Methyl iodide → 2-Fluoro-4-iodo-3-methylpyridine

Participants

Reaction Steps

n-Butyl lithium (1.6M hexane solution, 53.8 mL) was added to a solution of diisopropylamine (8.71 g) in THF (200 mL) at −10 C. After being stirred at the same temperature under nitrogen atmosphere for 1 hour, a solution of 2-fluoro-3-iodopyridine (18.3 g) in THF (70 mL) was added to the reaction mixture at −78 C. The mixture was stirred at the same temperature under nitrogen atmosphere for 1 hour. A solution of iodomethane (12.8 g) in THF (30 mL) was added to the reaction mixture at −78 C. The mixture was stirred at the same temperature under nitrogen atmosphere for 2 hours. The mixture was quenched with aqueous saturated ammonium chloride solution at 0 C and extracted with ethyl acetate. The organic layer was separated, washed with water and brine, dried over anhydrous magnesium sulfate and concentrated in vacuo. The residue was passed through NH-silica and concentrated in vacuo. The residue was purified by a silica gel column chromatography (hexane/ethyl acetate) to give the title compound (17.2 g).

Provenance & Evidence