AIEE compounds based on 9,10-dithienylanthracene-substituted triphenylamine: design, synthesis, and applications in cell imaging

Abstract

Four new 9,10-dithienylanthracene-based triphenylamine derivatives (TPA-DTAs) were designed and synthesized by adjusting the linkage model of the phenylacetonitrile group with different substituents. They all displayed aggregation-induced emission enhancement (AIEE) features and large Stokes shifts (>150 nm), as well as reversible mechanofluorochromic (MFC) behaviors upon grinding-dichloromethane fuming. Substituent effects indicate that the electron-donating methoxy can efficiently increase the fluorescence quantum yield and shorten the maximum emission wavelength, while the electron-withdrawing trifluoromethyl can induce a remarkable red-shift of the emission wavelength due to the twisted intramolecular charge transfer (TICT) effect. Additionally, the TPA-DTAs displayed low cytotoxicity and have been successfully applied to living cell imaging. This work will provide a reference for the design and development of functional AIEE dyes in a wide range of applications based on the TPA-DTA-skeleton.