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Resonant electron capture by aza and diaza derivatives of phenanthrene (7,8-benzoquinoline and 1,10-phenanthroline) and anthracene (acridine and phenazine) at incident free electron energies (Ee) in the range of 0–15 eV was studied. All compounds except 7,8-benzoquinoline form long-lived molecular ions (M−) at thermal electron energies (Ee ∼ 0 eV). Acridine and phenazine also form such ions at epithermal electron energies up to Ee = 1.5–2.5 eV. The lifetimes (τa) of M− with respect to electron autodetachment are proportional to the extent of aza-substitution and increase on going from molecules with bent geometry of the fused rings (azaphenanthrenes) to linear isomers (azaanthracenes). These regularities are due to an increase in the adiabatic electron affinities (EAa) of the molecules. The EAa values of the molecules under study were comprehensively assessed based on a comparative analysis of the measured τa values using the Rice–Ramsperger–Kassel–Marcus theory, the electronic structure analysis using the molecular orbital approach, as well as the density functional calculations of the total energy differences between the molecules and anions. The only fragmentation channel of M− ions from the compounds studied is abstraction of hydrogen atoms. When studying [M–H]− ions, electron autodetachment processes were observed, the τa values were measured, and the appearance energies were determined. A comparative analysis of the gas-phase acidity of the molecules and the EAa values of the [M–H]· radicals revealed their proportionality to the EAa values of the parent molecules. [ABSTRACT FROM AUTHOR]

Dual‐state emission luminescent materials (DSEgens), which exhibit bright emissions in boththe solid state and solution, have been attracting research interest in the design of multifunctional materials.The delicate manipulation of molecular structures remains challenging in the synthesis of DSEgens. In this article, two novel molecules with dual‐state emission were synthesized by combining tetraphenylethylene with anthracene via dihydroisoxazole. Tetraphenylethylene acts as a solid‐state emitter, while the anthracene core functions as an emitter in the solution state to achieve DSE fluorescence properties. The THF/DCM mixture resulted in successfully obtaining the crystal structures of TPE−An−H and TPE−An−Cl. The quantum yields (QYs) of TPE−An−H were 31 % and 42 % in EA and the solid state, respectively, while TPE−An−Cl exhibited QYs of 32 % and 34 %. The novel synthesis method in this paper combines AIE with ACQ via dihydroisoxazole to achieve dual‐state emission, offering a new and concise approach. [ABSTRACT FROM AUTHOR]

Thermally activated delayed fluorescence (TADF) materials with the through‐space charge transfer (TSCT) effects can provide a useful approach to efficiently utilize dark state triplet excitons through an efficient reverse intersystem crossing process. TSCT‐TADF emitters PCzoTrz‐ICz with small ∆EST values and high photoluminescence quantum yield is designed and synthesized using common acceptor triazine, donor 3,6‐diphenylcarbazole and Indolo[3,2,1‐jk]carbazole which is a rigid π‐conjugated group with high triplet state and high thermal stability. The doped‐organic light‐emitting diodes using PCzoTrz‐ICz as emitters exhibit high tolerance to host with different polarity and charge transport properties, and PCzoTrz‐ICz doped devices in 2,8‐bis(diphenylphosphoryl)dibenzofuran even realizes a maximum external quantum efficiency (EQEmax) of 32.5% and maximum current efficiency (CEmax) of 74.1 cd A−1, which is higher than EQEmax of 28.1% and CEmax of 64.8 cd A−1 of PCzoTrz. Moreover, PCzoTrz‐ICz can be used as highly efficient sensitizers for narrow band blue emitter of v‐DABNA, and achieves more than EQEmax of 33.3%, maximum luminance of 26,291 cd m−2, CEmax of 42.7 cd A−1 and blue index of 237 cd A−1 CIEy−1. [ABSTRACT FROM AUTHOR]

Three carbazole‐substituted anthracene 2CbzAn, 26CbzAn, and 246CbzAn have been developed. The introduction of these carbazole substituents could generate more triplet states with energy levels close to 2× E(T1) that could successfully facilitate the triplet‐triplet annihilation upconversion (TTA‐UC) process to achieve high upconversion quantum yield (UCQY). This observation aligns with the Adachi theory about TTA‐UC mechanisms. In organic light‐emitting diode (OLED) device investigation, in a non‐doped state show an external quantum efficiency (EQEmax) of 5.82% with exceptional pure‐blue emission (CIEy of 0.101), and the DPaNIF doped DMPPP/26CbzAn bilayer structure reaches an impressive EQEmax of 11.12%. [ABSTRACT FROM AUTHOR]

Organic light-emitting diodes (OLEDs) have emerged as one of the dominant technologies in displays due to their high emission efficiency and low power consumption. However, the development of blue color emitters has fallen behind that of red and green emitters, posing challenges in achieving optimal efficiency, stability, and accessibility. In this context, thermally activated delayed fluorescence (TADF) emitters hold promise as a potential solution for cost-effective, exceptionally efficient, and stable blue OLEDs due to their potential high efficiency and stability. TADF is a principle where certain organic materials can efficiently convert both singlet and triplet excitons, theoretically achieving up to 100% internal quantum efficiency. This research focused on diphenyl sulfone derivatives with carbazole groups as TADF compounds. Quantum chemical calculations and photoluminescence properties show the potential TADF properties of the molecules. New materials exhibit glass transition temperatures that would classify them as molecular glasses. Depending on the structure of the molecule, the photoluminescence emission is in the blue or green spectral region. Organic light-emitting diodes were fabricated from neat thin films of emitters by the wet casting method. The best performance in the deep blue emission region was achieved by a device with a turn-on voltage of 4 V and a maximum brightness of 178 cd/m2. In the blue-green emission region, the best performance was observed by an OLED with a turn-on voltage of 3.5 V, reaching a maximum brightness of 660 cd/m2. [ABSTRACT FROM AUTHOR]

Diels‐Alder (DA) cycloaddition of chalcones to anthracene and its 9‐substituted derivatives is an example of a demanding reaction that is not effective even under increased pressure. In this article we show that an easily accessible complex cation [Co(CH3NO2)6]2+ stabilized by weakly coordinating anion [Al(OC(CF3)3)4]− exhibits good catalytic activity in the reaction. Our screening covering chalcone and anthracene derivatives with either activating or deactivating effects on reactivity in DA cycloadditions show that the catalyst allows to obtain [4+2] cycloadducts with yields up to 99 % under mild conditions, even for 9‐bromoanthracene – a very poor diene in DA reactions. The reaction proceeds best in liquid SO2, which is an unusual solvent for this type of reaction. 9‐methylanthracene ‐ the most reactive diene among those tested in the study ‐ gives two regioisomeric cycloadducts and their ratio depends on the solvent used. Modeling of the reaction with DFT methods shows that Co(II) significantly lowers the activation energy of the cycloaddition. In the case of 9‐bromoanthracene the effect is much more pronounced than with e. g. recently reported redox‐activation of the diene, which is in agreement with much better yields obtained with the use of the cobalt catalyst. [ABSTRACT FROM AUTHOR]

