Aggregation-induced emission enhancement compounds containing triphenylamine-anthrylenevinylene and tetraphenylethene moieties

Abstract

New compounds containing triphenylamine-anthrylenevinylene and tetraphenylethene moieties are synthesized by the Wittig–Horner reaction. The compounds exhibit weak emission in good solvents, but strong fluorescence in aggregates or in the solid state, indicating that they are aggregation-induced emission enhancement compounds. The symmetry of their molecular structure affects their aggregation structures and photoluminescence emission properties in aggregation. These compounds show high thermal stabilities with glass transition temperatures between 168–177 °C and decomposition temperatures between 521–537 °C. The HOMO levels of the compounds are in the region of 4.92–4.94 eV, very close to the work function of indium tin oxide anode (4.8–5.0 eV). One of the compounds exhibits obvious piezofluorochromic behavior. The piezofluorochromic nature is generated through changing the mode of molecular packing under external pressure.