Synthesis、Fluorescence Resonance Energy Transfer And Fluorescent Probes Of Perylenediimide-Based Dendrons

Perylene tetracarboxylic diimides (PDI) have recently generated great interest in the field of photonic materials, organic solar energy conversion, the photoconductor, signal amplification, fluorescence probe and liquid crystal materials, because of their excellent photo-stability, high luminescence efficiency, and novel optoelectronic properties. It will have important theoretical significance and potential application value to synthesize and study of their optical properties of this kinds of compounds. In addition, perylenediimide-based dendric molecules play special performances in the light capture systems, because of their unique structures. Therefore, the perylenediimide-based dendric compouds using in the field of ions probe will have its unique advantages and potential application values. In this paper, a series of multifunctional perylenediimide derivatives were synthesied and their fluorescence properties were studied. The main contents are as follows:1) We introduce the production of fluorescence, the mechanisms that affect the fluorescence properties of compounds, and the molecular structure characteristics and the application value of the dendrons. Then, the research progress of the dendritic PDI-based molecules and the PDI-based fluorescent probes were discussed. At last, the research significance and research content in this paper were presented.2) Two novel fluorescence resonance energy transfer-based perylenediimide-naphthalimide dendrons with perylenediimides as the energy acceptor, tertiary amines as the proton or metal receptor and naphthalimide as the energy donor were successfully synthesized. The dendrons exhibited high selectivity toward Fe3+in the presence of various other metal cations and exhibited sensitivity to protons. A 1:2 stoichiometry was found for the complex formed by the probes and Fe3+ using a Job’s plot and by non-linear least square fitting of the fluorescence titration curves. The probe molecules present abilities of fast fluorescence detection of Fe3+and for the fluorescent detection of protons with high energy transfer efficiency of 96-98%. Moreover, a novel two-photon excited perylenediimide-naphthalimide dendron (PDI-OP) has been successfully constructed. The dendron presented a rapid fluorescence response to Fe(Ⅲ) ions and 95% of two-photon energy transfer efficient (excited at 800 nm).3) A novel intramolecular fluorescence resonance energy transfer (FRET) and photo-induced electron transfer (PET) based dendritic compound PDI-BODIPY has been developed: Tetra-boron-dipyrrin (BODIPY) attached perylene bisimide by click chemistry. Compound PDI-BODIPY as a fluorescence probe for rapid, selective, and sensitive determination of Hg2+ ions has 98% of high energy transfer efficiency. The dissociation constant (Kd) of the probe PDI-BODIPY with Hg2+ is 6.67×10-12 M and the detection limit estimated from the titration results was 2×10-8M. Moreover, the imaging of Hg2+ ions in Hela cells further certified the potential value of the probe.4) A novel dual-channel dendritic chemosensor PDI-BODIPY-SS was designed and synthesized. Specific dual-channel fluorescent sensor for Hg2+ was investigated in aqueous solution, which can be deduced to the dethioacetalization reaction of BODIPY-SS promoted by Hg2+ and the coordination reaction between Hg2+ ions and the nitrogen atoms in triazole rings of PDI-BODIPY-SS. The probe PDI-BODIPY-SS was proved to selectively recognize Hg2+ ions in aqueous solution and it showed a high selectivity, a low detection limit, a short response time, and a significant fluorescence enhancement (at 610 nm) with high fluorescence resonance energy transfer (FRET) efficiency between the BODIPY-SS units as energy donor and PDI core as energy acceptor. Moreover, the energy levels of the energy donor-acceptor pairs calculated by DFT theory were used to illustrate the different FRET efficiencies of compounds PDI-BODIPY-SS and PDI-BODIPY-SS-Hg2+. Confocal fluorescence imaging of cells for detecting Hg2+in vivo was carried out successfully.5) In this study, two novel dual-switch fluorescent chemosensors based on rhodamine-peryleneiimide have been designed and synthesized. The dual-switching behaviors of the sensors were based on the structural transformations of rhodamine and an intramolecular photoinduced electron transfer (PET) process from rhodamine to perylenediimide. These probes exhibited excellent sensitivity to protons with enhanced fluorescence emission from 500 nm to 580 nm. The fluorescence changes of probes were reversible within a wide range of pH values from 2.0 to 11.0. Moreover, the sensors exhibited high selectivity, short response time, and long lifetime towards protons. The possible mechanism was investigated by the DFT calculation and1H NMR. According to the experiment of confocal laser scanning microscopy, these probes could be used to detect the acidic pH variations in living cells.6) In this chapter, a dendric compound PDI-AP based on-perylenediimide-triphenylamine derivative was designed and synthesized. The dendric molecule was fully characterized by 1H NMR, 13C NMR and HRMS-MALDI-TOF. The absorption spectra of compound PDI-AP showed a strong absorption at 375 and 576 nm, while the PDI units in compound showed weak fluorescence. Fluorescence lifetime demostrate that the value of compound PDI-AP at 610 nm decreased nearly 5 times than that of compound PDI-E at 610 nm. The calculation of energy levels of model compounds further illustrate the mechanism of the intramolecular PET process. Therefore, compound PDI-AP is an excellent light-harvesting system.7) In this paper,8 new compounds were synthesized, All the dendric molecule was fully characterized by 1H NMR, 13C NMR and HRMS-MALDI-TOF. Two novel fluorescence resonance energy transfer-based perylenediimide-naphthalimide dendrons with FRET were successfully synthesized、 A novel two-photon excited perylenediimide-naphthalimide dendron (PDI-OP) has been successfully constructed、novel dendritic probes based on perylenediimide-BODIPY have been developed 、 Two novel dual-switch fluorescent chemosensors based on rhodamine-peryleneiimide have been designed and synthesized and a dendric compound PDI-AP based on-perylenediimide-triphenylamine derivative was constructed.