To a solution of 6-fluoropyridin-2-ylboronic acid (289.0 mg, 2.05 mmol) in dioxane (1 mL) was added methyl 2-chloro-3-(isopropyl(methyl)amino)quinoxaline-6-carboxylate (300.0 mg, 1.02 mmol), K3PO4 (434.0 mg, 2.05 mmol), and Pd(PPh3)4 (27.6 mg, 0.02 mmol) under nitrogen atmosphere. After stirring 1 h at 90° C., the reaction mixture was dissolved in water (50 mL), extracted with dichloromethane (3×20 mL), dried over anhydrous magnesium sulfate and concentrated under reduced pressure to afford a residue, which was purified by a silica gel column with 0.05%-0.2% ethyl acetate in petroleum ether to afford methyl 2-(6-fluoropyridin-2-yl)-3-(isopropyl(methyl)amino)quinoxaline-6-carboxylate as a light yellow solid (260.0 mg, 72%).
