A mixture of 3-(2-pyridyl)-5-(3-bromo-5-fluorophenyl)-1,2,4-oxadiazole (100 mg, 0.312 mmol), pyridine-3-boronic acid 1,3-propanediol cyclic ester (102 mg, 0.624 mmol), and tetrakis(triphenylphosphine)palladium(O) (Pd(PPh3)4, 35.8 mg, 0.031 mmol), in a solution of ethylene glycol dimethyl ether (3 mL) and 2M sodium carbonate (3 mL) was heated in a sealed vial at 100° C. for 1 hour. The reaction was cooled, diluted with chloroform, washed with water and saturated brine, filtered, and concentrated. Silica gel chromatography using a gradient of 50% ethyl acetate in hexane to 100% ethyl acetate afforded 19 mg (19%) 3-(2-pyridyl)-5-(3-fluoro-5-(3-pyridyl)phenyl)-1,2,4-oxadiazole: 1H-NMR (CDCl3), δ (ppm): 8.92 (s, 1H), 8.84 (d, 1H), 8.70 (d, 1H), 8.39 (s, 1H), 8.25 (d, 1H), 8.00 (m, 2H), 7.90 (td, 1H), 7.65 (m, 1H), 7.55 (m, 2H).
