2-Bromo-5-fluoro-N-methoxy-N-methylbenzamide → 1-(2-Bromo-5-fluorophenyl)ethan-1-one

Participants

Reaction Conditions

Reaction Steps

2-Bromo-5-fluoro-N-methoxy-N-methylbenzamide (4.0 g, 0.015 mol) was dissolved in THF (30 mL) and the solution was cooled to 0° C. under N2blanket. Methyl magnesium bromide (15.26 mL, 0.046 mol) was added dropwise over 30 min. The solution was warmed to room temperature and stirred for 1 hour. The solution was cooled to 0° C. and quenched with HCl/EtOH (9 mL, 4 M solution). The reaction mixture was transferred to a separatory funnel, diluted with H2O (30 mL), and extracted with Ethyl Acetate (2×40 mL). The combined organic extracts were washed with H2O, brine, and dried over Na2SO4. The solution was concentrated to afford 1-(2-bromo-5-fluorophenyl)ethanone as a yellow oil in 93% yield. This material was used in the subsequent step without further purification. 1H NMR (CDCl3, 500 MHz) δ2.61 (s, 3H), 7.00-7.04 (m, 1H) 7.15-7.18 (m, 1H), 7.53-7.59 (m, 1H).

Provenance & Evidence