Efficient organic blue materials are essential to develop highly efficient organic light-emitting diodes. However, there is a challenge to commercialize efficient blue compounds due to the fundamentally wide band gap and the lack of pure blue emitters. In this study, the new anthracene-based fluorescent emitter, (4-(10-(4-(9H-carbazol-9-yl)-2-methylphenyl)anthracen-9-yl)-3-methylphenyl)diphenylphosphine oxide (CZm-AN-mPO) was designed and synthesized. The thermal, photophysical and electrochemical properties of the CZm-AN-mPO were systematically investigated. The CZm-AN-mPO exhibits a deep-blue emission at 425 nm and AIE property with a relatively narrow full-width at half maximum of 34 nm. The CZm-AN-mPO based non-doped devices show pure blue emission. The optimized OLEDs indicated maximum external efficiencies of 4.3% and 4.2% at emission layer thickness of 20 nm and 40 nm, respectively. [ABSTRACT FROM AUTHOR]

Organic semiconductors (OSCs) are widely used in flexible display, renewable energy, and biosensors, owing to their unique solid-state physical and optoelectronic properties. Among the abundant crystal library of OSCs, asymmetric aryl anthracene derivatives have irreplaceable advantages due to the interplay between their distinct π-conjugated geometry and molecular stacking as well as efficient light emission and charge transport properties that can be simultaneously utilized. However, the poor crystal stacking patterns of most asymmetric molecules limit their utility as excellent OSCs. Thus, it is crucial to clarify the structural features that enable the extremely ordered stacking and favorable electronic structure of asymmetric anthracene derivatives to become high-performance OSCs. This contribution investigates the charge transport properties of a series of asymmetric aryl anthracene derivatives to reveal the modulation factors of the molecular stacking modes and to explore the structural factors, which are beneficial to charge transport. The analysis demonstrated that the vinyl-linker facilitated the injection of hole carriers, and the alkynyl-linker effectively reduces the reorganization energy. Importantly, the linear polarizability and permanent dipole moment of a single molecule play a vital regulation to molecular stacking modes and the transfer integral of the dimer. The "head-to-head stacking" motif shows a compact stacking pattern and the maximum 2D anisotropic mobility more than 10 cm2 V−1 s−1. These findings sharpen our understanding of the charge transport properties in asymmetric organic semiconductors and are essential for developing a diverse range of high-performance OSC materials. [ABSTRACT FROM AUTHOR]

The utilization of organic crystals in visible light communication (VLC) technologies necessitates affordable light‐emitting diodes (LEDs) as sources to run photonic devices. A sustainable strategy is demonstrated utilizing a commercial ultravoilet (UV) LED source to power flexible crystal waveguides of (Z)‐3‐(3′,5′‐bis(trifluoromethyl)‐[1,1′‐biphenyl]‐4‐yl)‐2‐(4‐methoxyphenyl) acrylonitrile (CF3OMe), 9,10‐bis(phenylethynyl)anthracene (BPEA), and 2,2′‐((1E,1′E)‐hydrazine‐1,2‐diylidenebis(methaneylylidene))diphenol (SAA), transducing their respective blue, orange, and yellow fluorescence signals. The focused LED's capability includes i) exciting extremely bent crystal waveguides, ii) evanescently exciting SAA waveguide via energy transfer from a CF3OMe waveguide, and iii) selectively exciting and splitting various signals using a 2 × 2 hybrid directional coupler based on SAA‐BPEA crystals. These demonstrations underscore the practicality of the proposed technique for sustainable applications in photonic systems related to VLC. [ABSTRACT FROM AUTHOR]

1,4,5,8-tetrasubstituted dihyroanthracene-based triptycene trisquinones (TT) molecules, THAO-TT and tris(THAO)-TT, were synthesized by Diels–Alder reaction between TT and 1,4,5,8-tetrakis(hexyloxy)anthracene to produce the extended triptycene derivatives containing electron-accepting functionality. The prepared THOA-TT and tris(THOA)-TT exhibited excellent thermal stability owing to the rigid TT framework. The optical and redox properties of THOA-TT and tris(THOA)-TT were controlled by the homoconjugation between the benzoquinone units and the peripheral units through the connecting methine groups. [ABSTRACT FROM AUTHOR]

Series of mixed-ligand coordination polymers (CP) and metal–organic frameworks (MOFs) based on bulky 9,10-di(1H-imidazol-1-yl)anthracene (dia) were synthesized from aqueous solutions even with very short (<10 min) reaction times. Two different metals (M = Cu, Ni) and three different secondary ligands were used to generate six new structures: [Cu2(dia)2(5-aip)2]·6H2O (1), [Ni2(dia)2(5-aip)2]·5H2O (2), [Cu2(dia)2(2-ata)2]·4H2O (3), [Ni(dia)(2-ata)·Ni(dia)2(2-ata)]·2.5H2O (4), [Cu8(dia)2(5-sip)4(OH)4] (5) and [Ni3(dia)5(5-sip)2]·6DMF·14H2O (6). Structure analyses involving single-crystal X-ray diffraction (SCXRD), powder X-ray diffraction (PXRD) and Fourier-transform infrared spectroscopy (FT-IR) were conducted along with studies determining the thermal stabilities and optical properties of the compounds. The results indicate that the developed fast and green syntheses can produce pure CP and MOF phases that have various thermally stable and visible light absorbing structures which may find applications in photocatalysis. [ABSTRACT FROM AUTHOR]

Thermally activated delayed fluorescence (TADF) is an emission mechanism whereby both singlet and triplet excitons can be harvested to produce light. Significant attention is devoted to developing TADF materials for organic light‐emitting diodes (OLEDs), while their use in other organic electronics applications such as sensors, has lagged. A family of TADF emitters, TPAPyAP, TPAPyBP, and TPAPyBPN containing a triphenylamine (TPA) donor and differing nitrogen‐containing heterocyclic pyrazine‐based acceptors is developed and systematically studied. Depending on the acceptor strength, these three compounds emit with photoluminescence maxima (λPL), of 516, 550, and 575 nm in toluene. Notably, all three compounds show a strong and selective spectral response to the presence of ZnCl2, making them the first optical TADF sensors for this analyte. It is demonstrated that these three emitters can be used in vacuum‐deposited OLEDs, which show moderate efficiencies. Of note, the device with TPAPyBPN in 2,8‐bis(diphenyl‐phoshporyl)‐dibenzo[b,d]thiophene (PPT) host emits at 657 nm and shows a maximum external quantum efficiency (EQEmax) of 12.5%. This electroluminescence is significantly red‐shifted yet shows comparable efficiency compared to a device fabricated in 4,4′‐bis(N‐carbazolyl)‐1,1′‐biphenyl (CBP) host (λEL = 596 nm, EQEmax = 13.6%). [ABSTRACT FROM AUTHOR]

