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We designed and synthesized three new tetraphenylethene (TPE) derivatives ( CZ-TPE , DMA-TPE and TPA-TPE ) modified with different electron rich group (carbazole, N, N -dimethylaniline and triphenylamine segments, respectively) by Knoevenagel condensation reaction. The chemical structures of these compounds are identified by NMR, MS and IR. The absorption and emission of these dyes were investigated by UV-Vis and fluorescence spectroscopy, respectively. The results shown three dyes exhibited evident aggregation-induced emission (AIE) or aggregation-induced emission enhancement (AIEE) properties with wavelength tunable emission. Their emission color can be tuned from green to orange in tetrahydrofuran/H 2 O solutions, from green to red in solid state or pure tetrahydrofuran solutions. In addition, the solution or film of TPA-TPE shown results in distinct fluorescence from “ON” to “Off” observation as well as color change from orange yellow to colorless by naked eyes when the addition of toxic Cl 2 gas, which can be used as an excellent dual chromo- and fluorogenic signal changes that is well suited for monitoring Cl 2 gas in solution, or solid film, conveniently. These results indicate TPA-TPE is a promising candidate chemosensor for the detection of Cl 2 gas. [ABSTRACT FROM AUTHOR]

We designed and synthesized photochromic fluorescent poly (MMA-co-SPO-co-TPE) nanoparticles with pendant spirooxazine (SPO) dye and tetraphenylethylene (TPE) fuorophores attached to poly (methyl methacrylate) (MMA) backbone by semi-continuous polymerization. The polymerization reactions were accomplished in water with randomly methylated-β-cyclodextrin (β-CD) at 80 °C in the presence of potassium peroxodisulfate which can be used as free radical initiator. This new synthetic method leads to uniform and smooth nanoparticles with a narrow particle size distribution. In addition, the poly (MMA-co-SPO-co-TPE) nanoparticles exhibit aggregation induced emission (AIE) properties and excellent photochemical properties because of spirooxazine dyes convert reversibly to merocyanine form upon ultraviolet (UV) irradiation, which active the intramolecular energy transfer pathway and quench the fluorescence of TPE in polymers. Consequently, the fluorescence of the poly (MMA-co-SPO-co-TPE) nanoparticles can be reversibly switched “on” and “off” upon UV and visible light, which maybe have potential application in biological fluorescent labeling as well as in optical fields like individually light–addressable nanoscale devices. [ABSTRACT FROM AUTHOR]

We designed and synthesized two new visible light triggered photochromic and aggregation-induced emission compound derived from the third generation donor−acceptor Stenhouse adducts (DASAs) with indoline-tri/tetra-phenylethylene moiety (abbreviation: SPE-IF/TPE-IF). The chemical structures of these compounds are identified by NMR, MS and so on. The key intermediate SPE-ID/TPE-ID as donor showed excellent AIE properties in water-THF (v/v) solutions. The absorption and emission of SPE-IF/TPE-IF were investigated by UV–Vis and fluorescence spectroscopy, respectively. The results shown they exhibited photochromic with fatigue resistance and fluorescent switching properties with visible light regulation. The open/colored triene and closed/colorless cyclopentenone isomers of SPE-IF/TPE-IF were equipped with high photo bleaching and fluorescence effect upon alternating visible light irradiation and heating both in solution and in PMMA doped solid state. And the solvent dependence effect of TPE-IF was studied. The photochromic mechanism of SPE-IF/TPE-IF was also basically investigated by computational method. These results indicate SPE-IF or TPE-IF is a promising candidate for visible light-responsive smart materials. Image 1 • The third generation DASAs with AIE including SPE-IF/TPE-IF were synthesized. • The fluorescence switching of SPE-IF/TPE-IF was investigated both in solvent and doped in PMMA film. • The equilibration kinetics and solvent effect of the TPE-IF were studied. [ABSTRACT FROM AUTHOR]

Abstract In this work, we designed and synthesized a novel asymmetric tetraphenylethylene-based fluorescence compound, which can form cholesteryl liquid crystal by cooling from the isotropic melt and exhibit typical AIE property with a 180-fold enhancement of fluorescence intensity in 90% water fraction of THF/water mixture than pure THF. This compound can gelate in cyclohexane via both ultrasound stimuli and general sol–gel processes accompanied by remarkable enhanced fluorescence emission. The self-assembly and gelling properties can be controlled by ultrasound stimuli and renewed by a thermodynamic process. The mechanism of the process was investigated by UV–Vis absorption, PL emission, scanning electron microscopy, wide-angle X-ray scattering analysis, and small-angle X-ray scattering analysis. The results reveal that the cooperation and relative competition of multiple intermolecular interactions, which are the main contributors for the formation of gel influenced by the sonication or thermal stimulus. Graphical abstract Image 1 Highlights • A novel asymmetric tetraphenylethylene-based compound was synthesized. • The compound can form cholesteryl liquid crystal and exhibit enhanced emission via both ultrasound and thermal stimuli. [ABSTRACT FROM AUTHOR]

Two novel aggregation-induced emission compounds harnessing Excited-State Intramolecular Proton Transfer process based on salicylideneaniline derived from tetraphenylethylene and cholesterol moieties were synthesized and characterized. One of the compounds could gelate in cyclohexane exhibiting gelation-induced enhanced emission and the emission intensities can be reversibly changed with the gel-solution transition by alternate cooling and heating. Moreover, this compound showed photochromic behavior both in gel and solid states under UV light irradiation due to the loose packing of the molecules and permitting the molecule to rotate, which may be a potential candidate for external stimuli-responsive materials through tuning the self-assembly process of the functional gelator. [ABSTRACT FROM AUTHOR]