Synthesis and study of N,N′-disubstituted derivatives of pyromellitic diimide

New N, N′-bis(4,6-dimethylpyrimidin-2-yl)- and N, N′-bis(2,3,5,6-tetrafluorophenyl)-substituted pyromellitic diimides were synthesized. Their properties were studied in comparison with the previously synthesized N, N′-bis(4-fluorophenyl)pyromellitic diimide. Thermogravimetry, UV spectroscopy, cyclic voltammetry, and quantum chemical calculations in the framework of the density functional theory were used to characterize the synthesized compounds. The introduction of the pyrimidine cycle significantly decreases the energy of the lowest unoccupied molecular orbital. The highest occupied molecular orbitals in all compounds synthesized are deep-lying (about −7 eV).