In the current field of photopharmacology, molecular photoswitches are applied whose interactions with DNA can be triggered or controlled by light. And although several photochromic reactions have been shown to serve this purpose well, the reversible photocycloaddition and photocycloreversion reactions have been largely neglected. This absence of research is surprising because especially the photodimerization of a DNA ligand leads to products with significant change of the size and shape which, in turn, leads to strongly diminished or even suppressed DNA association. Therefore, photocycloaddition–cycloreversion sequences have a huge potential for the photoinduced, reversible deactivation and activation of ligand–DNA interactions, as will be shown with selected examples in this Concept Article. Specifically, heterostyryl and ‐stilbene derivatives are presented whose DNA–binding properties are efficiently switched in reversible [2+2] photocycloaddition reactions. In addition, the photocontrolled DNA–binding of anthracene derivatives and their heterocyclic benzo[b]quinolizinium analogues in a [4+4] photocycloaddition, as well as the use of this reaction as part of dual–mode switches in combination with redox‐active functionalities, are highlighted. Furthermore, examples of conjugates are provided, in which the photochromic unit is bound covalently to nucleic acids or proteins, such that the photocycloaddition reaction can be used for reversible photoinduced crosslinking, ligation, or inhibition of gene expression. [ABSTRACT FROM AUTHOR]

4,16‐para‐substituted [2.2]paracylophanes with naphthalene (PCP‐NAP), anthracene (PCP‐ANTH), and tetraphenylethylene (PCP‐TPE), as new through‐space conjugated dimers, were prepared by the Suzuki‐Miyaura cross‐coupling reaction of 4,16‐diboryl[2.2]paracyclophane and the corresponding bromo derivative using Pd(PPh3)4 as a catalyst and KOH as a base. The synthesized compounds were fully characterized by NMR and HR‐MS, and their photophysical and electrochemical properties were studied. The photoluminescence quantum yield of PCP‐NAP, PCP‐ANTH were determined to be 0.21, 0.50, and for PCP‐TPE in aggregated state 0.31, respectively. PCP‐TPE exhibited aggregation‐induced emission characteristics when the water fraction was greater than 50 % in THF/water mixtures. PCP‐ANTH and PCP‐TPE were also characterized by X‐ray crystallography, PCP‐ANTH crystallizes in centrosymmetric monoclinic space group C2/c and PCP‐TPE crystallizes in the centrosymmetric triclinic space group P‐1 with one molecule residing at the inversion center. The observed properties of these π‐stacked dimers were compared with respect to through‐space conjugation and conjugation length in the structure. [ABSTRACT FROM AUTHOR]

Flexible organic light‐emitting devices (OLEDs) are emerging as a cutting‐edge technology that revolutionizes displays and lighting panels to be lightweight, bendable, foldable, and even stretchable. However, they suffer from the poor light outcoupling efficiency due to the presence of various optical losses. Herein, a novel method of optical manipulation is proposed, which involves incorporating light‐scattering titanium oxide (TiO2) nanoparticles (NPs) into flexible substrates, along with imprinting random micro‐lens arrays (RMLA) at the bottom of the substrates. Adopting the light outcoupling structures, the flexible single white OLEDs demonstrate a substantial improvement of 95.6% in the external quantum efficiency (EQE) compared to conventional flexible OLEDs, while maintaining a desirable spectral profile without any distortion. To further improve the optoelectronic performance, the light outcoupling structures are adopted in flexible tandem white OLEDs with two emission units, the maximum current efficiency is 147.8 cd A−1, and the maximum EQE comes to 46.2%, which is 1.74 times higher than that of the flexible single OLEDs with the same light outcoupling structures. This work offers a convenient way to design flexible light extraction substrates for efficient wearable electronics. [ABSTRACT FROM AUTHOR]

Using palladium-catalyzed arylation of (S)-2,2′-diamino-1,1′-binaphthalene (BINAM) with the halogen derivatives of naphthalene, anthracene, and anthraquinone, the corresponding N,N′-diaryl derivatives were synthesized. The dependence of the yields of the compounds on the structure of the initial halogen derivatives was shown. The synthesized compounds were studied in fluorescent enantioselective detection of amino alcohols. The synthesized derivatives demonstrate a response in the case of complex formation with some amino alcohols, but the response is most pronounced for the derivative with anthraquinone substituents. This detector can recognize enantiomers of leucinol, 2-phenylglycinol, and prolinol by different changes in the fluorescence enhancement in the presence of opposite optical isomers. In the case of 2-amino-1-propanol, fluorescence enhancement is observed only in the presence of the (S)-isomer. [ABSTRACT FROM AUTHOR]

We designed and successfully synthesized a novel anthracene-based host material, 10-(4-(naphthalen-1-yl)phenyl)-9-(naphthalen-3-yl)anthracene (2-NaAn-1-PNa). The 2-NaAn-1-PNa exhibited a PL max at 440 nm in film state and demonstrated a wide band gap of 2.95 eV, indicating its suitability as a blue host material. In an OLED device using 2-NaAn-1-PNa as the host and 3Me-1Bu-TPPDA as the dopant, real blue emission was achieved with an electroluminescence maximum (ELmax) at 460 nm and Commission Internationale de L'Eclairage coordinates of (0.133, 0.141). The device exhibited excellent EL characteristics, with an external quantum efficiency of 8.3% and a current efficiency of 9.3 cd/A at 10 mA/cm2. Furthermore, the efficiency roll-off was limited to only 1.9% up to 4000 nits, demonstrating exceptional performance. [ABSTRACT FROM AUTHOR]

14,14′‐Bidibenzo[a,j]anthracenes (BDBAs) were prepared by iridium‐catalyzed annulation of 5,5′‐biterphenylene with alkynes. The molecular geometries of overcrowded BDBAs were verified by X‐ray crystallography. The two dibenzo[a,j]anthryl moieties are connected through the sterically hindered 14 positions, resulting in highly distorted molecular halves. The conformation with a small twist angle between two molecular halves can minimize steric conflicts between the substituents at 1 and 13 positions and the carbon atoms of the central axis, as well as steric clashes between those substituents. One such example is octafluoro‐substituted BDBA, where the interplanar angle between two anthryl moieties is approximately 31° (currently the lowest reported value, cf. 81° in 9,9′‐bianthracene). The intramolecular interactions and electronic couplings between two molecular halves resulted in upfield 1H NMR signals, redshifted absorption and emission bands, and a reduced HOMO–LUMO gap. Photodynamic investigations on BDBAs indicated that the formation of the conventional symmetry‐breaking charge transfer (SBCT) state was suspended by restricted rocking around the central C−C bond. Such a mechanism associated with this highly constrained conformation was examined for the first time. [ABSTRACT FROM AUTHOR]

Organic light-emitting diodes (OLEDs) offer the advantage of flexibility; however, the use of traditional transparent anode ITO limits further extension of their flexible characteristics. In this study, we propose employing an polymer polybenzodifuranedione (PBFDO) as a flexible transparent anode instead of the rigid ITO. To address the issue encountered during the PBFDO solution spin-coating process, we introduced n-butanol into the PBFDO conductive solution to reduce its viscosity and freezing point by modulating intermolecular hydrogen bonding interactions. Consequently, high-quality PBFDO films with high conductivity, superior transmittance, and low surface roughness were successfully obtained via spin-coating. Moreover, due to its proper work function, regular molecular stacking, and low refractive index properties, PBFDO electrode facilitate efficient carrier injection and transport as well as photon extraction. The resulting device utilizing a PBFDO anode combined with Super Yellow as the light-emitting layer exhibited excellent performance characteristics including a normal threshold voltage of 2.6 V and a maximum luminous efficiency of 12.8 cd A−1 comparable to that device based on the ITO electrode. Furthermore, flexible device also achieved satisfactory performance (7.7 cd A−1) when using the PEN substrate. [ABSTRACT FROM AUTHOR]

