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81.
Kenjiro Onimura Mieko Matsushima Munetoshi Nakamura Tatsuya Tominaga Kazuhiro Yamabuki Tsutomu Oishi 《Journal of polymer science. Part A, Polymer chemistry》2011,49(16):3550-3558
2,3‐Diaryl substituted maleimides as model compounds of conjugated maleimide polymers [poly(RMI‐alt‐Ar) and poly(RMI‐co‐Ar)] were synthesized from 2,3‐dibromo‐N‐substituted maleimide (DBrRMI) [R= cyclohexyl (DBrCHMI) and n‐hexyl (DBrHMI)] and aryl boronic acid using palladium catalysts. To clarify structures of conjugated polymer containing maleimide units at the main chain, 13C NMR spectra of 2‐aryl or 2,3‐diaryl substituted maleimides were compared with those of N‐substituted maleimide polymers. Copolymers obtained with DBrRMI via Suzuki‐Miyaura cross‐coupling polymerizations or Yamamoto coupling polymerizations were dehalogenated structures at the terminal end. This dehalogenation may contribute to the low polymerizability of DBrRMIs. On the other hand, the π‐conjugated compounds showed high solubility in common organic solvents. The N‐substituents of maleimide cannot significantly affect the photoluminescence spectra of 2,3‐diaryl substituted maleimides derivatives. The fluorescence spectra of poly(RMI‐alt‐Ar) and poly(RMI‐co‐Ar) varied with N‐substituents of the maleimide ring. When exposed to ultraviolet light of wavelength 352 nm, a series of 1,4‐phenylene‐ and/or 2,5‐thienylene‐based copolymers containing N‐substituted maleimide derivatives fluoresced in a yellow to blue color. It was found that photoluminescence emissions and electronic state of π‐conjugated maleimide derivatives were controlled by aryl‐ and N‐substituents, and maleimide sequences of copolymers. © 2011 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem, 2011 相似文献
82.
Siraye E. Debebe Desta A. Gedefaw Wendimagegn Mammo Teketel Yohannes Francesca Tinti Alberto Zanelli Valeria Fattori Nadia Camaioni 《Journal of polymer science. Part A, Polymer chemistry》2011,49(12):2693-2699
The synthesis and characterization of a novel polythiophene substituted with a 2′‐pentyloxy‐5′‐(1″′‐oxooctyl) phenyl group (PPOPT) is reported. The bulk transport properties of thin films of PPOPT are investigated by admittance spectroscopy. The dramatic effect of the phenyl side chain on the mobility of positive carriers in films of PPOPT is described. The photophysics of PPOPT in both solution and thin film is also investigated and correlated to substituent‐driven intrachain and interchain arrangements. © 2011 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem, 2011 相似文献
83.
F. David-Quillot A. Duchêne J.-M. Catala A. Balland-Longeau J. Thibonnet 《高分子科学杂志,A辑:纯化学与应用化学》2013,50(5):461-467
Fourteenth group oganometallic styrene derivatives were synthesised by nitroxide-mediated controlled radical polymerization using di-tert butyl nitroxide (A-T) as initiator. This is the first time that nitroxide-controlled radical polymerization has been successfully adapted for the synthesis of new polystyrenes bearing organometallic species with controlled molecular weights and narrow polydispersities. Monomer reactivity ratios were determined in controlled nitroxide-mediated radical copolymerization between styrene and substituted styrene. All experiments permitted the synthesis of new organometallic polymers that will be used for the development of a polymer capsule for Inertial Confinement Fusion Experiments. 相似文献
84.
A new sandwiched polyoxometalate [HK11Cd4Cl2(PW9034)2]·18H2O (1), incor- porating a unique hybrid tetranuclear cadmium cluster (abbreviated to {Cd4}) with two trivacant polyanions [B-α-PW9O34]9-, has been hydrothermally synthesized and structurally characterized by elemental analyses, IR spectroscopy, UV-vis, and single-crystal X-ray diffraction analysis. Crystal data for 1: monoclinic, space group C2/c, a = 19.2997(4), b = 13.8014(3), c = 31.9819(8) A, β = 102.764(2)°, V= 8308.3(3) A3, Z = 4, P2O86Cl2K11Cd4W18H37, Mr = 5735.13, Dc = 4.584 mg-mm-3, F(000) = 10084, μ = 26.579 mm-1, the final R = 0.0378 and wR = 0.0989 for 6558 observed reflections (I〉 2σ(I)). X-ray crystallographic study shows that the molecular structure of 1 contains four cadmium atoms. Two CdO6 distorted octahedra and two CdOsC1 distorted octahedra combine with each other in turn via edge-sharing, resulting in a regular rhomb-like cluster sandwiched between two {B-a-PW9034} units. Further, the sandwich-type polyoxoanions were connected by K+ ions to form a complicated 3-D open-framework through connecting with each terminal O atom of the [Cd4C12(PW9O34)2]12- polyoxoanions. In addition, compound 1 exhibits photoluminescence property at room temperature and the band gap can be assessed at 3.25 eV. 相似文献
85.
