N-bromobutanimide → 6-Bromo-3H-oxazolo(4,5-b)pyridin-2-one

Participants

Reaction Steps

To a solution of 3H-oxazolo[4,5-b]pyridin-2-one (13.6 g, 100 mmol) in acetonitrile (600 mL) and acetic acid (120 mL) was added N-bromosuccinimide (21.4 g, 120 mmol). The mixture was stirred at room temperature for 4 hr and the reaction was quenched with Na2S2O5 solution. After evaporation, the residue was partitioned between ethyl acetate and water. The organic layer was washed with 2N NaOH solution, brine, and dried over Na2SO4. The crude product was purified on a silica gel column to provide 6-bromo-3H-oxazolo[4,5-b]pyridin-2-one (11.5 g, 55% yield).

Provenance & Evidence