Decreasing perovskite nanocrystal size increases radiative recombination due to the quantum confinement effect, but also increases the Auger recombination rate which leads to carrier imbalance in the emitting layers of electroluminescent devices. Here, we overcome this trade‐off by increasing the exciton effective mass without affecting the size, which is realized through the trace Cd2+ doping of formamidinium lead bromide perovskite nanocrystals. We observe an ~2.7 times increase in the exciton binding energy benefiting from a slight distortion of the [BX6]4− octahedra caused by doping in the case of that the Auger recombination rate is almost unchanged. As a result, bright color‐saturated green emitting perovskite nanocrystals with a photoluminescence quantum yield of 96 % are obtained. Cd2+ doping also shifts up the energy levels of the nanocrystals, relative to the Fermi level so that heavily n‐doped emitters convert into only slightly n‐doped ones; this boosts the charge injection efficiency of the corresponding light‐emitting diodes. The light‐emitting devices based on those nanocrystals reached a high external quantum efficiency of 29.4 % corresponding to a current efficiency of 123 cd A−1, and showed dramatically improved device lifetime, with a narrow bandwidth of 22 nm and Commission Internationale de I'Eclairage coordinates of (0.20, 0.76) for color‐saturated green emission for the electroluminescence peak centered at 534 nm, thus being fully compliant with the latest standard for wide color gamut displays. [ABSTRACT FROM AUTHOR]

The solvothermal reaction of Ln(NO3)3•6H2O (Ln = Nd, Sm, Eu, Tb, and Dy) with 9,10-bis(4-carboxylatopyridinium-1-methylene)anthracene dibromide (H2L)Br2 resulted in the formation of an isostructural series of lanthanide-based metal organic frameworks (Ln-MOFs), {[Nd(L)3/2(H2O)2]·(NO3)3·(S)}n (1), {[Sm(L)3/2(H2O)2]·(NO3)3·(S)}n (2), {[Eu(L)3/2(H2O)2]·(NO3)3·(S)}n (3), {[Tb(L)3/2(H2O)2]·(NO3)3·(S)}n (4) and {[Dy(L)3/2(H2O)2]·(NO3)3·(S)}n (5), where S denotes squeezed disordered solvent molecules and out of three nitrate ions in the voids, one nitrate is squeezed due to the high disorder. These MOFs were characterized with various techniques and single crystal X-ray analysis revealed a three dimensional (3D) (4,4,6)-connected metal organic framework with mononuclear metallic nodes in bicapped trigonal prismatic geometry. From the present series, we selected {[Sm(L)3/2(H2O)2]·(NO3)3·(S)}n (2) as a representative example for structural description and gas adsorption study whereas {[Dy(L)3/2(H2O)2]·(NO3)3·(S)}n (5) was used for the sensing of nitro compounds. All MOFs showed stability up to 200 °C. 2 demonstrates a higher CO2 uptake, despite exhibiting a low specific surface area (SABET) in N2 sorption studies. The sensing result shows that 5 act as selective sensors towards TNP with quenching efficiency greater than 99%. [ABSTRACT FROM AUTHOR]

In this study, it is considered three anthracene derivatives, characterized meticulously in terms of their chemical structure and product purity. Extensive quantum chemical calculations are conducted to elucidate their optical and nonlinear optical properties, shedding light on the mechanism of photoinduced conformational transformation, a pivotal discovery in this research. Experimental analyses encompassed fundamental optical properties and advanced nonlinear optical phenomena, including z‐scan experiments, second harmonic generation (SHG), and third harmonic generation (THG). Remarkably, a groundbreaking all‐optical switching phenomenon in these materials is experimentally validated, marking a significant advancement and contributing to their potential applications. [ABSTRACT FROM AUTHOR]

There has been much progress on mononuclear chromium(III) complexes featuring luminescence and photoredox activity, but dinuclear chromium(III) complexes have remained underexplored in these contexts until now. We identified a tridentate chelate ligand able to accommodate both meridional and facial coordination of chromium(III), to either access a mono‐ or a dinuclear chromium(III) complex depending on reaction conditions. This chelate ligand causes tetragonally distorted primary coordination spheres around chromium(III) in both complexes, entailing comparatively short excited‐state lifetimes in the range of 400 to 800 ns in solution at room temperature and making photoluminescence essentially oxygen insensitive. The two chromium(III) ions in the dimer experience ferromagnetic exchange interactions that result in a high spin (S=3) ground state with a coupling constant of +9.3 cm−1. Photoinduced energy transfer from the luminescent ferromagnetically coupled dimer to an anthracene derivative results in sensitized triplet‐triplet annihilation upconversion. Based on these proof‐of‐principle studies, dinuclear chromium(III) complexes seem attractive for the development of fundamentally new types of photophysics and photochemistry enabled by magnetic exchange interactions. [ABSTRACT FROM AUTHOR]

Charge injection and transport layers with optimum carrier transport properties are essential for stable and efficient organic light-emitting diode (OLED) devices. Herein, we report two tetraphenylethylene-diphenylamine derivatives, TPOMe and TPOSt having four and two methoxy substituents, respectively, and explore their potential as solution-processable hole injection layers (HILs) for OLEDs. Standard, Alq3-based green OLEDs with a simple device design were used to demonstrate the properties of the synthesized HILs, in comparison with a commercially available standard HIL, m-MTDATA. TPOMe-based device exhibited a current efficiency of 4.2 cd A−1, while TPOSt-based device showed 3.81 cd A−1 at 10 mA cm−2. Both the above devices showed better performance compared to a control device fabricated with the standard HIL, m-MTDATA, which showed a relatively lower current efficiency value (1.70 cd A−1 at 10 mA cm−2). Similarly, the maximum external quantum efficiency (EQE) of TPOMe (1.77%) and TPOSt (1.55%) were higher than that of the m-MTDATA-based device (1.40%). Although m-MTDATA device has better luminance and hole mobility compared to TPOMe and TPOSt devices, the optimum charge balance in the latter devices leads to better current efficiency and EQE. [ABSTRACT FROM AUTHOR]

The anthracene biodegradation potential of Serratia quinivorans HP5 was studied under a controlled laboratory environment. The green TiO2 nanoparticles (NPs) synthesized from Paenibacillus sp. HD1PAH was used to accelerate the biodegradation process. The synergistic application of TiO2 NPs and S. quinivorans HP5 resulted in a reduction of anthracene concentration by 1.2 folds in liquid‐medium and 1.5 folds in contaminated soil. Gas‐chromatography and mass‐spectrometric investigation showed the production of four anthracene derivatives, namely 1,2‐anthracene dihydrodiol, 6,7‐benzocoumarin, anthrone, and 9,10‐anthraquinoneat the termination of experimental periods. Furthermore, bacterial biomass increased by 23.3 folds in the presence of TiO2 NPs, and overall soil enzyme activities were enhanced by 4.2 folds in the treated samples. In addition, there was a negative correlation observed between the biomass of S. quinivorans HP5 and the concentrations of anthracene, suggesting the involvement of bacterium in anthracene biodegradation processes. The degradation pathway of anthracene revealed its transformation into the less toxic compound 9,10‐anthraquinone. Overall, this study elucidates a novel biodegradation pathway for anthracene and highlights the potential of nano‐assisted bacterial remediation as a promising approach for environmental cleanup. [ABSTRACT FROM AUTHOR]

