To a solution of 5,7-dichloro-2-[4-(2-hydroxy-ethoxy)-3,5-dimethylphenyl]-3H-quinazolin-4-one (1.14 g, 3.00 mmol) in anhydrous DMF (15 mL) was added carbon tetrabromide (1.10 g, 3.30 mmol). Then, triphenylphosphine (0.86 g, 3.30 mmol) was added in small portions. The reaction mixture was stirred at room temperature for 16 hours under nitrogen. Solvent was evaporated under reduced pressure. The residue was washed with ethyl acetate (50 mL) and dried under vacuum to give 2-[4-(2-bromo-ethoxy)-3,5-dimethylphenyl]-5,7-dichloro-3H-quinazolin-4-one as a white solid. Yield: 0.46 g (35%).
