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• Three bright photoactivatable fluorescence probes are developed for Cu2+ detection. • A remarkably low limit of detection (5.8 nM) for Cu2+ is obtained. • The photoactivatable probes are used for Cu2+ detection in tap water and tea samples. • The proposed method is very reliable for Cu2+ detection in real samples. Photoactivatable probes can switch fluorescence on from a weak or nonemission state to improve the sensitivity of the sensing system. In this work, we successfully constructed three highly emissive photoactivatable probes, 2-DP, 1-2-DP and 2-2-DP, for Cu2+ detection. Under UV irradiation, the photoluminescence quantum yields of 2-DP, 1-2-DP and 2-2-DP display approximately 52.4-, 11.5- and 49.2-fold enhancement, respectively. Cu2+ selectively quenches the bright photoactivated fluorescence, resulting in an approximately 38-fold fluorescence reduction. The highly selective fluorescence response to Cu2+ yields an excellent low detection limit of 5.8 nM. Moreover, the photoactivatable probes were successfully applied for Cu2+ determination in tap water and tea samples with recovery ranges of 95%–105% and 97%–106%, respectively. This work provides a more sensitive and efficient methodology for Cu2+ detection in heavy metal pollution and food safety. [ABSTRACT FROM AUTHOR]

• Novel carbazole-based dyes JY60 - 62 decorated with TPE analogues have been developed. • The introduced AIE-type TPE analogues weaken the dyes' π-π stacking in aggregation. • Increasing steric volume or decreasing distortion of TPE affords a tradeoff result. • The non-modified TPE-based JY60 achieves nearly 30% enhanced PCE than TPE-free dye. Three metal-free organic dyes JY60-62 based on triphenylethylene (TPE)-decorated carbazole have been synthesized and applied as photosensitizers in dye-sensitized solar cells. In comparison to TPE-free dye CVHTC , the anti π-π stacking characteristic stemming from the introduced TPE units helps JY60-62 to decrease the excited-state self-quenching in aggregation state and thus get better photovoltaic performance. Efforts on suppressing the unfavorable charge recombination by embellishing TPE with long hexyloxy chains (JY61), and facilitating the intramolecular charge transfer effect by improving the molecular planarity via the replacement of TPE's near-carbazole phenyl group with thiophene (JY62) seem not effective as expected, although slightly enhanced open-circuit voltage of JY61 -based devices and short-circuit current density of JY62 -based devices have been observed. Finally, the non-modified TPE-involved dye JY60 achieved the highest power conversion efficiency of 6.40%, exceeding approximate 30% of TPE-free dye CVHTC. These results reveal that original TPE unit without further redundant modification could work as an ideal building block for improving the photovoltaic properties of conventional easy-stacking dyes. [ABSTRACT FROM AUTHOR]

New tri- or tetraphenylethylene-substituted phenylcarbazole derivatives exhibiting aggregation-induced emission were synthesized by the synthetic route including Pd-catalyzed Suzuki or Buchwald-Hartwig coupling and Heck reactions. The results of evaluation of the thermal, optical, electrochemical, photophysical, and charge-transporting properties of the synthesized derivatives are presented. The compounds possess high thermal stabilities with 5% weight loss temperatures exceeding 350 °C. Some of the synthesized compounds form glasses with glass transition temperature ranging from 77 to 114 °C. Their maximum fluorescence intensity wavelengths are in the range of 472–498 nm. The highest photoluminescence quantum yield of 43.9% was observed for the solid sample of 2-(4-(4-(1,2,2-triphenylvinyl)phenylethenyl)phenyl)-9-ethylcarbazole. The electron photoemission spectra of the films of the synthesized compounds revealed ionization potentials of 5.49–5.74 eV. Hole drift mobilities in the layers of 9-phenylcarbazole para- substituted with tri- or tetraphenylethylene moities reached 10 −3 cm 2 V −1 s −1 at moderate electric fields, as established by the time-of-flight technique. [ABSTRACT FROM AUTHOR]

A series of triphenylethylene-based luminophoric molecules were efficiently synthesized. The substituent effect of the fluorophores on their photophysical properties was then investigated. Consequently, it was found that longer conjugated system and larger molecular dipole of the donor–π–acceptor fluorophores could result in bathochromic shifts of UV–vis absorption and emission bands, so do the Stokes shifts. Especially, full-color fluorescent emissions in both solution and solid states could be achieved by changing conjugation length and substituents with different electron-donating or accepting abilities in the triphenylethylene skeleton. The density functional theory calculations further demonstrated that with the increase of the electron-donating or accepting abilities of the substituents, the energy gaps of the fluorophores gradually decreased, which elucidated the substituent effect of the organic fluorophores on their photophysical properties. [ABSTRACT FROM AUTHOR]

