Into a 200-mL three-neck flask were put 1.0 g (2.6 mmol) of 9-(4-bromophenyl)-10-phenylanthracene, 0.86 g (2.6 mmol) of 3-(dibenzofuran-2-yl)-9H-carbazole, and 0.50 g (5.2 mmol) of sodium tert-butoxide. The air in the flask was replaced with nitrogen, and then, to the mixture were added 50 mL of toluene and 0.20 mL of tri(tert-butyl)phosphine (a 10 wt % hexane solution). This mixture was degassed under reduced pressure while being stirred, and then 75 mg (0.13 mmol) of bis(dibenzylideneacetone)palladium(0) was added to this mixture. This mixture was stirred at 110° C. for 2 hours under a nitrogen stream. After the stirring, this mixture was subjected to suction filtration through Celite, alumina, and Florisil. The obtained filtrate was concentrated to give a light-yellow oily substance. This oily substance was recrystallized from toluene/hexane to give 1.4 g of light-yellow powder in 80% yield. The synthesis scheme of Step 4 is shown in (a-4).
