Synthesis, properties, and applications of novel 9,10-diarylanthracene-based D-A type AIEE fluorescent materials.

Two novel aggregation-induced emission enhancement (AIEE) active donor-π-acceptor (D-π-A) molecules, namely TP-ATA and CP-ATA, were rationally designed and synthesized. In these two molecules, triphenylamine and carbazole act as electron-donating skeletons, while terminal thiophene-acrylonitrile groups function as electron-withdrawing moieties. Both compounds exhibit distinct solvatochromic behaviors, verifying their intrinsic intramolecular charge transfer (ICT) characteristics. In addition, TP-ATA and CP-ATA possess reversible mechanofluorochromic (MFC) properties. Upon grinding, TP-ATA displays a more prominent fluorescence color transition from bright green to bright yellow, accompanied by an emission redshift of 35 nm, which is more significant than that of CP-ATA. X-ray diffraction characterization confirms that the disturbed molecular packing after grinding can be completely restored via fuming with dichloromethane. This molecular fluorophore modulation strategy provides an effective approach to tuning the photophysical properties of anthracene-based D-π-A molecules. Taking advantage of their good solid-state luminescence performances, both molecules have been successfully applied to the visualization of latent fingerprints on various substrates. Furthermore, cellular fluorescence imaging experiments demonstrate that CP-ATA can efficiently penetrate cell membranes to achieve intracellular fluorescence imaging, indicating its promising application potential in the biological field.