Potassium Carbonate → 4-Bromo-3-fluoro-N-methoxy-N-methylbenzamide

Participants

Reaction Steps

Oxalyl chloride (38.1 mL, 0.450 mol) was slowly added to a mixture of 4-bromo-3-fluorobenzoic acid (49.3 g, 0.225 mol) in methylene chloride (300 mL), then DMF (1.0 mL) was added and the reaction was stirred at RT for 2 h. The volatiles were removed under reduced pressure and co-evaporated with toluene for 3 times. The residue was then dissolved in methylene chloride (100 mL). The solution was added dropwise to a mixture of N,O-dimethyl-hydroxylamine hydrochloride (30.7 g, 0.315 mol) and potassium carbonate (120 g, 0.90 mol) in methylene chloride (300 mL) and water (300 mL). The reaction was stirred at RT for 2 h. The organic layer was separated. The aqueous layer was extracted with methylene chloride (2×50 mL). The combined organic layers were washed with brine, dried over MgSO4, filtered, and concentrated under reduced pressure to give the product (58.5 g, 99%). Analytical LCMS: (M+H)+=261.9/263.9.

Provenance & Evidence