Acetyl bromide → 4-Bromo-2,5-dimethylpyridine 1-oxide

Participants

Reaction Conditions

Reaction Steps

To a solution of acetyl bromide (43.09 mL, 582.81 mmol) in acetic acid (70 mL) was added 2,5-dimethyl-4-nitro-1-oxido-pyridin-1-ium (which may be prepared as described in Description 135) (9.8 g, 58.28 mmol) dropwise over 5 mins. After addition, the mixture was stirred at 80° C. overnight. The reaction mixture was poured on to ice and the solution basified to pH 8 with cold 2M sodium hydroxide. The aqueous layer was extracted with DCM (3x). The combined organics were washed with brine, dried over magnesium sulphate, filtered and evaporated to a pale yellow solid, 4-bromo-2,5-dimethyl-1-oxido-pyridin-1-ium (D136) (12.3 g);

Provenance & Evidence