Near-Infrared Electroluminescence beyond 800 nm with High Efficiency and Radiance from Anthracene Cored Emitters

Derivatives based on anthryleno[1,2-b]pyrazine-2,3-dicarbonitrile (DCPA) are used as luminescent materials, to realize near-infrared (NIR) electroluminescence. By functionalizing DCPA with aromatic amine donors, two emitters named DCPA-TPA and DCPA-BBPA are designed and synthesized. Both molecules have large dipole moments owing to the strong intramolecular charge transfer interactions between the amine donors and the DCPA acceptor. Thus, compared with doped films, the emission of neat films of DCPA-TPA and DCPA-BBPA can fully fall into the NIR region (>700 nm) with increasing surrounding polarity by increasing doping ratio. Moreover, the non-doped devices based on DCPA-TPA and DCPA-BBPA provide NIR emission with peaks at 838 and 916 nm, respectively. A maximum radiance of 20707 mW Sr⁻¹ m⁻² was realized for the further optimized device based on DCPA-TPA. This work provides a simple and efficient strategy of molecular design for developing NIR emitting materials.     

Efficient and Saturated Red Light-Emitting Electrochemical Cells Based on Cationic Iridium(III) Complexes with EQE up to 9.4 %

Solid-state light-emitting electrochemical cells (LECs) have several advantages, such as low-voltage operation, compatibility with inert metal electrodes, large-area flexible substrates, and simple solution-processable device architectures. However, most of the studies on saturated red LECs show low or moderate device efficiencies (external quantum efficiency (EQE) <3.3 %). In this work, we demonstrate a series of five red-emitting cationic iridium complexes ( RED1- - RED5 ) with 2,2′-biquinoline ligands and test their electroluminescence (EL) characteristics in LECs. The Commission Internationale de l′Eclairage (CIE) 1931 coordinates for the LECs based on these complexes are all beyond the National Television System Committee (NTSC) red standard point (0.67, 0.33). The maximal EQE of the neat-film RED1 -based LECs reaches 7.4 %. The reddest complex, RED3 , is doped in the blue-emitting host complex, BG , to fabricate host–guest LECs. The maximal EQE of the host–guest LECs (1 wt % complex RED3 ) reaches 9.4 %, which is among the highest reported for the saturated red LECs.     

Intermediate Filaments in Higher Plant Cells and Their Reconstitution in vitro

Delicate networks of 10-nm filaments were found to exist widely in suspension cells of cultured carrot and root tip cells of pea by selective extraction combined with whole mount and diethylene glycol distearate plastic embedment-free section for electron microscopy. These filament components are polypeptides of 52, 58, 62—64 and 50kD using Western blot analysis. A relatively uniform 10-nm filaments, as well as bundle of such filaments could be reconstituted in vitro. The reconstituted filaments were indistinguishable from native plant intermediate filaments in morphology and protein components. Thus the intermediate filaments are actually present in cytoplasm of higher plants. We also found no obvious specificity in tissues and species by comparison of the proteins among various types of plant cells.     

Synthesis of Glutamic Acid-based Cluster Galactosides and Their Binding Affinities with Liver Cells

Structurally well defined di-, tri- and tetra-valent cluster galactosides were synthesized in a convenient way.Oligo-glutamic acids were assembled as scaffolds. The presence of amine groups in these three ligands is expected to couple with drugs or genes for delivery. The binding affinities of these cluster galactoses to liver cells were determined by in vitro binding studies. Among them, the tetravalent cluster galactose (19) showed the highest affinity to liver cell. It is therefore a promising targeting device for the specific delivery of drugs or genes to parenchymal liver cells.     

Assay of Histamine in Single Mast Cells by Capillary Zone Electrophoresis with Electrochemical Detection

Histamine is one of the chemical mediators in connection with allergies. Only Pihel et al.1 reported a method for detection of histamine in isolated mast cells by high- performance liquid chromatography with electrochemical detection. In this method, single cells were removed and transferred to 300-nL microvials. A part of the supernatant from individual vials was injected into the chromatography column. The analysis of histamine in individual rat peritoneal mast cells using CZE with amp…     

Cerium Alkoxides—Synthesis, Properties and Their Use in Michael Addition Reaction

Cerium(III) alkoxides served as an effective and attractive promoter for the Michael addition reaction with excellent chemical yields under mild conditions in short reaction time.     

Electrochemical Detection of Alkaline Phosphatase in BALB／c Mouse Fetal Liver Stromal Cells with Capillary Electrophoresis

A method for determination of alkaline phosphatase (ALP) in BALB/c mouse fetal liver stromal cells has been described based on the catalytic reaction. After the cell extract is incubated with the substrate disodium phenyl phosphate, the reaction product phenol generated by ALP is determined by capillary electrophoresis with electrochemical detection.     

