2674-34-2Relevant articles and documents
Synthesis and characterization of low-birefringent crosslinkable fluorinated poly(arylene ether sulfide)s containing pendant phenyl moiety
Lee, Kwan-Soo,Kim, Jae-Pil,Lee, Jae-Suk
, p. 632 - 638 (2010)
Fluorinated poly(arylene ether sulfide) (FPAESI) and ethynyl-terminated fluorinated poly(arylene ether sulfide) (E-FPAESI) were synthesized via step-growth polymerization from prepared dihydroxy monomer and pentafluorophenylsulfide, then E-FPAESI was foll
NON-LINEAR CHROMOPHORE, PHOTOREFRACTIVE COMPOSITE COMPRISING THE SAME AND PHOTOREFRACTIVE DEVICE
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Paragraph 0084-0087, (2021/02/05)
The present invention relates to a non-linear optical dye, to a photorefractive composite comprising the same, and to a photorefractive device and, more specifically, to a non-linear optical dye with improved response speed to an applied electric field by controlling a molecular structure, to a photorefractive composite comprising the same, and to a photorefractive device. The non-linear optical dye according to the present invention has an alkyl group or an alkoxy group having 1 to 10 carbon atoms.
Compound containing fused heterocycle structure, application of compound and organic electroluminescent device
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Paragraph 0139-0141; 0145-0147, (2021/05/05)
The invention relates to the field of organic electroluminescent devices, and discloses a compound containing a fused heterocycle structure, an application of the compound and an organic electroluminescent device. The compound has the general formula structure shown in the formula (I); the compound has a high glass transition temperature, a high decomposition temperature and a high refractive index; and when the compound is applied to a covering layer on a device, the light extraction efficiency of the cathode can be improved, so that the luminous efficiency of the device is improved, and the service life of the device is prolonged.
Screening metal-free photocatalysts from isomorphic covalent organic frameworks for the C-3 functionalization of indoles
Chen, Xiong,Feng, Xiao,Han, Songjie,Li, Chunzhi,Li, He,Li, Ziping,Liu, Xiaoming,Shao, Pengpeng,Xia, Hong
supporting information, p. 8706 - 8715 (2020/05/16)
The visible-light-driven organic transformation using two-dimensional covalent organic frameworks (2D-COFs) as metal-free heterogeneous photocatalysts is a green and sustainable approach, and it has gained a surge of interest by virtue of the photosensitizer's high crystallinity, abundant porosity, outstanding stability, excellent light-harvesting ability and tunable structure. However, the guiding principle for designing, constructing and selecting COF-based photocatalysts has not been put forward so far. Herein, we contribute a fascinating strategy to guide the acquisition of excellent framework photocatalysts, which is to screen them from a series of isomorphic COFs. As a proof of concept, three new isomorphic pyrene-based 2D-COFs (COF-JLU23, COF-JLU24 and COF-JLU25) with variable linkers were successfully synthesized. In addition to having similar crystallinity and porosity with the same pore size and shape, their absorption, emission, bandgap, energy level, transient photocurrent response and photocatalytic activity could be easily adjustedviaconfiguring different linkers in frameworks. Indeed, COF-JLU24 with electron donor-acceptor characteristics exhibited the best photocatalytic activity among the three isomorphic COFs for C-3 functionalization reactions of indoles, even better than that of the metal-free photocatalyst g-C3N4. More importantly, the screened COF-JLU24 as a metal-free photocatalyst still displayed extensive substrate adaptability and excellent recyclability. We anticipate that this strategy will become a robust rule of thumb for fast access to COF-based photocatalysts. In addition, we still highlight that the present study broadens the applied frontier of COF-based photocatalysts.
Synthesis of a triethylene glycol-capped benzo[1,2-c:4,5-c']bis[2]benzopyran-5,12-dione: A highly soluble dilactone-bridged p-terphenyl with a crankshaft architecture
Dressler, Justin J.,Charlesworth-Seiler, Eva M.,Dahl, Bart J.
, (2020/10/02)
3,10-Bis(triethylene glycol)benzo[1,2-c:4,5-c']bis[2]benzopyran-5,12-dione has been synthesized as an example of a dilactone-bridged p-terphenyl with a C2h crankshaft architecture that exhibits significant fluorescence. Lactone-bridged rotation
Synergistic Effect of Covalent Bonding and Physical Encapsulation of Sulfur in the Pores of a Microporous COF to Improve Cycling Performance in Li-S Batteries
Royuela, Sergio,Almarza, Joaquín,Manche?o, María J.,Pérez-Flores, Juan C.,Michel, Enrique G.,Ramos, María M.,Zamora, Félix,Ocón, Pilar,Segura, José L.
supporting information, p. 12394 - 12404 (2019/09/06)
Lithium-sulfur batteries stands out as a promising technology for energy storage owing to a combination of favorable characteristics including a high theoretical gravimetric capacity, energy density, inexpensive character, and environmental benignity. Covalent organic frameworks (COFs) are a rapidly developing family of functional nanostructures which combine porosity and crystallinity, and which have been already used in these kinds of batteries to build sulfur electrodes, by embedding sulfur into porous COFs in order to enhance cycle lifetimes. In this contribution, this is taken one step forward and a COF endowed with vinyl groups is used, in order to graft sulfur to the COF skeleton through inverse vulcanization. The main aim of the article is to show the synergistic effect of covalent bonding and physical encapsulation of sulfur in the pores of the COF in order to alleviate the fatal redox shuttling process, to improve the cycling performance, and to provide faster ion diffusion pathways. In addition, it is shown how the material with covalently-bound S provides better electrochemical performance under demanding and/or changeable charge conditions than a parent analogue material with sulfur physically confined, but without covalent linkage.
