Synthesis of substituted 5-fluoro-5, 6-dihydropyrimidines

Abstract
The reaction of 5-substituted uracils with fluorine in acetic acid and other solvents and the following treatment with different alcohols yielded the corresponding 5-fluoro-5,6-substituted-5,6-dihydropyrimidines. Thymine gave 5-fluoro-5-methyl-6-alkoxy-5,6-dihydropyrimidines. 5-Halogeno uracils and 5-nitro uracil were converted into 5-fluoro-5-halogeno-6-hydrozy-5,6-dihydropyrimidines and the 5-nitroanalogue, respectively. The structures of the compounds were confirmed by mass spectrometry.