Phosphorus oxychloride → 2-Chloro-3-nitro-5-(trifluoromethyl)pyridine

Participants

Reaction Conditions

Reaction Steps

2-Hydroxy-3-nitro-5-trifluoromethylpyridine (8.8 g, 42.3 mmol) was added to a mixture of phosphorous oxychloride (4.2 mL, 45.9 mmol) and phosphorous pentachloride (9.6 g, 46.1 mmol) at 60° C. The reaction mixture was then heated under nitrogen at 80° C. overnight. The resulting dark product mixture was allowed to cool to room temperature and was poured into ice/water. The mixture was extracted with ether and the ether extract was washed with water and brine. After drying over magnesium sulfate, the solvent was removed to leave a dark oil which was subjected to flash chromatography on silica gel eluting with chloroform. Fractions containing only the desired product were combined and concentrated to leave a brown oil (5.0 g, 52%). 1H NMR (DMSO-d6): δ9.20 (s, 1H), 9.07 (s, 1H).

Provenance & Evidence