A novel thiophene-fused polycyclic aromatic with a tetracene core: synthesis, characterization, optical and electrochemical properties

FeCl?-mediated oxidative cyclization was successfully used to construct an extended thiophene-pendant pyrene skeleton and synthesize a novel thiophene-fused polycyclic aromatic (THTP-C) with a tetracene core. The identity of the compound was confirmed by 1H-NMR, 13C-NMR, MS, and elemental analysis. Meanwhile, a single crystal of THTP-C was obtained and analyzed by X-ray single-crystal diffraction. THTP-C has a "saddle" shaped π-conjugated 1-D supramolecular structure, and favors highly ordered self-assembly by π-π interactions as evidenced by its concentration-dependent 1H-NMR spectra in solution. The optical properties of THTP-C were investigated by ultraviolet-visible (UV-Vis) and photoluminescence (PL) spectroscopy and its electrochemical properties were investigated by cyclic voltammetry (CV). The relatively large band gap (2.86 eV), low E(HOMO) level (-5.64 eV) and intermolecular π-π interactions imply that THTP-C has a high stability against photo-degradation and oxidation, and may be a promising candidate for stable hole-transporting materials.