Bromine formation in solid NaBr/KNO3 mixture and assay of this reaction via bromination of activated aromatics
Rahu, Ida,Keki?ev, Ott,J?rv, Jaak,Burk, Peeter
, p. 2893 - 2898 (2018/08/23)
Bromine formation in the mixture of solid NaBr and KNO3 was observed and the process was studied in different acidified organic solvent–water mixtures by monitoring the bromination of acetanilide and other compounds, containing activated aromatic substituents. This assay is based on fast bromination reaction of these aromatic compounds, as differently from the assay of Br2, the brominated aromatics can be easily determined by conventional gas chromatography–mass spectrometry (GC–MS) methods. It was found that bromine was generated autocatalytically on the surface of salt crystals and the reaction was characterized by a lag period, the duration of which depended on reaction conditions, and importantly on the type of the organic solvent in the reaction mixture. As the bromine formation could be easily controlled by reaction conditions, it was suggested that the studied reaction might have practical applications as an environmentally friendly and economically feasible bromination method. It was also shown that the bromination of aromatics followed the mechanism of classical electrophilic aromatic substitution reaction.
Covalent organic frameworks: Efficient, metal-free, heterogeneous organocatalysts for chemical fixation of CO2 under mild conditions
Zhi, Yongfeng,Shao, Pengpeng,Feng, Xiao,Xia, Hong,Zhang, Yumin,Shi, Zhan,Mu, Ying,Liu, Xiaoming
supporting information, p. 374 - 382 (2018/01/12)
The cycloaddition of CO2 to epoxides to form cyclic carbonates is very promising and does not generate any side products. Metal-free, heterogeneous organocatalysts offer an environmentally friendly alternative to traditional metal-based catalysts. Herein two triazine-based covalent organic frameworks (COF-JLU6 and COF-JLU7) were successfully synthesized under solvothermal conditions. The structural and chemical properties of COFs were fully characterized by using powder X-ray diffraction analysis, structural simulation, Fourier transform infrared spectroscopy, 13C solid-state NMR spectroscopy, electron microscopy, thermogravimetric analysis and nitrogen adsorption. The two COF materials combine mesopores, high crystallinity and good stability, as well as a large number of hydroxy groups in the pore walls. They possess a high Brunauer-Emmett-Teller (BET) specific surface area up to 1390 m2 g-1 and a large pore volume of 1.78 cm3 g-1. The COF-JLU7 displays a high CO2 uptake of 151 mg g-1 at 273 K and 1 bar. Importantly, COF-JLU7 was found to be a highly effective catalyst to convert CO2 into cyclic carbonate through the cycloaddition reaction with epoxides under mild conditions. The effect of reaction parameters, such as reaction temperature, reaction time and CO2 pressure, on the catalytic performance was also investigated in detail. Moreover, the new framework-based catalyst can be recovered and reused five times without a significant loss of catalytic efficiency.
Stack the Bowls: Tailoring the Electronic Structure of Corannulene-Integrated Crystalline Materials
Rice, Allison M.,Dolgopolova, Ekaterina A.,Yarbrough, Brandon J.,Leith, Gabrielle A.,Martin, Corey R.,Stephenson, Kenneth S.,Heugh, Rebecca A.,Brandt, Amy J.,Chen, Donna A.,Karakalos, Stavros G.,Smith, Mark D.,Hatzell, Kelsey B.,Pellechia, Perry J.,Garashchuk, Sophya,Shustova, Natalia B.
supporting information, p. 11310 - 11315 (2018/08/11)
We report the first examples of purely organic donor–acceptor materials with integrated π-bowls (πBs) that combine not only crystallinity and high surface areas but also exhibit tunable electronic properties, resulting in a four-orders-of-magnitude conductivity enhancement in comparison with the parent framework. In addition to the first report of alkyne–azide cycloaddition utilized for corannulene immobilization in the solid state, we also probed the charge transfer rate within the Marcus theory as a function of mutual πB orientation for the first time, as well as shed light on the density of states near the Fermi edge. These studies could foreshadow new avenues for πB utilization for the development of optoelectronic devices or a route for highly efficient porous electrodes.
Covalent organic frameworks as metal-free heterogeneous photocatalysts for organic transformations
Zhi, Yongfeng,Li, Ziping,Feng, Xiao,Xia, Hong,Zhang, Yumin,Shi, Zhan,Mu, Ying,Liu, Xiaoming
supporting information, p. 22933 - 22938 (2017/11/22)
Two-dimensional covalent organic frameworks (2D-COFs) are excellent candidates for photocatalytic organic transformations due to their periodic columnar π-arrays and ordered nanochannels. Here, we present a novel 2D-COF that features permanent porosity wi
