Triethylamine → 5-bromo-2-fluoro-N-methoxy-N-methylbenzamide

Participants

Reaction Steps

To a suspension of 5-bromo-2-fluorobenzoic acid (29 g, 132 mmol) in anhydrous DCM (500 mL) was added oxalyl chloride (16.8 mL, 199 mmol) and 5 drops of DMF. The suspension was stirred at room temperature for 2 hours. The solvent and excess oxalyl chloride were removed by rotary evaporation, and the residue was dissolved in anhydrous DCM (500 mL). With vigorous stirring, N,O-dimethylhydroxylamine hydrochloride (16.8 g, 172.3 mmol) was added in one portion, followed by triethylamine (80 mL, 574 mmol). The thick suspension was stirred for 1 hour at room temperature and then filtered. The organic layer was washed sequentially with 1M HCl, 1M NaOH, and water, dried over Na2SO4, and concentrated to afford the product. 1H NMR (400 MHz, CDCl3) δ 7.55 (dd, J=5.7, 2.5 Hz, 1H), 7.50 (ddd, J=8.7, 4.6, 2.5 Hz, 1H), 7.00 (t, J=8.8 Hz, 1H), 3.56 (s, 3H), 3.34 (s, 3H).

Provenance & Evidence