Thionyl Chloride → 2-Chloro-3-nitro-5-(trifluoromethyl)pyridine

Participants

Reaction Steps

A mixture of 2-hydroxy-3-nitro-5-(trifluoromethyl)pyridine (5.0 g), thionyl chloride(28 mL) and N,N-dimethylformamide (3 mL) was heated under reflux for 5 hours. The reaction mixture was concentrated in vacuo, and ice was added to the residue. The mixture was extracted with a mixture of ethyl acetate and tetrahydrofuran. The separated organic layer was washed with brine, dried over.magnesium sulfate, and evaporated in vacuo. The residue was subjected to a silica gel column chromatography eluting with a mixture of n-hexane and ethyl acetate (5:1) and then to an aluminum oxide (activated, basic) column chromatography eluting with ethyl acetate to give 2-chloro-3-nitro-5-(trifluoromethyl)pyridine (4.89 g) as a yellow oil.

Provenance & Evidence