1.16 g (6.1 mmole) of copper iodide and 200 ml of anhydrous dioxane were put in a three-necked flask of 300 ml, 0.41 ml (6.1 mmole) of diaminoethane was dropped at room temperature under nitrogen flow, and the mixture was stirred for 15 minutes at room temperature and heated to 60° C. This solution was allowed to cool to room temperature, 56.8 g (244 mmole) of potassium phosphate, 12.0 g (30.5 mmole) of 1,2,4,5-tetrabromobenzene and 40.8 g (244 mmole) carbazole were added, and heated with stirring at 80° C. under nitrogen flow for 48 hours. After the reaction was completed, the reaction mixture was hot-filtered using Celite to remove insoluble matter. The filtrate was concentrated under reduced pressure. The residue was refined by NH-modified silica gel silica gel column chromatography (eluent:hexane/toluene: 1/2). The obtained crystal was repeatedly recrystallized from toluene and chloroform to give 0.90 g of a white crystal of 1,4-dibromo-3,6-di(carbazole-9-yl)benzene (yield: 5.2%). By reacting two equivalent weight of 4-(2-phenylindole-1-yl)phenyl boronic acid with this 1,4-dibromo-3,6-di(carbazole-9-yl)benzene, 1,4-di(carbazole-9-yl)-2,5-bis{4-(2-phenylindole-1-yl)phenyl}benzene was obtained. The melting point of this compound was 376° C., and the glass transition temperature was 184° C.