The structural stability and the vibrational spectra of the anticancer drug tamoxifen and triphenylethylene were investigated by the DFT B3LYP/6-311G (d,p) calculations. Tamoxifen and triphenylethylene were predicted to exist predominantly as non-planar structures. The vibrational frequencies and the 1 H and 13 C NMR chemical shifts of the low energy structures of tamoxifen and triphenylethylene were computed at the DFT B3LYP level of theory. Complete vibrational assignments were provided by combined theoretical and experimental data of tamoxifen and triphenylethylene. The 1 H and 13 C NMR spectra of both molecules were interpreted by experimental and DFT calculated chemical shifts of the two molecules. The RMSD between experimental and theoretical 1 H and 13 C chemical shifts for tamoxifen is 0.29 and 4.72 ppm, whereas for triphenylethylene, it is 0.16 and 2.70 ppm, respectively. [ABSTRACT FROM AUTHOR]

Abstract: Novel dimers of triphenylethylene–coumarin hybrid containing one amino side chain were designed and synthesized by the condensation of four dicarboxylic acids with the amino monomeric hybrids catalyzed by HATU and DIPEA at room temperature. The adding order of the reactants had a significant effect on the condensation reaction when the malonic acid was used. The dimeric compounds 7a and 7b linked by the malonic acid, showed a broad-spectrum and good anti-proliferative activity against four tumor cells and low cytotoxicity in osteoblast. UV–vis, fluorescence, and circular dichroism (CD) spectroscopies and thermal denaturation exhibited that compounds 7b, 8b, 9b, and 10b had significant interactions with Ct-DNA by the intercalative mode of binding. Both the DNA binding properties and the anti-proliferative activities would be enhanced by dimerization of the monomeric hybrid with one amino side chain, and were significantly affected by the length of the linker (dicarboxylic acids). [Copyright &y& Elsevier]

Abstract: Novel triphenylethylene–coumarin hybrids containing two amino side chains were designed and synthesized. Some of these 3,4-diphenyl coumarins, 7b–c (the double chains at 4-position on 3-,4-phenyl, respectively), and 13b–f (the double chains at 4-position on 3-phenyl and 7-position, respectively), showed a broad-spectrum and good anti-proliferative activity against five tumor cells and low cytotoxicity in osteoblast. UV–vis, fluorescence, and circular dichroism (CD) spectroscopies and thermal denaturation exhibited that compounds 7b (R=piperidinyl), 7e (R=NEt2), and 7f (R=4-methylpiperazinyl) had significant interactions with Ct-DNA by the intercalative mode of binding. Structure activity relationships (SARs) analysis suggested that the location of the two amino alkyl chains would play an important role both in the compounds against tumor cells proliferation and their interactions with DNA. [Copyright &y& Elsevier]

Three triphenylethylene benzimidazole derivatives TPT-BI, TPPT-BI and TPB-BI which have aggregation-induced emission properties had been designed and synthesized. Their emission wavelengths and fluorescence intensity could be adjusted by introducing thienyl and benzene rings. And their solid-state fluorescence could be effectively tuned by mechanical grinding and solvent fuming. Furthermore, it could be applied in cell imaging as fluorochrome. [Display omitted] • Three TPT-based luminescent agents TPT-BI, TPPT-BI and TPB-BI were synthesized. • The products showed aggregation-induced emission properties and high quantum yield. • The products all exhibited reversible mechanofluorochromic performance. • The products could be applied in cell imaging as fluorochrome. Three triphenylethylene benzimidazole derivatives TPT-BI , TPPT-BI and TPB-BI with aggregation-induced emission properties were synthesized, and the effect of connecting aromatic rings was studied. Among these TPT-based luminescent agents, TPT-BI showed the biggest red-shift, which may be due to the noncoplanar structure caused by thiophene as a connection ring. TPB-BI displayed the strongest fluorescence emission intensity and the longest lifetime, which may be due to the longest conjugate chain caused by two benzene rings as connection ring. Moreover, their solid-state fluorescence could be effectively adjusted through mechanical grinding and solvent fuming, and they all exhibited reversible mechanofluorochromic performance. Furthermore, these TPT-based luminescent agents showed low toxicity and biocompatibility, so they could be used as fluorescent dyes for cell imaging. [ABSTRACT FROM AUTHOR]

Abstract: Novel triphenylethylene–coumarin hybrid derivatives containing different amounts of amino side chains were designed and synthesized in good yields under microwave radiation. The derivatives 5b–d which possessed two amino side chains (except morpholinyl) showed a broad-spectrum and good anti-proliferative activity against five tumor cells and low cytotoxicity in osteoblast. UV–vis, fluorescence, and circular dichroism (CD) spectroscopies and thermal denaturation exhibited that compounds 10c, 5c, and 13c bearing amino side chain (except morpholinyl) on 4-phenyl had significant interactions with Ct-DNA by the intercalative mode of binding. Structure–activity relationships (SARs) analysis suggested that the amino alkyl chain would play an important role both in the compounds against tumor cells proliferation and their interactions with DNA. [Copyright &y& Elsevier]

Abstract: Three new tetraphenylethylene based oligomers bearing triphenylethylene moiety were synthesized utilizing Suzuki coupling reaction and their aggregation-induced emission properties were studied. They show excellent solubility in common organic solvents and emit light in blue region (440−504nm). AIE effect is predominant for tetra-substituted TPE (20.1-fold) than mono-substituted one (4.5-fold). [Copyright &y& Elsevier]

