共查询到20条相似文献,搜索用时 23 毫秒
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Hiroyuki Nishide Naoki Yoshioka Takahiko Kaku Takashi Kaneko Masanori Yamazaki Eishun Tsuchida 《高分子科学杂志,A辑:纯化学与应用化学》2013,50(11-12):1177-1187
Synthesis and magnetic properties of π-conjugated stable polyradicals bearing a polyacetylene backbone are described. 2,6-Di-tert-butyl-4-ethynylphenol (8) and 4-ethynylphenylhydrogalvinoxyl (9) are polymerized with W, Mo chloride or Rh complex to yield their polyacetylene derivatives with molecular weight of ca. 104, while 2-ethynylphenalenone (10) gives only its oligomer. The polymers are soluble in common solvents and converted to the corresponding conjugated polyradicals via heterogeneous chemical oxidation using PbO2 or alkaline K3Fe(CN)6. The polyradicals with extremely high spin concentration (up to 4.8 × 1023 spins/monomer mol) are obtained by regulating the oxidative conditions. The polyradicals are quite stable in solution and even in the solid state because of resonance stabilization and/or a steric effect of the substituents. Magnetic interactions between the unpaired spins in the conjugated stable polyradicals are discussed. 相似文献
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Dr. Jong Min Lim Dr. Mei‐Jin Lin Dr. Ivo Krummenacher Prof. Dr. Holger Braunschweig Prof. Dr. Dongho Kim Prof. Dr. Frank Würthner 《Angewandte Chemie (International ed. in English)》2015,54(47):13980-13984
Unprecedented neutral perylene‐3,4:9,10‐tetracarboxylic acid bisimide (PBI) radicals and biradicals were synthesized by facile chemical oxidation of 4‐hydroxyaryl‐substituted PBIs. Subsequent characterization by optical and magnetic spectroscopic techniques, as well as quantum chemical calculations, revealed an open‐shell singlet biradical ground state for the PBI biradical OS ‐ 2.. (〈s2〉=1.2191) with a relatively small singlet–triplet energy gap of 0.041 eV and a large singlet biradical character of y=0.72. 相似文献
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Sergio A. Guilln‐Castellanos J. Scott Parent Ralph A. Whitney 《Journal of polymer science. Part A, Polymer chemistry》2006,44(2):983-992
Variations of the Williamson ether synthesis were employed to prepare a range of new derivatives of brominated poly(isobutylene‐co‐isoprene) (BIIR). Unambiguous characterization of the polymeric products was accomplished by spectroscopic comparisons to low‐molecular‐weight analogues derived from brominated 2,2,4,8,8‐pentamethyl‐4‐nonene, which served as a model for the reactive functionality found within BIIR. The substitution of bromide from BIIR occurred at moderate temperatures with stoichiometric amounts of quaternary ammonium phenoxide to yield O‐alkylation products in high yields. Simple mixtures of BIIR, KOH, and aliphatic alcohols generated the desired allylic ethers when heated above 110 °C in the absence of quaternary ammonium salts. Knowledge gained from these small‐molecule alkylations was used to prepare graft copolymers from BIIR and poly(ethylene oxide) through the exploitation of the apparent ability of polyethers to activate potassium alkoxides in nucleophilic substitutions. © 2005 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 44: 983–992, 2006 相似文献
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以4,5-二(2'-氰乙基硫基)-1,3-二硫杂环戊烯-2-硫酮为原料经甲醇钠消除一个氰乙基生成4-(2'-氰乙基硫基)-1,3-二硫杂环戊烯-2-硫酮的单钠盐, 生成的单钠盐再与1,4-二(氯甲基)苯反应生成4,4'-二(2-氰乙基硫基)-5,5'-(1,4-二亚甲基苯)-二(1,3-二硫杂环戊烯-2-硫酮). 接着在乙酸汞的作用下生成4,4'-二(2-氰乙基硫基)-5,5'-(1,4-二亚甲基苯)-二(1,3-二硫杂环戊烯-2-酮), 此化合物在亚磷酸三乙酯的作用下发生偶联反应, 生成由TTF单元和苯单元构建的新型四硫富瓦烯环蕃和另一种四硫富瓦烯衍生物. 并分别通过循环伏安法和化学氧化法对它们及其导电复合物的电化学性质和紫外光谱进行了研究. 还研究了这种新型四硫富瓦烯环蕃在金纳米颗粒表面自组装行为. 相似文献
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通过双Suzuki偶联反应一步合成了2种含硫甲基的芴-苯结构化合物2,7-二(4-硫甲基苯基)-9,9-二己基-芴(a)和2,7-二(2,6-二甲基-4-硫甲基苯基)-9,9-二己基-芴(b).紫外-可见和荧光光谱以及分子轨道理论计算表明,位阻较小的化合物a具有更好的共轭性能,其最大紫外-可见吸收波长达到351nm,比两端苯基含4个邻位取代基的化合物b红移了38nm;化合物a的最大荧光发射波长达到410nm,为典型的蓝光化合物,比化合物b红移了43nm.化合物a和b都具有较高的荧光量子产率,分别为59%和65%,在光电材料方面具有潜在的应用前景. 相似文献