An Electron-Deficient Discotic Liquid-Crystalline Material

Hexaazatriphenylene-hexacarboxy triimide 1 was synthesized and fully characterized using NMR, IR, UV/vis, and fluorescence spectroscopy. DSC and polarization microscopy showed compound 1 to be liquid crystalline over a large temperature range, while its specific mesophase (Col ho ) could be determined via X-ray scattering experiments. Although the first reduction potential of 1 could not be measured directly, two closely related reference compounds 4 and 5 featured low first reduction potentials, suggesting the suitability of 1 as an acceptor material in photoinduced electron-transfer processes. The latter was confirmed via photoinduced absorption and fluorescence spectroscopy on mixed films of 1 and poly(3-hexylthiophene).