• Title/Summary/Keyword: Ruthenium complex

Search Result 58, Processing Time 0.021 seconds

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
    • /
    • v.28 no.6
    • /
    • pp.921-928
    • /
    • 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.

Transient Absorption Spectra of Phenothiazine Derivative in the Vesicle System Containing Ru$^{2+}$ Complex as a Sensitizer

  • Park, Yong-Tae;Kim, Young-Doo;Burkhart, Richard D.;Caldwell, Norris J.
    • Bulletin of the Korean Chemical Society
    • /
    • v.9 no.2
    • /
    • pp.84-87
    • /
    • 1988
  • The Photophysical and photochemical properties of Ruthenium bipyridine with two long hydrocarbon chains, $[Ru(bipy)_2(dhbipy)]^{2+}$ and transient phenothiazine derivative cation radical $(PTD^+)$ in the cationic vesicle were studied. Transient absorption spectra of cation radical of phenothiazine derivative in the vesicle system containing the $Ru^{2+}$ complex, $[Ru(bipy)_2(dhbipy)]^{2+}$, (1) as sensitizer and phenothiazine derivative as electron donor was observed by XeCl excimer laser photolysis system. Thus the excited ruthenium complex would be quenched by phenothiazine derivative(PTD) reductively in the vesicle system. The quenching rate constant($K_Q$) of $Ru^{2+}$ with two long hydrocarbon chains in the vesicle by PTD was $9.6{\times}10^8M^{-1}S^{-1}$. The absorption decay kinetics showed that lifetime of phenothiazine derivative cation radical is a value in the 4-8m sec range.

Synthesis, Characterizations, and Intramolecular Quenching Behavior of an Axially-Linked Trinuclear Molecular Wire Containing Ruthenium(II) Porphycenes

  • Abe, Masaaki;Ashigara, Shiho;Okawara, Toru;Hisaeda, Yoshio
    • Rapid Communication in Photoscience
    • /
    • v.4 no.1
    • /
    • pp.22-24
    • /
    • 2015
  • A new trinuclear complex $[Ru(TPrPc)(CO)]_2[Ru(pytpy)_2](PF_6)_2$ (TPrPc = 2,7,12,17-tetra-n-propylporphycenato dianion and pytpy = 4'-(4-pyridyl)-2,2':6',2"-terpyridine) has been synthesized and characterized as the first example of a discrete molecular wire containing metalloporohycenes as a building block. The trinuclear complex shows multiple-step redox behavior in 0.1 M n-$Bu_4NPF_6$-dichloromethane. The mononuclear $[Ru(pytpy)_2]^{2+}$ precursor shows emission at 640 nm (deaerated acetone, 298 K) upon illumination at the metal-to-ligand charge transfer (MLCT) band at 495 nm, but the trinuclear molecular wire is found to be non-emissive upon photoexcitation at the central $[Ru(pytpy)_2]^{2+}$ entity, indicating an efficient quenching ability of the axially-linked, ruthenium(II)-porphycene chromophores in an intramolecular fashion.

Ruthenium Complex Catalyzed Synthesis of 2-Substituted Benzoxazoles from o-Aminophenol and Alcohol with Spontaneous Hydrogen Evolution

  • Keun-Tae Huh;Sang Chul Shim
    • Bulletin of the Korean Chemical Society
    • /
    • v.14 no.4
    • /
    • pp.449-452
    • /
    • 1993
  • o-Aminophenols react with alcohols in the presense of a catalytic amount of ruthenium catalyst at 180$^{\circ}C$ to give 2-substituted benzoxazole in good yield. The yields of 2-substituted benzoxazoles were affected by the yield of N-alkylation compound from o-aminophenol and alcohol as starting materials. During the reaction, a stoichiometric amount of hydrogen was spontaneously evolved into the gas phase.

Ruthenium Complex-Catalyzed Synthesis of Indoles from N-Substituted Anilines and Alkanolamines

  • 이동엽;조찬식;김주의;윤영주;심상철;송한철
    • Bulletin of the Korean Chemical Society
    • /
    • v.17 no.12
    • /
    • pp.1132-1135
    • /
    • 1996
  • N-Substituted anilines react with triethanolamine at 180℃ in the presence of a catalytic amount of tris(triphenylphosphine)ruthenium(Ⅱ) chloride to give the corresponding 1-substituted indoles in good to high yields. Similar treatment of the anilines with N-benzyldiethanolamine or triisopropanolamine in place of triethanolamine also affords the indoles in good yields. An intermolecular alkyl group transfer between anilines and alkanolamines is assumed to be the key step of these reactions.

