Abstract:The amphiphilic carboxylic acid derivatives, 5-[(4-(diphenylamino)phenyl)]thiophen-2-carboxylic acid and its potassium salts (TTC-H and TTC-K), were synthesized through a Suzuki coupling reaction involving 5-bromothiophen-2-carboxylic acid and [(4-(diphenylamino)phenyl)]boric acid. The structures of the two compounds were characterized by 1HNMR and 13CNMR. The UV-Vis absorption spectroscopy was used to verify the photophysical properties of TTC-H and TTC-K, while fluorescence emission spectroscopy systematically discussed their aggregated states. Density-functional theory calculations and solvation colorimetric effects confirmed the charge transfer properties within the molecules of TTC-H and TTC-K. Their crystal structures were resolved and analyzed by Hirshfeld surface analysis, and the results showed that there were weak interaction forces between TTC-H molecules, such as C···H (31.6%, accounting for the percentage of the total interaction force, similarly hereinafter), H···H (44.6%) and O···H (14.6%). Both TTC-H and TTC-K possessed the property of aggregation-induced emission (AIE). The aqueous solution of TTC-K was proved effective in revealing the tertiary structure of latent fingerprints through chemical impregnation and atomization methods with a good stability of aging. And even at low concentrations (5×10-5 mol/L), the TTC-K aqueous solution reagent enabled rapid identification of latent fingerprints (≤5 s) by chemical impregnation method. And both old fingerprints (≤14 d) and fingerprints soaked in water (≤7 d) have good imaging effects.