On the Conformation of Dimeric Acceptors and Their Polymer Solar Cells with Efficiency over 18 %

The determination of molecular conformations of oligomeric acceptors (OAs) and their impact on molecular packing are crucial for understanding the photovoltaic performance of their resulting polymer solar cells (PSCs) but have not been well studied yet. Herein, we synthesized two dimeric acceptor materials, DIBP3F-Se and DIBP3F-S, which bridged two segments of Y6-derivatives by selenophene and thiophene, respectively. Theoretical simulation and experimental 1D and 2D NMR spectroscopic studies prove that both dimers exhibit O-shaped conformations other than S- or U-shaped counter-ones. Notably, this O-shaped conformation is likely governed by a distinctive “conformational lock” mechanism, arising from the intensified intramolecular π–π interactions among their two terminal groups within the dimers. PSCs based on DIBP3F-Se deliver a maximum efficiency of 18.09 %, outperforming DIBP3F-S-based cells (16.11 %) and ranking among the highest efficiencies for OA-based PSCs. This work demonstrates a facile method to obtain OA conformations and highlights the potential of dimeric acceptors for high-performance PSCs.     

Synthesis of β-Ketoiminato Copper(II) Complexes and Their Use in Copper Deposition

The template synthesis of ethylenediamine ( 1 ) with 2-acetylcyclopentanone ( 2 ) and [Cu(OAc)₂ · H₂O] ( 5 ) produced [Cu(1-(2-cC₅H₆(O))C(Me)NCH₂)₂)] ( 6 ) in 82 % yield. Reaction of 5 with bis(benzoylacetone)diethylenetriamine ( 7 , = L H)^[1] gave [Cu(μ-OAc)( L )(H₂O)]₂ ( 8 ). The solid-state structures of 6 and 8 were determined confirming that 8 possesses intra- and intermolecular hydrogen bonds resulting in a dimer formation. The thermal behavior of 6 – 8 was studied by TG and TG-MS. Under oxygen CuO was formed, whereas under Ar Cu/Cu₂O ( 6 ) or Cu ( 8 ) was obtained. Complex 6 was used as CVD precursor for Cu and Cu-oxide deposition (substrate temp., 400–500 °C, N₂, 60 mL · min^–1; O₂, 60 mL · min^–1; pressure, 0.87–1.5 mbar). The as-obtained deposits show separated particles of different appearance at the substrate surface as evidenced by SEM. Non-volatile 8 was applied as spin-coating precursor for Cu and CuO formation [conc. 0.25 mol · L^–1; volume 0.2 mL; 3000 rpm; depos. time 2 min; heating rate 50 K · min^–1; holding time 60 min (Ar), 120 min (air) at 800 °C]. The samples on silicon consist of granulated particles (Ar) or are non-dense with a grainy topography (air). EDX and XPS measurements confirmed the formation of Cu (Ar) or CuO (O₂) with up to 13 mol-% C impurity.     

γ-Hydroxyacetylenic Acid Derivatives: Generation from Propiolic Acid and Ester Anions and Their Use in Butenolide Synthesis

γ-Hydroxyacetylenic acids and esters have been found to be conveniently prepared in our laboratory by the addition of the propiolic acid dianion¹ or the acetylide of methylpropiolate² to an aldehyde or to a ketone (Scheme I, Table I). These polyfunctional compounds have been shown previously to be useful synthetic intermediates in route to such compounds as 1,3-dienes,² carbohydrates³ and butenolides.^4–7     

α,β-Acetylenic Acids and Their Derivatives in Reactions with Hydrogen Sulfide and Thiols

Results of the research into reactions of ,-acetylenic acids and their derivatives with hydrogen sulfide and thiols are summarized. The addition direction and stereochemistry depend on whether there is an activating group at the triple bond, as well as on the structure of the thiol. The reactions not infrequently provide not only monothiylation products, but complete with intramolecular cyclization yielding polyfunctional heterocyclic compounds.     

Reaction of Imidazole Anions with Difluorodiiodomethane and Their Products Conversion in Sulfinatodehalogenation System

Treatment of difluorodiiodomethane with N-sodium salts of imi-dazoles at -15 ℃ gave N-difluoroiodomethylated imidazoles (3) in good yields. The addition of 3 to alkyne or alkenes initi-ated by sodium dithionate at room temperature resulted in the corresponding adducts in high yields.     

Polyethylenimine—Poly(vinyl Chloride) Crosslinked Polymers and Their Use in Adsorption of Mercuric and Cupric Salts

The alkylation reaction of polyethylenimine (PEI) by polyvinyl chloride) (PVC) was investigated. PEI-PVC cross-linked polymers with high PEI content were obtained in good yields. Study of the adsorption by complexation of mercuric chloride and cupric sulfate from aqueous solution by these polymers showed that they can be used effectively to remove mercuric and cupric salts from aqueous solutions.     

