Methyl iodide → 2-Bromo-3-methoxypyridine

Participants

Reaction Steps

To a stirred mixture of 2-bromo-3-pyridinol (71.0 g) and pulverized KOH (77.8 g) in DMSO (500 mL) at 55°-60° C. and under N2 atmosphere was added dropwise a solution of CH3I (72.4 g) in DMSO (100 mL). After the addition was complete, the reaction was maintained at 55°-60° C. for 1/2 h. The mixture was then poured into ice water (800 g) and the precipitate filtered. The precipitate was triturated with Et2O (3×500 mL) and the combined extracts treated in turn with 1 N NaOH (500 mL), water (500 mL), 1 N HCl (3×250 mL), and sat. NaCl solution (500 mL). The organic phase was dried with anhydrous MgSO4, filtered, and concentrated under reduced pressure to afford 2-bromo-3-methoxypyridine (52.3 g; 68%).

Provenance & Evidence