Ruthenium Catalyzed Synthesis of 1-Substituted Perhydroazocines from Primary Amines and 1,7-Heptanediol

  • Shim, Sang-Chul;Doh, Chil-Hoon;Yoon, Jeum-Ho;Lee, Dong-Yub;Youn, Young-Zoo
    • Bulletin of the Korean Chemical Society
    • /
    • v.12 no.6
    • /
    • pp.649-652
    • /
    • 1991
  • The reaction of primary aromatic amines with 1,7-heptanediol in the presence of a catalytic amount of ruthenium complex in dioxane at $180^{\circ}C$ for 24 hours gave the corresponding 1-substituted perhydroazocines in moderate yield.

Enhanced Electrical Properties of Light-emitting Electrochemical Cells Based on PEDOT:PSS incorporated Ruthenium(II) Complex as a Light-emitting layer

  • Gang, Yong-Su;Park, Seong-Hui;Lee, Hye-Hyeon;Jo, Yeong-Ran;Hwang, Jong-Won;Choe, Yeong-Seon
    • Proceedings of the Korean Vacuum Society Conference
    • /
    • 2010.08a
    • /
    • pp.139-139
    • /
    • 2010
  • Ionic Transition Metal Complex based (iTMC) Light-emitting electrochemical cells (LEECs) have been drawn attention for cheap and easy-to-fabricate light-emitting device. LEEC is one of the promising candidate for next generation display and solid-state lighting applications which can cover the defects of current commercial OLEDs like complicated fabrication process and strong work-function dependent sturucture. We have investigated the performance characteristics of LEECs based on poly (3, 4-ethylenedioxythiophene):poly (styrene sulfonate) (PEDOT:PSS)-incorporated transition metal complex, which is tris(2, 2'-bipyridyl)ruthenium(II) hexafluorophosphate in this study. There are advantages using conductive polymer-incorporated luminous layer to prevent light disturbance and absorbance while light-emitting process between light-emitting layer and transparent electrode like ITO. The devices were fabricated as sandwiched structure and light-emitting layer was deposited approximately 40nm thickness by spin coating and aluminum electrode was deposited using thermal evaporation process under the vacuum condition (10-3Pa). Current density and light intensity were measured using optical spectrometer, and surface morphology changes of the luminous layer were observed using XRD and AFM varying contents of PEDOT:PSS in the Ruthenium(II) complex solution. To observe enhanced ionic conductivity of PEDOT:PSS and luminous layer, space-charge-limited-currents model was introduced and it showed that the performances and stability of LEECs were improved. Main discussions are the followings. First, relationship between film thickness and performance characteristics of device was considered. Secondly, light-emitting behavior when PEDOT:PSS layer on the ITO, as a buffer, was introduced to iTMC LEECs. Finally, electrical properties including carrier mobility, current density-voltage, light intensity-voltage, response time and turn-on voltages were investigated.

  • PDF

Noncovalently Linked Zinc Porphyrin-Ru(bpy)3 Dyad Assembled via Axial Coordination

  • Kim, Dol;Shin, Eun-Ju
    • Bulletin of the Korean Chemical Society
    • /
    • v.24 no.10
    • /
    • pp.1490-1494
    • /
    • 2003
  • Noncovalently linked electron donor-acceptor dyad consisting of zinc tetratolylporphyrin and pyridine appended ruthenium trisbipyridine comlex was prepared, via axial coordination of pyridine moiety in ruthenium trisbipyridine complex on zinc tetratolylporphyrin. For the purpose of comparison, axial coordination of pyridine-appended 2,2'-bipyridine on zinc tetratolylporphyrin was also investigated. The Kvalues were detemined based on absorption of fluorescence studies. The fluorescence of zinc teratolylporphrin was efficiently quenched upon axial coordination of pyridine moiety, prbably due to the photoinduced electron transfer from zinc tetrtolylporphyrin to ruthenium trisbipyridine, supported by free enegy estimation.

Ruthenium Complex Catalyzed Syntehesis of Diamino Compounds from ${\alpha},{\omega}$-Diols and Secondary Amines

  • Keun-Tae Huh;Sang Chul Shim;Chll Hoon Doh
    • Bulletin of the Korean Chemical Society
    • /
    • v.11 no.1
    • /
    • pp.45-49
    • /
    • 1990
  • ${\alpha},{\omega}$-Diols react with secondary amines in the presence of a catalytic amount of ruthenium catalyst at $180^{\circ}C$ to give diamino compounds in good to excellent yields. The yield of diamino compound was affected by the molar ratio of ${\alpha},{\omega}$-diol to secondary amine. The reaction is affected by the nature of the phosphorus ligands employed and the effectiveness of the added ligand is completely different depending on the chain length of the ${\alpha},{\omega}$-diol. The reaction between ethylene glycol and primary amine in the presence of a catalytic amount of ruthenium catalyst gave 1,4-disubstituted piperazine.