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61.
62.
Bian Y Li L Dou J Cheng DY Li R Ma C Ng DK Kobayashi N Jiang J 《Inorganic chemistry》2004,43(23):7539-7544
Three (1,8,15,22-tetrasubstituted phthalocyaninato)lead complexes Pb[Pc(alpha-OR)(4)] [H(2)Pc(alpha-OC(5)H(11))(4) = 1,8,15,22-tetrakis(3-pentyloxy)phthalocyanine; H(2)Pc(alpha-OC(7)H(15))(4) = 1,8,15,22-tetrakis(2,4-dimethyl-3-pentyloxy)phthalocyanine; H(2)Pc(alpha-OC(10)H(7))(4) = 1,8,15,22-tetrakis(2-naphthyloxy)phthalocyanine] (1-3) have been prepared as racemic mixtures by treating the corresponding metal-free phthalocyanines H(2)Pc(alpha-OR)(4) (4-6) with Pb(OAc)(2).3H(2)O in refluxing n-pentanol. The molecular structure of Pb[Pc(alpha-OC(5)H(11))(4)] (1) in the solid state has been determined by single-crystal X-ray diffraction analysis. This compound, having a nonplanar structure, crystallizes in the monoclinic system with a P2(1)/c space group. Each unit cell contains two pairs of enantiomeric molecules, which are linked by weak coordination of the Pb atom of one molecule with an aza nitrogen atom and its neighboring oxygen atom from the alkoxy substituent of another molecule, forming a pseudo-double-decker supramolecular structure in the crystals with a short ring-to-ring separation, 2.726 A, and thus a strong ring-ring pi-pi interaction. The decreased molecular symmetry for these complexes has also been revealed by the NMR spectra of 1 and 2. The methyl protons of the 3-pentyloxy and 2,4-dimethyl-3-pentyloxy side chains of 1 and 2, respectively, are chemically inequivalent. In addition to the elemental analysis and various spectroscopic characterizations, these compounds have also been electrochemically studied. Two one-electron oxidations and up to five one-electron reductions have been revealed by cyclic voltammetry (CV) and differential pulse voltammetry (DPV) methods. 相似文献
63.
64.
After mixing a methylbenzene 4 with “magic blue” solution in F113 (CClF2CCl2F) containing bis{perfluoro[1-(2-fluorosulfonyl)ethoxy]ethyl}nitroxide 2 and perfluoro-1-nitroso-1-[1-(2-fluorosulfonyl)ethoxy]ethane 3 at room temperature, benzylic H-atom of 4 could be selectively abstracted by 2, and benzyl radical 5 thus generated was immediately trapped by 3. Based on hyper-fine splitting constants (hfsc), the structure of the spin adducts perfluoro[1-(2-fluorosulfonyl)ethoxy]ethyl benzyl nitroxides 6 derived from seven methylbenzenes have been identified. The mechanism of the H-abstraction/spin trapping process is also discussed. 相似文献
65.
Zheng-Huan Lin Hong-Yan Dou Jin Li Cheng-Xue Zhao 《Research on Chemical Intermediates》2005,31(9):867-873
The H-abstractions/spin-trapping reactions with primary, secondary and tertiary alcohols of new 'magic blue' reagents, namely,
the blue F113 (CClF2CCl2F) solution containing bis{perfluoro[1-(2-fluorosulfonyl)ethoxy]ethyl} nitroxide (2) and perfluoro[1-nitroso-1-(2-fluorosulfonyl)ethoxy]ethane (3) both generated in the reaction of perfluoro[2-(2-fluorosulfonyl)ethoxy]propionyl peroxide (1) with sodium nitrite in F113 at room temperature, were studied by EPR. Based on the interpretation of the EPR spectra of
the spin adducts, nitroxides, the region-selectivity of H-abstraction has been disclosed and the possible mechanistic paths
of H-abstraction have also been discussed. EPR of H-abstraction by using 'magic blue' reagents can also be used for producing
various hydroxyalkyl radicals from common alcohols. 相似文献
66.
Ke Tao Hongjing Dou Kang Sun 《Colloids and surfaces. A, Physicochemical and engineering aspects》2006,290(1-3):70-76
Dextran-Fe3O4 hybrid clusters were fabricated by coprecipitating ferric and ferrous ions in the presence of dextran, and after characterization of these clusters combined with calculation based on classical nucleation theory, a structure model of these hybrid clusters was proposed. The hybrid cluster was believed including small Fe3O4 nanoparticles and dextran which acted as both nucleating agent and stabilizer, so that exist in both the inside of magnetite nanoparticles and the periphery of the hybrid clusters. Besides, the effects of WCD (weightiron cation:weightdextran) and molecular weight of dextran on the size, morphology and magnetic property of clusters were also investigated in this paper. It was found that the variation of WCD and molecular weight of dextran have great effect on the size of the hybrid clusters, but have almost no effect on the size of the Fe3O4 nanoparticles. The characterization of magnetic property demonstrated that the Fe3O4 nanoparticles are of a single domain and the saturation magnetization was affected by the size of dextran-Fe3O4 hybrid clusters. 相似文献
67.
68.
Yandong Dou Kenry Dr. Jiang Liu Jianze Jiang Prof. Qing Zhu 《Chemistry (Weinheim an der Bergstrasse, Germany)》2019,25(28):6896-6901
o-Alkenylation of unprotected phenols has been developed by direct C−H functionalization catalyzed by PdII. This work features phenol group as a directing group and realizes highly site-selective C−H bond functionalization of phenols to achieve the corresponding products in moderate to excellent yields at 60 °C. The advantages of this reaction include unprecedented C−H functionalization using phenol as a directing group, high regioselectivity, good substrate scope, mild reaction conditions, and high efficiency. To the best of our knowledge, this is the first example of a regioselective C−H alkenylation of unprotected phenols utilizing phenolic hydroxyl group as a directing group. The alkenylation of unprotected tyrosine and intramolecular cyclization are also successfully carried out under this catalytic system in good yields. Furthermore, this novel method enables a late-stage modification of complex phenol-containing bioactive molecules toward a diversity-oriented drug discovery. 相似文献
69.
Chao Dou Xili Jing Shuguang Li Junjun Wu Qingbo Wang 《Optical and Quantum Electronics》2018,50(6):255
The characteristics of a novel dual-core photonic crystal fiber are investigated. In the center of photonic crystal fiber, an energy transmission channel is introduced. The optimized photonic crystal fiber can be used for polarization splitter, which has a short length and low loss. 相似文献
70.
The complexes of Ni (His) 2·H2O, Ni (Gly) 2·2H2O, Pd (His)Cl2·H2O and Pd(Gly) 2·2H2O were synthesized. And the IR, electronic absorption and photoacoustic spectra of these complexes were measured in solid state. The nature of the metal-carboxylate coordinate bond were deduced from the variation in the carboxyl stretching frequencies. And the d-d transition absorptions of these complexes were interpreted quantitatively with the 3d scaling radial theory. Therefore, the structural characterizations were also discussed with their spectral behaviors. 相似文献