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A tetrahydrofuran solution of 3.00 M methylmagnesium chloride (125 mL, 0.38 mol) was added slowly and dropwise to a tetrahydrofuran (500 mL) solution of 4-bromo-3-fluoro-N-methoxy-N-methylbenzamide (58.5 g, 0.223 mol) at 0 °C. The reaction mixture was stirred continuously at 0 °C for 1 hour. Upon completion of the reaction, the reaction was quenched with pre-cooled saturated ammonium chloride solution (150 mL). The organic layer was separated and the remaining aqueous phase was extracted with ethyl acetate (3 x 50 mL). All organic phases were combined, washed with saturated brine, dried with anhydrous magnesium sulfate, filtered and concentrated under reduced pressure to afford the crude product 3-fluoro-4-bromoacetophenone (48.4 g, 99% yield), which could be used in the subsequent reaction without further purification.

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