Under an argon gas atmosphere, a mixture of 15.0 g (32.7 mmol) of 2-bromo-7-(4-(naphthalene-2-yl)phenyl)phenanthrene and 150 mL of dehydrated THF was cooled down to minus 60 degree C. Then, 25.3 ml (39.2 mmol) of hexane solution of 1.55M n-butyllithium was dropped into the mixture while the mixture was being stirred. The reaction mixture was further stirred at minus 60 degrees for 2 hours. The reaction solution was again cooled down to minus 70 degrees C., and 18.4 g (98.0 mmol) of triisopropylborate was dropped into the solution. The reaction mixture was warmed back to room temperature, stirred for 2 hours and left unattended for one night. Subsequently, the reaction mixture was added with aqueous solution of hydrochloric acid while being cooled on an ice bath, and stirred for 1 hour at room temperature. The reaction mixture was added with toluene, and aqueous phase thereof was eliminated. After organic phase thereof was dried with magnesium sulfate, the solvent was distilled away under reduced pressure. By recrystallizing the obtained solid with toluene-hexane, 9.5 g of 7-(4-(naphthalene-2-yl)phenyl)phenanthrene-2-ylboronic acid was obtained at an yield of 69%.
