A mixture of compound 11 (135 mg, 0.5 mmol), 4-chloropyridine hydrochloride (107 mg, 0.713 mmol), tetrakis(triphenylphosphine)palladium (45 mg, 0.04 mmol) and Na2CO3 (160 mg, 1.51 mmol) in dimethoxyethane (2.2 mL) and water (0.7 mL) mixture, is heated to 85° C. for 5 h. The mixture is cooled to rt and partitioned between water and EtOAc. The organic phase is dried using Na2SO4 and concentrated on rotary evaporator to afford 100 mg (59%) of compound 13. 1H NMR (300 MHz, CDCl3) δ 8.68-8.62 (m, 2H), 7.80-7.42 (m, 2H), 7.40-7.35 (m, 1H), 7.36-7.24 (m, 1H), 7.18-7.08 (m, 1H), 5.26-5.18 (br s, 1H), 4.25 (d, J=5.5 Hz, 2H), 1.44 (s, 9H).