Abstract: The electrochemical reduction of triphenylethylene (TriPE) was studied in dimethylsulfoxide (DMSO) containing 0.1M tetra-n-butylammonium perchlorate supporting electrolyte through the use of cyclic voltammetry. Experiments were conducted using two different mercury hemisphere electrode sizes (radii 3 and 25μm) and with TriPE concentrations of 0.50 and 2.00mM so as to span fully the transition from convergent to linear diffusion and steady state to transient voltammetry. Voltammetric responses obtained display two sucessive reduction waves with formal potentials separated by ca. 290mV. Taking the diffusion coeffient of TriPE, TriPE − and TriPE2− to be 2.8×10−10 m2 s−1, excellent fits between simulation and experiments were obtained across all experimental conditions, with the following DISP2 reaction scheme: Heterogeneous reactions: Homogeneous reactions: TriPE − +TriPE − ⇌TriPE+TriPE2− K DISP =1.3×10−5, kf ,DISP =5.0×104 mol−1 dm3 s−1 where k 0 denotes the standard electrochemical rate constant, α the transfer coefficient, the standard formal potential, K DISP the equilibrium constant of the disproportionation reaction, kf, DISP the rate of the forward reaction of disproportionation, Keq the equilibrium constant of the decay of TriPE2−, and kf the rate of the forward reaction of the decay of TriPE2−. [Copyright &y& Elsevier]

Considering the worth of developing non-steroidal estrogen analogues, the present research explores the pharmacophores of 1-trifluoromethyl-1,2,2-triphenylethylenes (Fig. 1) for post-coital antifertility activity using electrotopological state atom (E-state) index. The study shows the efficacy of E-state index in developing statistically acceptable model, which explains the electronic environment and topological states of different atoms in a molecule. The exploration concluded that phenyl ring attached to an ethylenic moiety, para substitution by nucleophilic group on the phenyl ring and presence of strong electronegative group as the 4th substituent on the 1st carbon of the ethylenic moiety might be crucial for activity. [Copyright &y& Elsevier]

New triphenylethylene-based derivatives, containing 2,6-di- tert -butylcarbazole or 9,9-dimethyl-9,10-dihydroacridine as donor moieties and phenylene or tetrafluorophenylene linking bridges were synthesised by Heck coupling and characterized. The synthesized compounds emitted blue light in the solid state with emission maxima in the range of 478–487 nm and photoluminescence quantum yields of 16–29%. In thermogravimetric analysis they demonstrated sublimation with 5% weight loss temperatures in the range of 307–355 °C. They exhibited glass-forming properties with glass-transition temperatures of 89–123 °C. The solid-state ionization potentials and electrochemical band gaps ranged from 5.88 to 6.37 eV and from 3.30 to 3.57 eV, respectively. Three compounds demonstrated bipolar semiconducting properties. Derivative of triphenylethylene and 2,6-di- tert -butylcarbazole with phenylene bridge showed highest hole and electron drift mobilities reaching 3.07 × 10−3 cm2/Vs and 4.2 × 10−3 cm2/Vs respectively at high electric field. Utilizing compounds in organic light‐emitting diodes as emitters external quantum efficiency of 2% was observed. ga1 • Study on neutral phenylene versus electron-accepting tetrafluorophenylene as the linking bridge. • Organic semiconductors that exhibit blue AIEE. • Organic semiconductors with bipolar charge mobilities exceeding 10 3 cm2/V∙s at high electric fields. • Non-doped sky-blue fluorescent OLEDs exhibiting external quantum efficiency of 2%. [ABSTRACT FROM AUTHOR]

Four newly synthesized tetraphenylethene or triphenylethylene-modified fluorescent dyes were reported. All synthesized luminophores displayed typical aggregation-induced emission effects, with bright and varying aggregative-state emission involving multiple fluorescence colors containing yellow, orange, green, and yellow-green. In addition, these luminogens also showed different fluorescence in the solid state. Meanwhile, their solid-state fluorescence could be effectively switched by mechanical grinding and solvent fuming except for luminogen 4. More specifically, luminogen 1 exhibited a weak mechanofluorochromic response with a color change from yellow to yellowish brown, whereas luminogen 4 displayed negligible mechanofluorochromism behavior. In stark contrast to luminogens 1 and 4 , luminogens 2 and 3 in the solid state were characterized by reversible high-contrast mechanochromic phenomena involving distinct fluorescent color changes from green to orange and from blue to yellow, respectively. These contrasting fluorescence changes were due to the morphological conversion from stable crystalline state to metastable amorphous state. Image 1 • Four fluorene or anthracene-based fluorescent dyes were synthesized. • All four compounds exhibited typical aggregation-induced emission properties. • Luminophors 1 – 4 showed varying fluorescence colors in the aggregation state. • Luminophors 1 – 4 showed tunable solid-state fluorescence. • Luminophors 1 – 4 displayed contrasting mechanofluorochromic characteristics. Synopsis: Four highly solid-state emissive compounds with typical aggregation-induced emission (AIE) properties were reported, and these luminophors displayed contrasting mechanofluorochromic characteristics. [ABSTRACT FROM AUTHOR]