Potassium Iodide → 6-bromo-3-iodo-2-methoxypyridine

Participants

Reaction Steps

A solution of sodium nitrite (5.44 g) in water (15 mL) was added dropwise to a suspension of 6-bromo-2-methoxypyridin-3-amine (16.0 g) in concentrated hydrochloric acid (130 mL) and water (175 mL) at an internal temperature of 5° C. or less, and the mixture was stirred as such for 20 minutes. This suspension was added dropwise to a solution of potassium iodide (39.2 g) in water (760 mL) at an internal temperature of 5° C. or less. The mixture was brought to room temperature and then stirred at 60° C. for two hours. The reaction solution was brought to room temperature and then extracted with ethyl acetate. The organic layer was washed with a saturated sodium thiosulfate solution and brine, dried over anhydrous magnesium sulfate and filtered, after which the filtrate was concentrated under reduced pressure. The resulting residue was purified by silica gel column chromatography (hexane:ethyl acetate=95:5→85:15) to give 6-bromo-3-iodo-2-methoxypyridine as a pale orange powder (21.1 g).

Provenance & Evidence