To 221 mg of dichlorobis(triphenylphosphine)palladium, 60 mg of copper iodide, and 1.24 g of N-(3-butynyl)phthalimide were added 15 ml of tetrahydrofuran, 1.50 g of the 2-phenyl-4-bromothiazole obtained in the foregoing stage, and 3.8 ml of triethylamine in a nitrogen atmosphere, and the mixture was stirred under reflux for 4 hours. After the stifling, the reaction mixture was cooled to room temperature and the solids were filtered. After concentrating the filtrate, the residue was purified by column chromatography (Wakogel C-200; toluene:ethyl acetate=9:1) to give 1.24 g of a phthalimide compound.
