[Synthesis]
To an oven-dried resealable Schlenk tube, ethyl 5,6-dibromonicotinate (1.09 g, 3.5 mmol), methylboronic acid (0.24 g, 4.0 mmol), potassium carbonate (1.46 g, 10.6 mmol), and 1,4-dioxane (27 mL) were added sequentially. Three evacuation-argon backfill cycles were performed on the Schlenk tubes, followed by the addition of tetrakis(triphenylphosphine)palladium(0) (0.41 g, 0.35 mmol). After three more evacuation-argon backfill cycles, the Schlenk tube was sealed and the reaction mixture was placed in an oil bath and the reaction was stirred at 110 °C. After 3 days of reaction, the mixture was cooled and filtered through Celite. The filtrate was concentrated under reduced pressure and the residue was purified by fast column chromatography (eluent ratio: 97:3 to 9:1 hexane/ethyl acetate) to afford the target product ethyl 5-bromo-6-methylnicotinate (0.41 g, 45% yield) as a solid.LRMS (m/z): 244/246 (M + 1)+.1H-NMR δ (CDCl3): 1.41 (t, J = 9.0 Hz, 3H), 2.74 (s, 3H), 4.41 (q, J = 9.0 Hz, 2H), 8.40 (d, J = 3.0 Hz, 1H), 9.01 (d, J = 3.0 Hz, 1H). |