Under nitrogen protection, 2-cyano-3-methoxypyridine (0.88 g, 6.5 mmol) was dissolved in a three-necked flask containing 20 mL of anhydrous tetrahydrofuran. The reaction system was cooled to 0 °C, followed by slow dropwise addition of tetrahydrofuran solution of methylmagnesium iodide (3 M, 4.3 mL, 12.8 mmol). The reaction temperature was maintained at 0 °C with continuous stirring for 2 hours. Upon completion of the reaction, the reaction was quenched by the slow addition of 50 mL of water at 0 °C. The pH of the reaction solution was adjusted to 7 with 2 N hydrochloric acid and subsequently extracted with ethyl acetate (3 x 50 mL). The organic phases were combined, dried with anhydrous sodium sulfate and concentrated under reduced pressure to give the crude product. Purification by silica gel column chromatography (eluent: hexane/ethyl acetate, gradient 0-100%) afforded the target compound 1-(3-methoxypyridin-2-yl)ethanone as a colorless oil (0.79 g, yield 79%). The product was confirmed by 1H-NMR (CDCl3): δ 8.42 (dd, J = 7.7, 1.4 Hz, 1H), 7.63 (dd, J = 7.6, 1.4 Hz, 1H), 7.61 (dd, J = 7.7, 7.6 Hz, 1H), 3.82 (s, 3H), 2.14 (s, 3H). Mass spectrum (ESI+): m/z 152 ([M+H]+).
