Pyridinium hydrobromide → 4-bromo-5-methoxypyridin-2(1H)-one

Participants

Reaction Conditions

Reaction Steps

2.82 g (176 mmol, 20 eq.) of pyridinium hydrobromide were added to a solution of 1.94 g (8.81 mmol) of 4-bromo-2,5-dimethoxypyridine in 80 ml of dimethylformamide, the mixture was stirred at 100° C. for 3 h and concentrated under reduced pressure. The residue was triturated with 50 ml of water, filtered off, washed with water and dried under reduced pressure. The filtrate was extracted twice with dichloromethane/methanol (10:1). The combined organic phases were dried (sodium sulphate), filtered, concentrated under reduced pressure and dried. Yield: 771 mg (43% of theory) and 465 mg (purity 88%, 23% of theory)

Provenance & Evidence