In the efforts to generate a less toxic X‐Ray bioimaging contrast agent, a fully organic, radioluminescent nanoparticle system that emits in the near‐infrared (NIR) region when excited with an X‐Ray source is synthesized using a two‐step process. First, red‐emitting nanoparticles are fabricated by the emulsion copolymerization of styrene and propargyl acrylate with anthracene, naphthalimide, and rhodamine B methyl methacrylate derivatives. Subsequently, the nanoparticles are modified with silicon phthalocyanine and indocyanine green derivatives via a copper(I)‐catalyzed azide/alkyne cycloaddition "click" reaction. By coupling an organic scintillator with four Förster resonance energy transfer‐pairing dyes, X‐Ray‐induced, multiple, sequential energy transfer is exploited to convert ionizing radiation from an X‐Ray source into NIR light, which is optimal for biomedical imaging. Proof‐of‐concept imaging studies show that the X‐Ray‐induced indocyanine green fluorescence from the particulate system can be visualized through porcine tissue. Additionally, toxicity studies in human embryonic kidney cells indicate that the particles are nontoxic and applicable in vivo. [ABSTRACT FROM AUTHOR]

It is vital to develop highly efficient non‐doped blue organic light‐emitting diodes (OLEDs) with high color purity and low‐efficiency roll‐off for applications in display and lighting. Herein, two blue D‐A fluorophores TPA‐PO and TPA‐DPO are designed and synthesized, in which phenanthro[9,10‐d]oxazole (PO) acts as the acceptor and triphenylamine as the donor. TPA‐PO and TPA‐DPO display good thermal stability and efficient luminescence efficiency in neat film. Results based on photophysical property and theoretical calculation demonstrate that TPA‐PO and TPA‐DPO possess the hybridized local and charge‐transfer (HLCT) feature, which can utilize the triplet exciton to achieve highly efficient electroluminance (EL). The non‐doped OLEDs with TPA‐PO/TPA‐DPO as pure emissive layer show the uniform EL emission peak at 468 nm, corresponding to CIE coordinates of (0.168, 0.187) and (0.167, 0.167), respectively. The TPA‐DPO‐based non‐doped OLEDs provide the maximum external quantum efficiency (EQE) of 7.99 % and high exciton utility efficiency of 48.4 %~72.6 %. Moreover, the TPA‐DPO‐based device exhibits low‐efficiency roll‐off, still maintaining the EQE of 6.03 % at the high luminance of 5000 cd m−2. Those findings state clearly that PO is a promising building block of blue fluorophore with a potential HLCT feature to be applied in non‐doped OLEDs. [ABSTRACT FROM AUTHOR]

Photocatalysis through energy transfer has been investigated for the facilitation of [4 + 2] cycloaddition reactions. However, the high reactivity of radical species poses a challenging obstacle to achieving enantiocontrol with chiral catalysts, as no enantioselective examples have been reported thus far. Here, we present the development of catalytic asymmetric [4 + 2] dearomative photocycloaddition involving anthracene and its derivatives with alkenylazaarenes. This accomplishment is achieved by utilizing a cooperative photosensitizer and chiral Brønsted acid catalysis platform. Importantly, this process enables the activation of anthracene substrates through energy transfer from triplet DPZ, thereby initiating a precise and stereoselective sequential transformation. The significance of our work is highlighted by the synthesis of a diverse range of pharmaceutical valuable cycloadducts incorporating attractive azaarenes, all obtained with high yields, ees, and drs. The broad substrate scope is further underscored by successful construction of all-carbon quaternary stereocenters and diverse adjacent stereocenters. While significant progress has been made in classical Diels-Alder reactions, the use of simple and inert feedstock chemicals under mild reaction conditions still remains challenging. Here the authors present the development of catalytic asymmetric [4 + 2] dearomative photocycloaddition involving anthracene and its derivatives with alkenylazaarenes. [ABSTRACT FROM AUTHOR]

In a series of earlier studies, the effect of benzo‐annelation was found to be a useful tool for tuning the aromaticity in polycyclic conjugated compounds to desired level. In this work we studied the (anti)aromaticity of benzo‐annelated derivatives of three conjugated hydrocarbons (anthracene, fluoranthene and biphenylene) in their lowest lying singlet (S0) and triplet (T1) states by means of the energy effect (ef), harmonic oscillator model of aromaticity (HOMA), multicentre delocalization indices (MCI), magnetically induced current densities (MICDs) and nucleus independent chemical shifts (NICS). We showed that benzo‐annelation is a topology‐based effect which can be used to modify the T1 state excitation energies (E(T1)). A quantitative model was established being able to accurately predict the E(T1) based only on the numbers of angularly, linearly and geminally annelated benzene rings. In addition, it was demonstrated that the E(T1) can be directly related to the (anti)aromatic character of the central ring in the studied molecules in their S0 state. [ABSTRACT FROM AUTHOR]

Robust solid-core silica particles with submicrometer size and anthracene-containing mesoporous shell were obtained and studied as model water-dispersable photoreactors. An anthracene derivative containing a triethoxysilyl group was synthesized and co-condensed with tetraethoxysilane in various ratios to form a photoactive mesoporous shell with a thickness up to approximately 80 nm on previously prepared solid silica particles. Mesopores of as-synthesized particles, without a commonly applied removal of the micellar templates, offered a confined space for solubilization of hydrophobic molecules. Efficient excitation energy transfer from anthracene chromophores to both hydrophobic (perylene) and hydrophilic (fluoresceine) encapsulated acceptors was observed in an aqueous dispersion of the particles. Photosensitized oxidation of encapsulated perylene was shown to proceed efficiently in such systems serving as water-dispersable photoreactors. Importantly, the designed core–shell systems were found to be stable for a long time (at least 24 months) and robust enough, thanks to the presence of solid cores, to be handled by centrifugation in aqueous dispersions. All these features make them promising candidates for reusable systems for the photosensitized degradation of water pollutants, especially hydrophobic pollutants. [ABSTRACT FROM AUTHOR]

The problem of plastic waste in the environment calls for the development of new polymeric materials designed specifically for easy recycling at the end of their life cycle. Herein, a green polymer system comprising a series of necklace‐shaped polydimethylsiloxanes bearing anthracene dimer units is developed. The polymers have low environmental impact and are easily recycled. Further, their flexibility and glass transition temperatures are easy to control. These necklace‐shaped inorganic polymers are synthesized by photopolymerizing (dimerizing) anthracene‐terminated oligo‐dimethylsiloxane monomers. A key achievement of the present work is the successful chemical recovery of the monomers from the polymers through thermal depolymerization, enabling monomer–polymer recycling. By applying equilibrium polymerization with base catalysts, monomers with a controlled distributed chain length are synthesized from monomers with a constant chain length. The necklace‐shaped polymers synthesized from these randomized monomers have amorphous structures and readily form transparent films. It is possible to modulate the thermal and mechanical properties of the polymers by controlling the average chain length of the polydimethylsiloxane between the anthracene dimers. This investigation presents a method for the synthesis and cyclic utilization of polymer materials with a wide range of applications, including plastics and elastomers. [ABSTRACT FROM AUTHOR]

