Sulfuric Acid → 2,3-Dichloro-5-iodo-6-methoxypyridine

Participants

Reaction Steps

A RBF was charged with 2,3-dichloro-6-methoxypyridine (4.84 g, 27.2 mmol, Accel Pharmtech), DCM (40.0 ml), AcOH (40.0 ml), and sulfuric acid (0.797 ml, 14.95 mmol) to give a clear solution. N-iodosuccinimide (6.12 g, 27.2 mmol) was added in one portion to give a maroon-colored solution. The reaction was stirred for three hours at RT. The mixture was diluted with ethyl acetate, washed with water, washed with 10% aq. sodium thiosulfate, washed with brine, dried over sodium sulfate, filtered, and concentrated. The residue was purified by chromatography on silica gel (80-g Redi-Sep Gold column, 0-15% Et20/Heptane) to afford 2,3-dichloro-5-iodo-6-methoxypyridine (6.29 g, 20.70 mmol, 76% yield) as a white solid. m/z (ESI) 304.0 (M+H)+.

Provenance & Evidence