2,5-dibromopyridine (237 mg, 1 mmol, 1.0 equiv) and phenol (140 mg, 1.5 mmol, 1.5 equiv) were added with copper powder (32.5 mg, 0.5 mmol, 0.5 equiv), cuprous iodide (95 mg, 0.5 mmol, 0.5 equiv) and cesium carbonate (978 mg. 3.0 mmol, 3.0 equiv) in N-methylpyrrolidone (NMP, 10 mL). The reaction mixture was heated to 135 °C under nitrogen protection and maintained at this temperature for 5 h of reaction. After completion of the reaction, the solid insoluble material was removed by filtration and the filtrate was concentrated. Purification by column chromatography (eluent: ethyl acetate/petroleum ether = 10/1, v/v) afforded 5-bromo-2-phenoxypyridine as a brown solid (200 mg, 84.4% yield).
