Step A: 4-Bromopyridine (3.0 g, 19.0 mmol), 4-methoxycarbonylphenylboronic acid (2.63 g, 14.6 mmol), Pd(PPh3)2Cl2 (0.35 g, 0.5 mmol) and sodium carbonate (6.91 g, 65.2 mmol) were dissolved in 1,2-dimethoxyethane (40 mL) under nitrogen protection. The reaction mixture was heated to 90 °C and stirred for 10 hours. Upon completion of the reaction, the mixture was concentrated under reduced pressure and the residue was purified by silica gel column chromatography (eluent: petroleum ether/ethyl acetate = 6:1 to 2:1) to afford methyl 4-(pyridin-4-yl)benzoate (2.7 g, yield: 86.8%) as a white solid. m/z MS (ESI): 214 [M+H]+.
