1,2-Dichlorobenzene (4.5 ml) was added to 5,6-dimethyl-2-phenyl-pyridin-3-ol (267 mg), 4-chloro-6,7-dimethoxyquinoline (100 mg), and 4-(N,N-dimethylamino)pyridine (164 mg), and the mixture was stirred at 140° C. for 8 hr. The reaction solution was cooled to room temperature, and the solvent was then removed by distillation under the reduced pressure. Water was added to the residue, and the mixture was extracted with chloroform. The chloroform layer was washed with water and was dried over anhydrous sodium sulfate. The solvent was removed by distillation under the reduced pressure, and the residue was purified by thin layer chromatography using hexane-acetone to give the title compound (159 mg, yield 92%).
