Uses
4-Bromo-2-methoxypyridine used in the synhesis of Imidazo [1, 2-a] pyrimidines. Suzuki coupling between 4-methoxyphenylboronic acid and 4-bromo-2-methoxypyridine affords 1, 5-disubstituted pyridones. Starting material used in a synthesis of crown-ester-bipyridines and viologens via sodium or nickel reductive coupling, side chain oxidation and esterification.
Synthesis
A non-homogeneous reaction mixture formed by 4-bromo-2-fluoropyridine (2.64 mL, 25.6 mmol) and sodium methanolate (8.29 g, 153 mmol) in methanol (36.5 mL) was placed in a pressure tube and reacted for 5 hours at 155°C. Upon completion of the reaction, the mixture was cooled to room temperature, filtered to remove the solid insoluble material and the solids were washed with ethyl acetate. The filtrate was concentrated to give a light yellow oil containing a small amount of white solid. The yellow oily material was decanted, diluted with water and the aqueous phase was extracted with ethyl acetate (2×). The organic layers were combined, washed sequentially with water and saturated saline, dried over anhydrous magnesium sulfate, filtered and concentrated to afford the target product 4-bromo-2-methoxypyridine (4.43 g, 21.20 mmol, 83% yield) as a yellow oil.LC-MS analysis: the calculated value of C6H6BrNO was 188.02, and the measured values of [M + H]+ were 187.9, 189.9. 1H NMR was used as the analyte. 189.9. 1H NMR (400 MHz, CDCl3) δ 7.98 (d, J = 5.5 Hz, 1H), 7.02 (dd, J = 5.5, 1.5 Hz, 1H), 6.94 (d, J = 1.8 Hz, 1H), 3.92 (s, 3H).
