Triphenodioxazine Diimides: Design, Synthesis, and Properties

To increase solubility and decrease the lowest unoccupied molecular orbital (LUMO) energy levels of triphenodioxazine (<b>TPDO</b>), a novel series of imide-fused <b>TPDO</b> derivatives (<b>TPDODIs</b>) were designed, synthesized, and investigated. The introduction of alkyl diimide groups endows <b>TPDODIs</b> with high solubility and LUMO energy levels below -3.90 eV. <b>TPDODIs</b> also show strong absorption in the visible region with high maximum molar extinction coefficients and high fluorescence quantum yields (0.67 and 0.71, respectively). Moreover, <b>TPDODIs</b> display thermotropic liquid-crystalline behavior as indicated by spindly nematic or dendritic textures. Their high solubility and low LUMO levels suggest these materials are well-suited for solution-processable n-type electronic devices.