In argon atmosphere, a mixture of 18.53 g (87.4 mmol) of 2-dibenzofuranboronic acid, 25.00 g (87.4 mmol) of 2,6-dibromonaphthalene, 5.05 g (4.40 mmol) of tetrakis(triphenylphosphine)palladium (0), 300 ml of dimethoxyethane, and 132 g of a 2 M sodium carbonate aqueous solution was stirred at a bath temperature of 85° C. for 7 h. The reaction mixture was added with water and extracted with toluene. After washing with water, the organic phase was dried over magnesium sulfate. Then, the solvent was removed by distillation under reduced pressure, and the residue was purified by silica gel chromatography to obtain 13.20 g (yield: 38%) of 2-(6-bromonaphthalene-2-yl)dibenzofuran.
