Methylmagnesium bromide (MeMgBr, 10 mL, 30.0 mmol) was added slowly and dropwise to a solution of 5-bromo-N,2-dimethoxy-N-methylnicotinamide (5.0 g, 18.18 mmol) in tetrahydrofuran (THF, 50 mL) at -78 °C. The reaction mixture was stirred at 20 °C overnight. Subsequently, the reaction mixture was quenched by pouring into aqueous ammonium chloride (NH4Cl) solution. The mixture was extracted with ethyl acetate (EtOAc). The organic phases were combined, washed with saturated brine, dried over anhydrous sodium sulfate (Na2SO4), filtered and concentrated under reduced pressure. The crude product was purified by column chromatography (eluent: petroleum ether/ethyl acetate=10:1) to afford 1-(5-bromo-2-methoxypyridin-3-yl)ethanone (3.0 g, 71% yield).1H NMR (CDCl3, 400 MHz) δ 8.33 (d, J=2.4Hz, 1H), 8.19 (d, J=2.4Hz, 1H), 4.03 ( s, 3H), 2.63 (s, 3H). Mass spectrum (MS) (M+H)+: 230/232.
