• Title/Summary/Keyword: 4,4'-Bipyridine

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A Synthesis and Characterization of Pt(II) Complexes with Bipyrimidin-based Back-bone System (비피리미딘계 배위자를 골격으로 하는 Pt(II)착체의 합성 및 특성)

  • Son, Seokhwan;Ahn, Hogeun;Chung, Minchul
    • Korean Chemical Engineering Research
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    • v.54 no.4
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    • pp.555-559
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    • 2016
  • In this study, new platinum complexes were synthesized utilizing the ligand of a 2,2'-bispyrimidine (bpim), 2,2'-bipyridine (bpy), 5,5'-dimethyl-2,2'-bipyridine (5,5-mebpy), 5'-bromo-2,2'-bipyridine (5-brbpy), 5,5'-dibromo-2,2'-bipyridine (5,5-brbpy), 4,4'-dimethyl-2,2'-bipyridine (4,4-mebpy), 4,4'-dihexyl-2,2'-Bipyridine (4,4-hebpy), 1,10'-Phenanthroline (phen), 3,4,7,8'-tetramethyl-1,10'-Phenanthroline (3,4,7,8-phen). In order to determine chemical structure of Synthesized platinum complexes, $^1H(^{13}C)$-NMR, UV-vis and FT-IR were used and optical physics and chemical properties were measured PL. In the case of platinum complexes, wavelength has been identified 356~421 nm. Quantum efficiency in DMSO solution was appeared 0.05~0.46.

Kinetics and Mechanism of the Oxidation of Substituted Benzyl Alcohols by Cr(VI)-4,4'-Bipyridine Complex (크롬(VI)-4,4'-Bipyridine 착물에 의한 치환 벤질 알코올류의 산화반응 속도론과 메카니즘)

  • Kim, Young-Sik;Park, Young-Cho
    • Journal of the Korea Academia-Industrial cooperation Society
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    • v.13 no.1
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    • pp.462-469
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    • 2012
  • Cr(VI)-4,4'-bipyridine complex(4,4'-bipyridinium dichromate) was synthesized by the reaction of 4,4'-bipyridine with chromium trioxide in H2O, and characterized by IR, ICP. The oxidation of benzyl alcohol using 4,4'-bipyridinium dichromate in various solvents showed that the reactivity increased with the increase of the dielectric constant(${\varepsilon}$), in the order: cyclohexene$CH_3$, H, m-Br, m-$NO_2$) smoothly in N,N'-dimethylformamide. Electron-donating substituents accelerated the reaction, whereas electron acceptor groups retarded the reaction. The Hammett reaction constant(${\rho}$) was -0.63(303K). The observed experimental data have been rationalized as follows; the proton transfer occurs after the prior formation of a chromate ester in the rate determining step.

Photochemical Hydrogen Evolution in K4Nb6O17 Semiconductor Particles Sensitized by Phosphonated Trisbipyridine Ruthenium Complexes

  • Jung, Young-Hee;Shim, Hyun-Kwan;Kim, Hyun-Woo;Kim, Yeong-Il
    • Bulletin of the Korean Chemical Society
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    • v.28 no.6
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    • pp.921-928
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    • 2007
  • Three different phosphonated trisbipyridine ruthenium complexes, [(4-CH3-4'-CH2PO(OH)2-2,2'-bipyridine)- (bpy)2Ru]·(PF6)2 (Ru-P1), [(4-CH3-4'-CH2PO(OH)2-2,2'-bipyridine)3Ru]·(PF6)2 (Ru-P2), and [(4,4'-CH2PO- (OH)2-2,2'-bipyridine)3Ru]·(PF6)2 (Ru-P3) were synthesized and their photochemical and electrochemical properties were studied. These ruthenium complexes were strongly adsorbed on the surface of the layered metal oxide semiconductor K4Nb6O17 that was partially acid-exchanged and sensitized up to pH 10, while the carboxylated ruthenium complex, (4,4'-COOH-2,2'-bipyridine)3Ru·Cl2 (Ru-C) that was previously studied was sensitized only below pH 4. The visible light water reduction at K4Nb6O17 that was internally platinized and sensitized by these phosphonated Ru-complexes was comparatively studied using a reversible electron donor iodide.

Electrochemical Properties and Synthesis of Poly(ether)tailed Cobalt(II)bipyridine Complex (폴리(에테르)사슬이 결합된 Cobalt(II)bipyridine 착물의 합성과 전기화학적 성질)

  • Kim, II Kwang;Jun, II Chul;Murray, Royce W.
    • Analytical Science and Technology
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    • v.9 no.3
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    • pp.292-301
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    • 1996
  • The synthesis of poly(ether)tailed bipyridine complex as redox reaction probes has advanced attempts to interpret very slow diffusion and heterogeneous electron transfer. Diffusion coefficients as low as $1.5{\times}10^{-15}cm^2/s$ have been observed for the oxidation of neat $Co(bpy(ppgm)_2)_{3^-}(ClO_4)_2$ with $LiClO_4$ electrolyte. Heterogeneous electron transfer rate constants of materials were found to vary with diffusion coefficient. The decrease in k as the diffusion coefficient decreases was actually caused by the decreasing D. Diffusion coefficient for compound of strong ion pairing anion($ClO{_4}^-$) was much smaller than the diffusion coefficient for compound of weak ion pairing anion($CF_3COO^-$).

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