Monitoring Homovanillic Acid and Vanillylmandelic Acid in Human Urine by Capillary Electrophoresis with Electrochemical Detection

A simple,rapid and low-cost method of separation and determination of homovanillic acid and vanillylmandelic acid in human urine was developed based on capillary zone electrophoresis/amperometric detection with high sensitivity and good resolution.     

Synthesis of Some Novel α-Cyanoketene-N,S-acetals Derived from Secondary Aliphatic Amines and Their Use in Pyrazole Synthesis

New α-cyanoketene-N,S-acetals 2(a–g) and β-dialkylamine-α-cyanoacrylates 3(g–i) were synthesized in good to excellent yields by the reaction of ethyl 2-cyano-3,3-bis(methylthio)acrylate 1 with secondary aliphatic amines (i.e., N-methylalkyl- and N-ethylalkylamines), and pyrrolidine, in the presence of triethylamine, under reflux in ethanol, for 1–16 h, depending on the amine used. Five N-methylalkyl amines and pyrrolidine yielded exclusively mono-substituted N,S-acetals 2(a–f) in good yields. On the other hand, N-ethylbenzylamine gave a mixture of monosubstituted products including N,S-acetal 2g in 35% yield and the unexpected product ethyl 3-[benzyl(ethyl)amino]-2-cyanoacrylate 3g in 50% yield. N-Ethylcyclohexylamine and N-ethylbutylamine did not produce N,S-acetals and gave only the unexpected products ethyl 2-cyano-3-[cyclohexyl(ethyl)amino]acrylate 3h and ethyl 3-[butyl(ethyl)amino]-2-cyanoacrylate 3i in good yields. The α-cyanoketene-N,S-acetals 2(a–f), 2j, and 2k underwent cyclization with the binucleophile hydrazine in ethanol under reflux to afford substituted pyrazoles 4(a–f), 4j, and 4k in good yields.

[Supplementary materials are available for this article. Go to the publisher's online edition of Synthetic Communications® for the following free supplemental resources: Full experimental and spectral details.]     

Sub-10 nm Aggregation-Induced Emission Quantum Dots Assembled by Microfluidics for Enhanced Tumor Targeting and Reduced Retention in the Liver

A robust platform is developed to assemble sub-10 nm organic aggregation-induced emission (AIE) particles using four different AIE luminogens (AIEgens) with emissions from green to the second near-infrared window (NIR-II). They are called AIE quantum dots (QDs) to distinguish from typical AIE dots which are larger than 25 nm. Compared with AIE dots that are larger than 25 nm, AIE QDs allow more efficient cellular uptake and imaging without surface modification of any membrane-penetrating peptides or other targeting molecules. NIR-II AIEgens, which have nearly no background fluorescence from organisms, are used to demonstrate that AIE QDs can achieve high contrast at the tumor as small as 80 mm³ and evade the liver more efficiently than AIE dots. AIE QDs hold a good promise for sensitive and precise diagnosis of the latent solid tumor in clinical medicine with much lower off-targeting to the liver than AIE dots.     

Electrochemical Determination of Epinephrine with a Pyrolytic Graphite Electrode in the Presence of Ascorbic Acid and Dopamine

Epinephrine (EP) is one of the most important neurotransmitters in mammalian central nervous systems, existing in the nervous tissue and body fluid in the form of large organic cations, and controlling the nervous system in the series of biological perfor…     

A Highly Water-Soluble Aggregation-Induced Emission Luminogen with Anion-π+ Interactions for Targeted NIR Imaging of Cancer Cells and Type I Photodynamic Therapy

The low oxygen dependence of type I photosensitizers (PSs) has made them a popular choice for treating solid tumors. However, the drawbacks of poor water solubility, short emission wavelength, poor stability, and inability to distinguish cancer cells from normal cells limit the application of most type I PSs in clinical therapy. Thereby, developing novel type I PSs for overcoming these problems is an urgent but challenging task. Herein, by utilizing the distinctive structural characteristics of anion-π⁺ interactions, a highly water-soluble type I PS (DPBC-Br) with aggregation-induced emission (AIE) characteristic and near-infrared (NIR) emission is fabricated for the first time. DPBC-Br displays remarkable water solubility (7.3 mM) and outstanding photobleaching resistance, enabling efficient and precise differentiation between tumor cells and normal cells in a wash-free and long-term tracking manner via NIR-I imaging. Additionally, the superior type I reactive oxygen species (ROS) produced by DPBC-Br provide both specific killing of cancer cells in vitro and inhibition of tumor growth in vivo, with negligible systemic toxicity. This study rationally constructs a highly water-soluble type I PS, which has higher reliability and controllability compared with conventional nanoparticle formulating procedures, offering great potential for clinical cancer treatment.