• Title/Summary/Keyword: ruthenium compounds

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Novel Mononuclear Ruthenium(II) Compounds in Cancer Therapy

  • Anchuri, Shyam Sunder;Thota, Sreekanth;Yerra, Rajeshwar;Devarakonda, Krishna Prasad;Dhulipala, Satyavati
    • Asian Pacific Journal of Cancer Prevention
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    • v.13 no.7
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    • pp.3293-3298
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    • 2012
  • The present study was conducted to evaluate in vivo anticancer activity of two novel mononuclear ruthenium(II) compounds, namely Ru(1,10-phenanthroline)$_2$(2-nitro phenyl thiosemicarbazone)$Cl_2$(Compound $R_1$) and Ru (1,10-phenanthroline)$_2$(2-hydroxy phenyl thiosemicarbazone)$Cl_2$(Compound $R_2$) against Ehrlich ascites carcinoma (EAC) mice and in vitro cytotoxic activity against IEC-6 (small intestine) cell lines and Artemia salina nauplii using MTT [(3-(4,5-dimethylthiazol-2yl)-2,5-diphenyltetrazolium bromide)] and BLT [brine shrimp lethality] assays respectively. The tested ruthenium compounds at the doses 2 and 4 mg/kg body weight showed promising biological activity especially in decreasing the tumor volume, viable ascites cell counts and body weights. These compounds prolonged the life span (% ILS), mean survival time (MST) of mice bearing-EAC tumor. The results for in vitro cytotoxicity against IEC-6 cells showed the ruthenium compound $R_2$ to have significant cytotoxic activity with a $IC_{50}$ value of $20.0{\mu}g/mL$ than $R_1$ ($IC_{50}=78.8{\mu}g/mL$) in the MTT assay and the $LC_{50}$ values of $R_1$ and $R_2$ compounds were found to be 38.3 and $43.8{\mu}g/mL$ respectively in the BLT assay. The biochemical and histopathological results revealed that there was no significant hepatotoxicity and nephrotoxicity associated with the ruthenium administration to mice.

Adsorption of Ruthenium on the alkaline Earth Metal Compounds (알카리토금속 화합물에 의한 루테늄의 흡착)

  • 류경옥;문세기;이근범
    • Journal of the Korean Ceramic Society
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    • v.19 no.2
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    • pp.145-151
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    • 1982
  • Many materials such as silica gel, metallic oxide, activated alumina and alkaline earth metal carbonates were employed as filter media for gaseous oxides of ruthenium volatilized during high level radioactive waste processing. The adsorption efficiency of ruthenium on these materials was evaluated. For the purpose of observing behavior of ruthenium oxides, thermogravimetric analysis of ruthenium oxide in a stream of oxygen was carried out. The rate of volatilization was proportional to the square root of oxygen partial pressure, and increased exponentially with temperature. At $650^{\circ}C$, gaseous ruthenium oxides showed a strongly marked effect of deposition. Of all the materials available, calcium oxide proved to be the best that could be used to adsorb ruthenium.

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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
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    • v.11 no.1
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    • pp.45-49
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    • 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.

Ruthenium Complex-catalyzed Highly Selective Co-oligomerization of Alkenes

  • Ura, Yasuyuki;Tsujita, Hiroshi;Mitsudo, Take-Aki;Kondo, Teruyuki
    • Bulletin of the Korean Chemical Society
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    • v.28 no.12
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    • pp.2139-2152
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    • 2007
  • Ruthenium complex-catalyzed reactions often require highly qualified tuning of reaction conditions with substrates to attain high yield and selectivity of the products. In this review, our strategies for achieving characteristic ruthenium complex-catalyzed co-oligomerization of different alkenes are disclosed: 1) The codimerization of 2-norbornenes with acrylic compounds by new ruthenium catalyst systems of RuCl3(tpy)/Zn [tpy = 2,2':6',2''-terpyridine] or [RuCl2(η6-C6H6)]2/Zn in alcohols, 2) A novel synthesis of 2-alkylidenetetrahydrofurans from dihydrofurans and acrylates by zerovalent ruthenium catalysts, such as Ru(η4-cod)(η6-cot) [cod = 1,5-cyclooctadiene, cot = 1,3,5-cyclooctatriene] and Ru(η6-cot)(η2-dmfm)2 [dmfm = dimethyl fumarate], 3) Regio- and stereoselective synthesis of enamides by Ru(η6-cot)(η2-dmfm)2-catalyzed codimerization of N-vinylamides with alkenes, and 4) Unusual head-to-head dimerization of styrenes and linear codimerization of styrenes with ethylene by Ru(η6-cot)(η2-dmfm)2 catalyst in the presence of primary alcohols.

