Construction And Properties Of 9,10-diarylanthracene-based Luminescent Materials Based On AIE Mechanism

Traditional organic luminescent materials often face high concentration aggregated states in practical applications and resulted in aggregation-caused quenching(ACQ)effect,which greatly limits their applications in practice.In 2001,Tang Benzhong's team discovered that silole derivatives emit intense luminescence at high concentrations,but almost no luminescence at low concentrations.They named this phenomenon as aggregation-induced emission(AIE).The discovery of AIE behaviors solved the ACQ problem,which faced by traditional luminescent materials in practical applications,and expanded the application range of organic luminescent materials and aroused the interest of many researchers.This made the subsequent research on AIE materials become a hot direction in this field.Anthracene,as a kind of polycyclic aromatic hydrocarbons with rich ?-conjugation system,is one of the earliest molecules to be developed as organic luminescent materials,but it is also affected by the ACQ effect.In this paper,a series of AIE luminescent molecules based on anthracene were designed to explore the effects of different modification strategies on AIE and mechanofluorochromic and their applications in cell imaging were also studied.The specific research contents are as follows:1.Symmetric thiophenylanthracene derivatives DBTA-DO,DBTA,and DTA-DO were designed and synthesized.All of them have excellent AIE behaviors.Through the study of fluorescence and UV absorption spectra,it was found that the introduction of S,S-dioxide and rigid aryl rings could significantly increase the emission wavelength of them,while without affecting the UV absorption.All the three compounds exhibited mechanofluorochromic properties under external force stimulation.By studying the crystal structure of DTA-DO revealed that the highly distorted non-coplanar conformation caused by intermolecular hydrogen bonding may be the main reason for AIE properties.Meanwhile,DTA-DO has good biocompatibility and can be used for cell imaging.2.The asymmetric thiophenylanthracene derivatives containing formyl CTA-P,CTA-MOP and CTA-TFMP were designed and synthesized.All of them showed good AIE properties with strong intermolecular aggregation at 90% water fraction.Meanwhile,different substituents could modulate the luminescence of them.These compounds also showed mechanofluorochromic behaviors under external force stimulation,and the fluorescence of CTA-TFMP and CTA-MOP completely restored to the initial state after fumigation with dichloromethane indicating reversible mechanofluorochromic properties.In addition,CTA-TFMP and CTA-MOP are also used in cell imaging and have good biocompatibility.3.Three thiophenylanthracene derivatives TFPTA-Py,MOPTA-Py,and PTA-Py with mitochondrial localization function group were designed and synthesized.All of them have large Stokes shift,and their solutions shows strong red fluorescence under 365 nm light irradiation.Besides,they all exhibit good mechanofluorochromic properties under external force,and the fluorescence emission wavelength of TFPTA-Py could be restored to the initial state after five minutes of dichloromethane fumigation.They also have good biocompatibility and can be used as fluorescent dye for cell imaging.The Mander overlap coefficient and Pearson co-localization coefficient of PTA-Py were determined to be 0.92 and 0.91,respectively,indicating that PTA-Py has a good targeting function to mitochondria in cells.