In the field of silicon photonics, highly compact and miniature high‐density circuits are achieved by precisely shaping millimeter‐long waveguides into spiral configurations. Organic photonics, on the other hand, takes advantage of mechanically flexible crystal spiral waveguides (SWs) within organic photonic circuits. These SWs offer versatility, enabling precise control over light paths and mechanical programmability. This study introduces an innovative pick‐and‐place technique for constructing various organic spiral waveguides (OSWs) with different geometries, such as Cornu, Archimedean, elliptical, rectangular, four‐sided polygons, and three‐sided polygons. Additionally, this method allows for the creation of optically reprogrammable photonic circuits. Custom‐synthesized flexible crystals are used, including blue‐emitting (Z)−3‐(4‐(9H‐carbazol‐9‐yl)phenyl)−2‐(3,5‐bis(trifluoromethyl)phenyl)acrylonitrile (Cz‐2CF3), green‐emitting (E)−1‐(((5‐bromopyridin‐2‐yl)imino)methyl)naphthalene‐2‐ol (BPyIN), cyan‐emitting 9,10‐dibromo anthracene (DBA), and red‐emitting 4,7‐bis(4‐octylthiophen‐2‐yl)benzo[c][1,2,5]thiadiazole (BTD). Systematically integrating a Cz‐2CF3 OSW (with two ports for optical signal routing in clockwise/counterclockwise directions) with DBA and BTD waveguides produces multi‐color hybrid photonic circuits with customizable optical functions, tailored to specific design needs. The number of output ports can be dynamically adjusted through mechanical programming by coupling crystals tip‐to‐tip when replacing the DBA waveguide with a BPyIN waveguide using the pick‐and‐place technology. This mechanically programmable hybrid spiral photonic circuit seamlessly operates across the entire visible spectral bandwidth, making it valuable for various applications, including high‐fidelity sensing, spectrometer components, and intelligent circuitry. [ABSTRACT FROM AUTHOR]

A triazole-bridged anthracene-sugar derivative 1 was designed and synthesized in one step. The sensing ability of 1 towards picric acid over other nitroaromatic compounds was established by absorbance and fluorescence spectroscopy in a water−acetonitrile medium (3 : 2, v/v). Furthermore, compound 1 could recognize Au(III) ions in 100% water among different metal species and anions. In the presence of picric acid, the receptor's fluorescence quenches within a minute. The Stern–Volmer quenching constants for picric acid and Au(III) ions were observed to be 1.59 × 105 and 1.8 × 105 M–1, respectively. Spectroscopic studies and density functional theory calculations supported the formation of the non-emissive charge transfer complex 1-picric acid after the interaction between 1 and picric acid. The probe showed a 1 : 1 binding mode for picric acid and Au(III) ions. The detection limits of 1 for picric acid and Au(III) were calculated to be 0.09 and 0.094 µM, respectively. Furthermore, receptor 1 has been effectively utilized to sense picric acid in river, pond, and tap water samples. Interestingly, it was found that the quenching process of 1 with picric acid is totally opposite to quenching with Au(III). [ABSTRACT FROM AUTHOR]

Two blue-emitting materials, 4-(12-([1,1′:3′,1″-terphenyl]-5′-yl)chrysen-6-yl)-N,N-diphenylaniline (TPA-C-TP) and 6-([1,1′:3′,1″-terphenyl]-5′-yl)-12-(4-(1,2,2-triphenylvinyl)phenyl)chrysene (TPE-C-TP), were prepared with the composition of a chrysene core moiety and terphenyl (TP), triphenyl amine (TPA), and tetraphenylethylene (TPE) moieties as side groups. The maximum photoluminescence (PL) emission wavelengths of TPA-C-TP and TPE-C-TP were 435 and 369 nm in the solution state and 444 and 471 nm in the film state. TPA-C-TP effectively prevented intermolecular packing through the introduction of TPA, a bulky aromatic amine group, and it showed an excellent photoluminescence quantum yield (PLQY) of 86% in the film state. TPE-C-TP exhibited aggregation-induced emission; the PLQY increased dramatically from 0.1% to 78% from the solution state to the film state. The two synthesized materials had excellent thermal stability, with a high decomposition temperature exceeding 460 °C. The two compounds were used as emitting layers in a non-doped device. The TPA-C-TP device achieved excellent electroluminescence (EL) performance, with Commission Internationale de L′Eclairage co-ordinates of (0.15, 0.07) and an external quantum efficiency of 4.13%, corresponding to an EL peak wavelength of 439 nm. [ABSTRACT FROM AUTHOR]

Although λ5‐phosphinine derivatives are known as a promising class of blue fluorescent emitters, those photoluminescent quantum yield (PLQY) values have been reached up to 92 %, however, only a few examples have been explored as an emitter for blue organic light‐emitting device (OLED), and the external quantum efficiency (EQE) has been below 2.4 % so far. In this study, we newly developed two types of blue λ5‐phosphinine derivatives namely CN‐COCF3 and CO2Me‐CHO, and investigated the photophysical properties in the solid states. The photophysical analyses in solid state films suggested that the strong electron‐accepting nature of these λ5‐phosphinine derivatives caused the inferior PLQY values, and the exciplex formation with the host and neighboring materials should be avoided to improve the device efficiency. By choosing suitable host and neighboring materials with deep ionization potentials, we successfully realized efficient blue fluorescent OLEDs with EQE of over 4 % and CIE (0.14, 0.18). This is among the best in λ5‐phosphinine‐based blue OLEDs so far. [ABSTRACT FROM AUTHOR]

Herein, we report the unique multiple‐stimuli responsiveness of anthracene‐tethered o‐carborane derivatives. We designed and synthesized anthracene derivatives with different substitution positions and numbers of the o‐carborane units. Two compounds had characteristic crystal structures involving the columnar π‐stacking structures of the anthracene units. From the analysis of crystalline‐state structure–property relationships, it was revealed that the crystals exhibited the photosalient effect accompanied by photochemical [4+4] cycloaddition reactions and temperature‐dependent photophysical dual‐emission properties including excimer emission of anthracene. Those properties were considered as non‐radiative and radiative deactivation pathways through the excimer formation in the excited state and the formation of excimer species was facilitated by the π‐stacking structure of anthracene units. Moreover, we found unusual temperature dependency on the occurrence of the photosalient effect. According to the data from variable temperature X‐ray crystallography, a strong correlation between lattice shrinkage and strain accumulation is suggested. [ABSTRACT FROM AUTHOR]

