Linear Free Energy Relationship Studies of 5-Substituted 2,4-Dioxopyrimidine Nucleosides

Article abstract of DOI:10.1021/jo00392a023

The development of a direct and efficient palladium(0)-catalyzed biaryl coupling reaction permitted the synthesis of a series of N1-substituted 5-aryl-2,4-dioxopyrimidines.The physical and spectral properties of these compounds were determined and correlated by various linear free energy relationships.The relationships between the physical and spectral data with Hammett ? constants proved useful in analyzing the electron distribution of the heterocycle.Although a significant degree of orbital overlap and interaction between the substituents and the pyrimidine ring was observed, it is doubtful that the interactions are comparable to those of a benzene ring system.