63139-21-9Relevant articles and documents
Photoredox-Catalyzed Simultaneous Olefin Hydrogenation and Alcohol Oxidation over Crystalline Porous Polymeric Carbon Nitride
Qiu, Chuntian,Sun, Yangyang,Xu, Yangsen,Zhang, Bing,Zhang, Xu,Yu, Lei,Su, Chenliang
, p. 3344 - 3350 (2021/07/26)
Booming of photocatalytic water splitting technology (PWST) opens a new avenue for the sustainable synthesis of high-value-added hydrogenated and oxidized fine chemicals, in which the design of efficient semiconductors for the in-situ and synergistic utilization of photogenerated redox centers are key roles. Herein, a porous polymeric carbon nitride (PPCN) with a crystalline backbone was constructed for visible light-induced photocatalytic hydrogen generation by photoexcited electrons, followed by in-situ utilization for olefin hydrogenation. Simultaneously, various alcohols were selectively transformed to valuable aldehydes or ketones by photoexcited holes. The porosity of PPCN provided it with a large surface area and a short transfer path for photogenerated carriers from the bulk to the surface, and the crystalline structure facilitated photogenerated charge transfer and separation, thus enhancing the overall photocatalytic performance. High reactivity and selectivity, good functionality tolerance, and broad reaction scope were achieved by this concerted photocatalysis system. The results contribute to the development of highly efficient semiconductor photocatalysts and synergistic redox reaction systems based on PWST for high-value-added fine chemical production.
end alkene multi-fluorine diaryl acetylene liquid crystal compound and its preparation method
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Paragraph 0030, (2017/02/23)
The invention relates to an alkene-terminated polyfluorinated diaryl acetylene liquid crystal compound and a synthesis method thereof. The compound is shown in the structural formula I as shown in the specification, wherein in the structural formula I, (F)m and (F)n both refer to fluorine atom substitutes; m and n refer to the substitute number of fluorine atoms, and the value thereof is 0-2; x refers to the number of connected methylene, and the value thereof is 0-3; and R refers to C1-C15 alkyls, C1-C15 alkenyls, C1-C15 alkoxy and C1-C15 enyloxy. According to the invention, because the compound is synthesized through adopting classic reactions such as nucleophilic substitution, coupling reaction, and the like, the operation is simple, and the yield and purity of products are high; and the compound has the advantages of large negative dielectric anisotropy, low melting point, wide liquid crystal phase interval, large double refraction, and the like, and can be applied to a dual-frequency liquid crystal display mode.
A recyclable Au(I) catalyst for selective homocoupling of arylboronic acids: Significant enhancement of nano-surface binding for stability and catalytic activity
Zhang, Xin,Zhao, Haitao,Wang, Jianhui
experimental part, p. 5153 - 5160 (2011/12/15)
Au nanoparticles stabilized by polystyrene-co-polymethacrylic acid microspheres (PS-co-PMAA) were prepared and characterized via X-ray diffraction (XRD), and transmission electron microscope (TEM). The Au nanoparticles supported on the microspheres showed highly selective catalytic activity for homo-coupling reactions of arylboronic acids in a system of aryl-halides and arylboronic acids. X-ray photoelectron spectroscopy (XPS) spectra of the catalyst shows large amounts of Au(l) complexes band to the surface of the Au nanoparticles, which contributes to the selective homocoupling of the arylboronic acids. More importantly, this supported Au complex is a highly recyclable catalyst. The supported Au catalyst can be recycled and reused at least 6 times for a phenylboronic acid reactant, whereas the parent complex shows very low catalytic activity for this compound. The high catalytic activity of this material is attributed to: (1) the high surface to volume ratio which leads to more active sites being exposed to reactants; (2) the strong surface binding of the Au nanoparticle to the Au(1) complexes, which enhances both the stability and the catalytic activity of these complexes. Copyright