Over the past few decades, organic light-emitting diodes (OLEDs) find applications in smartphones, televisions, and the automotive sector. However, this technology is still not perfect, and its application for lighting purposes has been slow. For further development of the OLEDs, we designed twisted donor-acceptor-type electroactive bipolar derivatives using benzophenone and bicarbazole as building blocks. Derivatives were synthesized through the reaction of 4-fluorobenzophenone with various mono-alkylated 3,3′-bicarbazoles. We have provided a comprehensive structural characterization of these compounds. The new materials are amorphous and exhibit suitable glass transition temperatures ranging from 57 to 102 °C. They also demonstrate high thermal stability, with decomposition temperatures reaching 400 °C. The developed compounds exhibit elevated photoluminescence quantum yields (PLQY) of up to 75.5% and favourable HOMO-LUMO levels, along with suitable triplet-singlet state energy values. Due to their good solubility and suitable film-forming properties, all the compounds were evaluated as blue TADF emitters dispersed in commercial 4,4′-bis(N-carbazolyl)-1,10-biphenyl (CBP) host material and used for the formation of emissive layer of organic light-emitting diodes (OLEDs) in concentration-dependent experiments. Out of these experiments, the OLED with 15 wt% of the emitting derivative 4-(9′-{2-ethylhexyl}-[3,3′]-bicarbazol-9-yl)benzophenone exhibited superior performance. It attained a maximum brightness of 3581 cd/m2, a current efficacy of 5.7 cd/A, a power efficacy of 4.1 lm/W, and an external quantum efficacy of 2.7%. [ABSTRACT FROM AUTHOR]

Two derivatives of phenyl pyrimidine as acceptor unit and triphenylamino or 4,4′-dimethoxytriphenylamino donor groups were designed and synthesized as emitters for organic light-emitting diodes (OLEDs) aiming to utilize triplet excitons in the electroluminescence. Thermogravimetric analysis revealed high thermal stability of the compounds with 5% weight loss temperatures of 397 and 438 °C. The theoretical estimations and photophysical data show the contributions of local excited and charge transfer states into emission. The addition of the methoxy groups led to the significant improvement of hole-transporting properties and the bathochromic shift of the emission from blue to green-blue spectral diapason. It is shown that mixing of the compounds with the organic host results in facilitation of the delayed emission. The singlet–triplet energy splitting was found to be too big for the thermally activated delayed fluorescence. No thermal activation of the long-lived emission was detected. No experimental evidence for triplet–triplet annihilation and room temperature phosphorescence were detected making the hot exciton mechanism the most probable one. The OLEDs based on the compounds reached the maximum external quantum efficiency of up to 10.6%. [ABSTRACT FROM AUTHOR]

This article explores the synthesis and coordination behavior of 9,10-Diarsatriptycene, a unique molecule with potential applications in various fields. The authors focus on the synthesis of heavy pnictogen-containing DHT analogues using nonvolatile arsenic precursors, which eliminates the need for dangerous reagents. The structures of the synthesized compounds were analyzed, revealing the effects of the bridgehead element. The compounds were found to have different stability and coordination abilities, and one compound formed a supramolecular polymer structure. Further research is being conducted to explore the potential applications of these compounds. [Extracted from the article]

Two new Schiff base compounds of N‐{2‐[(E)‐сyclohexyliminomethyl]phenyl}‐4‐methylbenzenesulfonamide, N‐{2‐[(E)‐(4‐сyclohexylphenyl)iminomethyl]phenyl}‐4‐methylbenzenesulfonamide and their Zn(II) complexes have been synthesized and characterized by elemental analysis, FT‐IR and UV–Vis spectra, and single crystal X‐ray determination. In both complexes, Zn2+ ions have a tetrahedral environment with two nitrogen atoms of the tosylamide groups and two nitrogen atoms of the imine fragment. Time‐dependent density functional theory calculations have been performed on two zinc(II) complexes in order to assign their experimental UV–visible absorption bands. Zinc(II) complexes showed thermal stability up to 335–340°C under a nitrogen atmosphere by thermogravimetric analysis (TGA). The photoluminescent spectra show that both Zn(II) complexes in the solid state at room temperature emit blue luminescence with high emission quantum yields of 20% and 29%. The doped devices with configurations of indium tin oxide (ITO)/poly(3,4‐ethylenedioxythiophene):poly(styrene sulfonate) (PEDOT:PSS)/N,N′‐Di(1‐naphthyl)‐N,N′‐diphenyl‐(1,1′‐biphenyl)‐4,4′‐diamine (NPD)/4,4′‐N,N′ ‐dicarbazolebiphenyl (CBP):Zinc(II) complex (5%)/1,3,5‐tris(N‐phenylbenzimidazole‐2‐yl) benzene (TPBI)/LiF/Al have been fabricated and investigated. The doped device based on the complex with the сyclohexylphenyl substituent of the ligand showed the best electroluminescent characteristics with maximum brightness Lmax of 3415 cd/m2, maximum current efficiency of 2.8 cd/A, and power efficiency of 1.9 lm/W, while the doped device with emitter on the base of the complex with the сyclohexyl substituent showed slightly worse electroluminescence (EL) performance with Lmax of 2105 cd/m2, maximum current efficiency of 2.1 cd/A, and power efficiency of 1.6 lm/W. [ABSTRACT FROM AUTHOR]

We control the anisotropic molecular packing of vapor-deposited glasses of ABH113, a deuterated anthracene derivative with promise for future organic light emitting diode materials, by changing the deposition rate and substrate temperature at which they are prepared. We find that at substrate temperatures from 0.65 Tg to 0.92 Tg, the deposition rate significantly modifies the orientational order in the vapor-deposited glasses as characterized by x-ray scattering and birefringence. Both measures of anisotropic order can be described by a single deposition rate–substrate temperature superposition (RTS). This supports the applicability of the surface equilibration mechanism and generalizes the RTS principle from previous model systems with liquid crystalline order to non-mesogenic organic semiconductors. We find that vapor-deposited glasses of ABH113 have significantly enhanced density and thermal stability compared to their counterparts prepared by liquid-cooling. For organic semiconductors, the results of this study provide an efficient guide for using the deposition rate to prepare stable glasses with controlled molecular packing. [ABSTRACT FROM AUTHOR]

Three bis‐anthracene (BA) compounds, characterized by varying alkyl chain lengths between the two anthracene groups, were synthesized and investigated using 3He NMR spectroscopy on He@C60 derivatives. The Diels‐Alder reaction of these BAs with fullerene was comprehensively explored. Findings disclosed that BAs with shorter linkers formed mono‐adducts with 3He@C60 at lower concentrations. Conversely, the BA compound with the longest linker (1 c) yielded both mono‐adducts and bis‐para‐adducts with C60, marked by a distinct 3He NMR signal peak for bis‐adducts at −12.84 ppm. Importantly, the versatility of the 3He@C60 probe was exemplified in characterizing intricate fullerene reactions that conventionally pose challenges. Theoretical analyses validated reaction products, with computational models substantiating experimental results. [ABSTRACT FROM AUTHOR]

Enantio‐ and diastereoselective dearomative [4+2]‐cycloaddition reaction between N,N‐dimethylhydrazone derived from 9‐anthracenecarboxaldehyde and α,β‐unsaturated aldehydes is reported. The developed strategy utilizes HOMO‐rising activation of diene (via hydrazone formation) and aminocatalytic LUMO‐lowering activation of dienophile (via iminium ion formation). High chemical and stereochemical efficiency have been obtained owing to the application of Jørgensen catalyst. Target cycloadducts were subjected to selected transformations aiming at unmasking the hydrazone moiety that proceeded with preservation of optical purity introduced in the organocatalytic step. [ABSTRACT FROM AUTHOR]

