A straightforward preparation of fluorine-containing 1,2-dihydropyrimidines and pyrimidines with 2,2-dihydropolyfluoroalkylaldehydes

The reactions of 2,2-dihydropolyfluoroalkylaldehydes with ammonia and enol ethers or carbonyl compounds are described. In the presence of zinc chloride, all reactions took place readily in THF at 50 °C to give fluorine-containing 1,2-dihydropyrimidines in moderate to good yields. Dehydrogenation of the resulting fluorine-containing 1,2-dihydropyrimidines with tetrachloro-1,4-benzoquinone (TCBQ) or 2,3-dichloro-5,6-dicyano-1,4-benzoquinone (DDQ) at room temperature afforded the corresponding fluorine-containing pyrimidines in good yields.