1310949-37-1

68-12-2

58819-88-8

(1) Dissolve 6-bromo-3-iodo-2-methoxypyridine (1.0 g) in ether (38 mL) under nitrogen protection and cool to -80 °C. N-butyllithium (2.6 M, 0.735 mL) was slowly added and after the drop was completed, stirred at room temperature for 1 hour. Subsequently, N,N-dimethylformamide (0.62 mL) was added slowly dropwise and stirring was continued at -80 °C for 1 hour. Upon completion of the reaction, water was added to the system to quench the reaction and the organic layer was washed with dilute hydrochloric acid. The organic layer was dried over anhydrous magnesium sulfate, filtered and concentrated under reduced pressure. The residue was purified by silica gel column chromatography (eluent: hexane/ethyl acetate = 94:6, gradient to 9:1) to afford 6-bromo-2-methoxypyridine-3-carbaldehyde as a colorless powder (618 mg, 90% yield).