A mixture of 2,4,6-trichloropyrimidine (PYR, 1.3 mL, 7 mmol) and phenylboronic acid (Ph-B(OH)2, 1.5 g, 12 mmol), catalyzed by Pd(PPh3)4 (0.2 g, 0.17 mmol), was mixed in 40 mL of toluene. The mixture was transferred to a two-necked round-bottomed flask equipped with a condenser tube, and 2 M aqueous K2CO3 (40 mL), ethanol (25 mL), and toluene (80 mL) were added, and the reaction was carried out at reflux for 8 h at 110 °C under nitrogen protection. After completion of the reaction, the mixture was extracted with ethyl acetate (60 mL) and water (50 mL). The organic layer was dried with anhydrous magnesium sulfate, filtered and concentrated. The crude product was purified by silica gel column chromatography with hexane:dichloromethane (4:1) as eluent to give the intermediate 2P-PYR as a white solid. 2-Chloro-4,6-diphenylpyrimidine was further synthesized in 74% yield; white solid; 1H NMR (500 MHz, CDCl3) δ 8.13-8.14 (m, 4H), 8.01 (s, 1H), 7.51-7.55 (m, 6H); 13C NMR (500 MHz, CDCl3) δ 167.7, 162.1, 135.7, 131.7, 129.1, 127.5, 111.0.