Xiaofeng Luo Naiwen Kang Lei Li Jianping Deng Wantai Yang 《Journal of polymer science. Part A, Polymer chemistry》2010,48(7):1661-1668
This article reports a class of nanoscale materials, that is, optically active nanoparticles consisting of helical‐substituted polyacetylenes. Such nanoparticles were prepared via aqueous catalytic miniemulsion polymerization, by which nanoparticles with a wide range of size (diameter: 60–400 nm) can be easily prepared. The nanoparticles could be obtained in quantitative monomer conversions. Large specific rotations and intense circular dichroism effects demonstrated that the nanoparticles possessed large optical activities; moreover, the optical activities were found to increase with a decrease in particle size. From the obtained polymer nanoparticles and with poly(vinyl alcohol) (PVA) as supporting material, composite films were further prepared and also exhibited considerable optical activities. © 2010 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 48: 1661–1668, 2010 相似文献
86.
Condensation of levoglucosenone with the carbanion ofrac-allyl phenyl sulfoxide, in contrast with reactions of this anion with the majority of other unsaturated ketones, proceeds
without regio- or enantioselectivity to give a (1.0–1.8): 1 mixture of products of both 1,2- and 1,4-γ-addition of the allylic
residue. Each product is a (1.2–1.6): 1 mixture of epimers at the asymmetric sulfur atom.
Translated fromIzvestiya Akademii Nauk. Seriya Khimicheskaya, No. 1, pp. 157–159, January, 1999. 相似文献
87.
Silica chloride catalysted one pot cyclocondensation of aldehydes,ethyl acetoacetate and phenyl hydrazine leading to substituted pyrazoles has been reported. 相似文献
88.
Gareth J. Rowlands Author Vitae 《Tetrahedron》2010,66(9):1593-501
89.
Koji Takagi Tsuyoshi Nakagawa Hidenobu Takao 《Journal of polymer science. Part A, Polymer chemistry》2010,48(1):91-98
Two arylenevinylene compounds bearing the cyano group at α‐position ( 6 ) and β‐position ( 9 ) from the dialkoxylphenylene unit were synthesized, in which the molecular termini were functionalized with 3‐bromocarbazole. The Suzuki coupling copolymerization of these compounds with 1,4‐bis[(3′‐bromocarbazole‐9′‐yl)methylene]‐2,5‐didecyloxybenzene and 9,9‐dihexylfluorene‐2,7‐bis(boronic acid) was carried out to obtain copolymers ( cp67 and cp97 ) containing the cyano‐substituted arylenevinylene fluorophore of 7 mol %. Model compounds ( 6 ′ and 9 ′) corresponding to the arylenevinylene fluorophore were also prepared. The UV spectra of copolymers resembled that of homopolymer hp with no arylenevinylene segment in both CHCl3 solution and thin film. The emission maxima of copolymers in CHCl3 (394 nm) agreed with that of homopolymer indicating that the emission bands originated from the carbazole‐fluorene‐carbazole segment. The emission maximum wavelength of copolymer cp67 in thin film (477 nm) indicated fluorescence from the cyano‐substituted arylenevinylene fluorophore because of the occurrence of fluorescence resonance electron transfer. In contrast, copolymer cp97 showed fluorescence at 528 nm to suggest the formation of a new emissive species such as a charge‐transfer complex (exciplex). © 2009 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 48: 91–98, 2010 相似文献
90.
Hamid Goudarziafshar Ahmad Reza Moosavi‐Zare Zahra Jalilian Mehdi Abdolmaleki 《中国化学会会志》2019,66(5):529-534
Nano‐Zn‐[2‐boromophenyl‐salicylaldimine‐methylpyranopyrazole]Cl2 (nano‐[Zn‐2BSMP]Cl2) as a nanoparticle Schiff base complex and a catalyst was introduced for the solvent‐free synthesis of 4‐((2‐hydroxynaphthalen‐1‐yl)(aryl)methyl)‐5‐methyl‐2‐phenyl‐1H‐pyrazol‐3(2H)‐ones by the multicomponent condensation reaction of various aromatic aldehydes, β‐naphthol, ethyl acetoacetate, and phenyl hydrazine at room temperature. 相似文献