Dimethylformamide → 2-bromo-5-fluorobenzamide

Participants

Reaction Steps

A solution of 2-bromo-5-fluorobenzoic acid (10.0 g, 45.66 mmol) in dichloromethane (100 ml) was treated at 25° C. with oxalyl chloride (8.0 ml, 91.3 mmol) followed by a drop of N,N-dimethylformamide. The resulting mixture was then stirred for 4 h. The solvent and excess reagent were evaporated in vacuo and the residual oil was dissolved in tetrahydrofuran (100 ml) and added to a mixture of tetrahydrofuran (200 ml), water (100 ml) and concentrated ammonium hydroxide (10 ml). The resulting mixture was then stirred at 25° C. for 20 h. The reaction mixture was diluted with ethyl acetate, washed with brine, dried over anhydrous magnesium sulfate and concentrated to give 9.51 g (96% yield) of the title amide as a white solid. 1HNMR 400 MHz (CDCl3) δ (ppm): 5.9-6.3 (2H, broad, NH2), 7.05 (1H, m, aromatic), 7.42 (1H, dd, J=3.2 Hz and J=8.3 Hz, aromatic), 7.61 (1H, dd, J=5.1 Hz and J=9.1 Hz, aromatic).

Provenance & Evidence