Hydrochloric Acid → 6-Fluoro-1,3-benzoxazol-2(3H)-one

Participants

Reaction Conditions

Reaction Steps

2-amino-5-fluorophenol [4.0 grams (g) (0.03 moles) (M)] was dissolved in 40.0 ml pyridine. The mixture was cooled with an ice bath while triphosgene [3.5 g (0.03 M)] was added. The mixture was heated to 60° C. for 3.0 hours. Thin layer chromatography showed that some of the starting phenol was still present. The mixture was then cooled; triphosgene [0.35 g 0.003 M)] was added and heated to reflux for 4.0 hours. The mixture was cooled, methylene chloride and 10% hydrogen chloride solution was added and stirred to room temperature.

Provenance & Evidence