In this work, we synthesized and characterized four bipolar host materials, which were 9-(naphthalen-1-yl)-10-(4-(naphthalen-2-yl)phenyl)anthracene (NA-AN-NA), 1-(4-(10-(naphthalen-1-yl)anthracen-9-yl)phenyl)dibenzo[b,d]furan, 1-(4-(10-phenylanthracen-9-yl)phenyl)dibenzo[b,d]furan, and 2-(4-(10-phenylanthracen-9-yl)phenyl)dibenzo[b,d]furan. These four materials possessed good thermal stability and showed suitable highest occupied molecular orbital and lowest unoccupied molecular orbital energy levels that match the hole and electron transporting layers. Organic light-emitting diodes (OLEDs) were fabricated based on these four hosts and 4,9-diisopropyl-N,N,N′,N′-tetrakis-(4-methyl-biphenyl-3-yl)-pyrene-1,6-diamine (DITBDAP) as a guest in the emitting layer. The OLED based on NA-AN-NA achieved a deep-blue emission centered at 460 nm with the Commission International de L'Eclairage coordinates of (0.1298, 0.1712) and reached a maximum external quantum efficiency of 8.10% and a maximum luminance of 7973 cd m−2. The full width at half maximum of the NA-AN-NA-based OLED was 42 nm. And the current efficiency maintained at 8.71 cd A−1 at 1000 cd m−2, with a low efficiency roll-off of only 2.9%. The results indicate that the strategy of designing a host with balanced hole and electron transporting properties is a practical way to achieve highly efficient and low roll-off deep blue OLEDs. [ABSTRACT FROM AUTHOR]

Two new structural isomers of pyreno[4,5‐d]imidazole‐triazatruxene (C‐Pyl‐TAT and N‐Pyl‐TAT) were successfully synthesized via microwave‐assisted Suzuki cross‐coupling reaction. The target compounds were characterized by 1H‐NMR, 13C‐NMR and MALDI‐TOF mass spectroscopy. These compounds emitted blue fluorescence signals with maxima wavelengths around 434 and 436 nm in toluene solution. They exhibited good film‐forming properties and thermal stabilities with glass‐transition temperature (Tg) and decomposition temperature (T5d) above 128 °C and 390 °C, respectively. The solution‐processed Alq3‐based devices with the structure of ITO/PEDOT:PSS/HTL/Alq3/LiF:Al were fabricated to evaluate the hole‐transporting properties of these compounds. The performance of the device with C‐Pyl‐TAT as a hole‐transporting layer (HTL) showed a low turn‐on voltage of 2.8 V, a high external quantum efficiency of 1.07 %, and a maximum luminance of 19,770 cd m−2. Moreover, the use of spin‐casted films of 1,3‐bis(N‐carbazolyl)benzene doped with C‐Pyl‐TAT or N‐Pyl‐TAT as blue‐emitting materials in OLED devices were also demonstrated. [ABSTRACT FROM AUTHOR]

The development of adhesives with excellent reversibility is necessary for the removal, recycling and reusing of precision components under specific conditions in electronics manufacturing. The integration of photosensitive cycloaddition reactions into common adhesive systems is a viable alternative for reversible modification. In this contribution, a novel reversible acrylate adhesive was successfully prepared by doping thiol-functionalized anthracene derivatives in situ, and its characteristic structure, photophysical properties and mechanical performance were systematically evaluated. As expected, the reversible dimers structure of anthracene provides remarkable bonding and debonding properties for adhesives. Sample #3 achieved an excellent shear strength of 1.67 ± 0.07 MPa and 91% debonding rate, with 283.03% and 89.58% improvement over the control sample #0 without anthracene modification, respectively. Furthermore, the shear strength and debonding rate for secondary bonding were up to 2.37 ± 0.07 MPa and 82%. We believe that our paradigm can provide a feasible approach for reversible adhesive design. [ABSTRACT FROM AUTHOR]

It is well known that triplet–triplet annihilation upconversion (TTU) can enhance electroluminescence (EL) efficiency by converting two low‐energy triplet excitons into one high‐energy singlet exciton. However, conventional intermolecular TTU requires high doping concentration to activate, limiting device architecture. Here, six dimer molecules comprised of two anthracene units connected by a spacer unit are investigated, which have a possibility of the intramolecular TTU process. As a result, two dimer molecules show high TTU efficiencies close to the theoretical maximum even in dispersed, diluted conditions. By comparing these molecular conformations, a correlation is found between the dimer structures of two anthracene units and the TTU activity in the diluted condition, i.e., the 3D molecular structure with the exciton utilizing efficiency. [ABSTRACT FROM AUTHOR]

A hydrocarbon‐soluble barium anthracene complex was prepared by means of metal vapour synthesis. Reaction of 9,10‐bis(trimethylsilyl)anthracene (Anth′′) with barium vapour gave deep purple Ba(Anth′′) which after extraction with diethyl ether crystallised as the cyclic octamer [Ba(Anth′′)⋅Et2O]8. Dissolution in benzene or toluene led to replacement of the Et2O ligand with a softer arene ligand and isolation of Ba(Anth′′)⋅arene. Diffusion ordered spectroscopy (DOSY NMR) measurements in benzene‐d6 indicate solution species with a molecular weight that equals a trimeric constitution. Natural population analysis (NPA) assigned charges of +1.70 and −1.70 to Ba and Anth′′, respectively, relating to highly ionic Ba2+/Anth′′2− bonding. Preliminary reactivity studies with air, Ph2C=NPh, or H2 show that the complex reacts as a Ba0 synthon by release of neutral Anth′′. This soluble molecular Ba0/BaII redox synthon provides new routes for the syntheses of barium complexes under mild conditions. [ABSTRACT FROM AUTHOR]

The photooxidative stability of a series of doubly bridged anthracenes was evaluated after their preparation via twofold macrocyclization of a bis(resorcinyl)anthracene. Lightfastness correlates with the energy levels of the highest occupied molecular orbital (HOMO), resulting in superior stability of the tetraesters compared to the tetraethers. The lengths and steric demand of the linker only plays a minor role for the ester‐based compounds, which can be prepared in reasonable yields and thus tested in proof‐of‐concept organic light‐emitting diodes. Double ester‐bridging allows deep blue electro‐luminescence, highlighting the importance of the choice of the functional groups used for macrocyclization. [ABSTRACT FROM AUTHOR]

The 1,8-Diazaanthracene-2,9,10-triones, their 5,8-dihydro derivatives, and 1,8-diazaanthracene-2,7,9,10-tetraones, structurally related to the diazaquinomycin family of natural products, were synthesized in a regioselective fashion employing Diels–Alder strategies. These libraries were studied for their cytotoxicity in a variety of human cancer cell lines in order to establish structure–activity relationships. From the results obtained, we conclude that some representatives of the 1,8-diazaanthracene-2,9,10-trione framework show potent and selective cytotoxicity against solid tumors. Similar findings were made for the related 1-azaanthracene-2,9,10-trione derivatives, structurally similar to the marcanine natural products, which showed improved activity over their natural counterparts. An enantioselective protocol based on the use of a SAMP-related chiral auxiliary derived was developed for the case of chiral 5-substituted 1,8-diazaanthracene-2,9,10-triones, and showed that their cytotoxicity was not enantiospecific. [ABSTRACT FROM AUTHOR]