In the present study,the density functional theory(DFT)and Gibbs free energy calculations were performed to investigate the stability and tautomerism of C4-substituted-3,4-dihydropyrimidin-2(1H)-ones.Three different f...In the present study,the density functional theory(DFT)and Gibbs free energy calculations were performed to investigate the stability and tautomerism of C4-substituted-3,4-dihydropyrimidin-2(1H)-ones.Three different forms are possible for the ethyl 3,4-dihydropyrimidinones(ethyl 4-aryl-6-methyl-3,4-dihydropyrimidin-2(1H)-one-5-carboxylates,ethyl 4-aryl-2-hydroxy-6-methyl-1,4-dihydropyrimidine-5-carboxylates and ethyl 4-aryl-2-hydroxy-6-methyl-3,4-dihydropyrimidine-5-carboxylates)forms that the most stable form is ethyl 4-aryl-6-methyl-3,4-dihydropyrimidin-2(1H)-one-5-carboxylates(keto-form).The obtained data showed that the substitution on the C4-substitut position can be effective on the equilibrium constant(K_(eq)).展开更多
文摘In the present study,the density functional theory(DFT)and Gibbs free energy calculations were performed to investigate the stability and tautomerism of C4-substituted-3,4-dihydropyrimidin-2(1H)-ones.Three different forms are possible for the ethyl 3,4-dihydropyrimidinones(ethyl 4-aryl-6-methyl-3,4-dihydropyrimidin-2(1H)-one-5-carboxylates,ethyl 4-aryl-2-hydroxy-6-methyl-1,4-dihydropyrimidine-5-carboxylates and ethyl 4-aryl-2-hydroxy-6-methyl-3,4-dihydropyrimidine-5-carboxylates)forms that the most stable form is ethyl 4-aryl-6-methyl-3,4-dihydropyrimidin-2(1H)-one-5-carboxylates(keto-form).The obtained data showed that the substitution on the C4-substitut position can be effective on the equilibrium constant(K_(eq)).