A mixture of 2-amino-4,6-difluoro-benzamide (0.96 g, 5.60 mmol), 4-(2-hydroxy-ethoxy)-3,5-dimethyl-benzaldehyde (1.09 g, 5.60 mmol), NaHSO3 (58.5 wt %, 1.00 g, 5.60 mmol) and p-toluenesulfonic acid monohydrate (1.44 g, 7.06 mmol) in N,N-dimethylacetamide (25 mL) was stirred at 120° C. for 16 hours, then cooled to room temperature. Solvent was removed under reduced pressure. The residue was diluted with water (100 mL). The solid separated was filtered and washed with water and dried under vacuum to give 5,7-difluoro-2-[4-(2-hydroxy-ethoxy)-3,5-dimethyl-phenyl]-3H-quinazolin-4-one as a white solid. Yield: 1.55 g (79%).
