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

Participants

Reaction Conditions

Reaction Steps

A mixture of 5-nitro-3-(trifluoromethyl)pyridin-2-ol (2.65 g), phosphorus pentachloride (3.17 g) and phosphorus oxychloride (1.5 mL) was stirred at 90° C. for 3 hr. After cooling to room temperature, the reaction mixture was poured into ice, and the mixture was extracted with ethyl acetate. The extract was washed with saturated brine, dried over anhydrous magnesium sulfate, and concentrated under reduced pressure. The residue was purified by silica gel column chromatography (eluent: hexane-ethyl acetate=19:1→3:1) to give the title compound as a yellow oil (yield 2.21 g, 77%).

Provenance & Evidence