The following reagents were added sequentially to the microwave reaction tube: 469.80 μL (4.07 mmol) of 3-bromo-5-methylpyridine dissolved in 20 mL of H2O/DMF (1:3, v/v), 2.03 mL (5.70 mmol) of tributyl(1-ethoxyethenyl)tin, 57.12 mg (81.38 μmol) of chlorinated bis(triphenylphosphine)co-palladium (II), 1.12 g (8.14 mmol) potassium carbonate. The reaction mixture was concentrated to dryness under reduced pressure after microwave radiation at 110 °C for 1 hour. The residue was dissolved in water and extracted with ethyl acetate. The organic phase was dried with anhydrous magnesium sulfate, filtered and concentrated to dryness under reduced pressure. The residue was dissolved in a mixture of 6 mL of methanol and 1 mL of 1N hydrochloric acid and stirred overnight at room temperature. The reaction mixture was concentrated to dryness under reduced pressure and the residue was dissolved in saturated aqueous sodium bicarbonate solution and extracted with ethyl acetate. The organic phase was dried with anhydrous magnesium sulfate, filtered and concentrated to dryness under reduced pressure. The crude product was purified by silica gel column chromatography (eluent: 50/50 ethyl acetate/heptane) to give 160 mg of 1-(5-methylpyridin-3-yl)ethanone. The product characterization data were as follows: LC/MS (Method G): ESI+ [M+H]+: m/z 136, retention time (tr) = 0.38 min. 1H NMR (300 MHz, DMSO-d6, δ, ppm): 2.58 (s, 3H), 2.61 (s, 3H), 7.38 (m, 1H), 8.20 (m, 1H). 8.57 (m, 1H).
