反应详情

3-[4-Chloro-2-fluoro-5-(4-amino-2-trifluoromethylphenoxy)phenyl]-6-trifluoromethyl-1,2,3,4-tetrahydropyrimidine-2,4-dione (3.0 g) dissolved in anhydrous N,N-dimethylformamide (10 ml) was added to a solution of t-butyl nitrite (1.28 g) in anhydrous N,N-dimethylformamide (40 ml) kept at 60-5° C. under nitrogen. The resulting mixture was stirred for 30 minutes at this temperature. The solution was poured into water and extracted with ethyl acetate: hexane, 1:1, (300 ml). The organic phase was washed with brine and dried over anhydrous sodium sulfate. After removal of the solvent, the residue was chromatographed on silica gel eluting with ethyl acetate:hexane, 1:2. 3-[4-Chloro-2-fluoro-5-(2-trifluoromethylphenoxy)phenyl]-6-trifluoromethyl-1,2,3,4-tetrahydropyrimid-ine-2,4-dione (Intermediate 11-28) was isolated as an amorphous solid (1.64 g).

1. customkept at 60-5° C. under nitrogen
2. extractionextracted with ethyl acetate
3. washThe organic phase was washed with brine
4. dry with materialdried over anhydrous sodium sulfate
5. customAfter removal of the solvent
6. customthe residue was chromatographed on silica gel eluting with ethyl acetate