmol) of 8 was added 2 mL of trifluoroacetic acid. The mixture was allowed to stir at room temperature for 2 hours. The reaction mixture was concentrated under reduced pressure, and the residue was purified by preparative thin layer chromatography (2 mm silica gel plate, E. Merck) using 5% methanol in dichloromethane to give 110 mg (0.37 mmol, 96%) of 9 as a colorless oil [LC-MS; M+H 298.1].

Provenance & Evidence