Study on Electrochemical Characteristics and Fabrication of Catalytic Electrode (복합 촉매 전극의 제조 및 전기화학적 특성에 관한 연구)

  • 민병승;정원섭;김광호;민병철;이미혜
    • Journal of the Korean institute of surface engineering
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    • v.35 no.6
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    • pp.401-407
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    • 2002
  • Most of organic compounds discharged from industrial wastewater are treated by chemical oxidation, adsorption and biodegradable process. This process has been demanded a new advanced environmental wastewater treatment process. From this point of view, an electrochemical oxidation process using electrocatalysts has been developed for the destruction of organic compounds. Through this study, a ruthenium oxide/iridium oxide supported on titanium expanded metal was fabricated by thermal decomposition method and its performance was excellent during this experiment.

New Ruthenium Complexes for Semiconductor Device Using Atomic Layer Deposition

  • Jung, Eun Ae;Han, Jeong Hwan;Park, Bo Keun;Jeon, Dong Ju;Kim, Chang Gyoun;Chung, Taek-Mo
    • Proceedings of the Korean Vacuum Society Conference
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    • 2014.02a
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    • pp.363-363
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    • 2014
  • Ruthenium (Ru) has attractive material properties due to its promising characteristics such as a low resistivity ($7.1{\mu}{\Omega}{\cdot}cm$ in the bulk), a high work function of 4.7 eV, and feasibility for the dry etch process. These properties make Ru films appropriate for various applications in the state-of-art semiconductor device technologies. Thus, it has been widely investigated as an electrode for capacitor in the dynamic random access memory (DRAM), a metal gate for metal-oxide semiconductor field effect transistor (MOSFET), and a seed layer for Cu metallization. Due to the continuous shrinkage of microelectronic devices, better deposition processes for Ru thin films are critically required with excellent step coverages in high aspect ratio (AR) structures. In these respects, atomic layer deposition (ALD) is a viable solution for preparing Ru thin films because it enables atomic-scale control of the film thickness with excellent conformality. A recent investigation reported that the nucleation of ALD-Ru film was enhanced considerably by using a zero-valent metallorganic precursor, compared to the utilization of precursors with higher metal valences. In this study, we will present our research results on the synthesis and characterization of novel ruthenium complexes. The ruthenium compounds were easy synthesized by the reaction of ruthenium halide with appropriate organic ligands in protic solvent, and characterized by NMR, elemental analysis and thermogravimetric analysis. The molecular structures of the complexes were studied by single crystal diffraction. ALD of Ru film was demonstrated using the new Ru metallorganic precursor and O2 as the Ru source and reactant, respectively, at the deposition temperatures of $300-350^{\circ}C$. Self-limited reaction behavior was observed as increasing Ru precursor and O2 pulse time, suggesting that newly developed Ru precursor is applicable for ALD process. Detailed discussions on the chemical and structural properties of Ru thin films as well as its growth behavior using new Ru precursor will be also presented.

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Development of Ruthenium/TEMPO/Nitrate Catalyst System for Efficient Oxidation of Isosorbide (아이소소바이드의 효과적 산화반응을 위한 루테늄/템포/나이트레이트 촉매 시스템 개발)

  • Irshad, Mobina;Yu, Jung-Ah;Oh, Youngtak;Kim, Jung Won
    • Applied Chemistry for Engineering
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    • v.33 no.1
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    • pp.103-108
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    • 2022
  • This research work reports the development of a Ruthenium/2,2,6,6-tetramethylpiperidine-N-oxyl (TEMPO)/nitrate catalyst system for the highly selective transformation of isosorbide (1,4:3,6-dianhydro-D-glucitol) to isosorbide-diketone (2,6-dioxabicyclo (3,3,0)octan-4,8-one). Isosorbide is a critical platform molecule for future manufacturing processes. TEMPO has been utilized to convert alcohols to carbonyl compounds for a long time. The optimal chemical reaction condition was found to be when using isosorbide (0.5 mmol) with supported Ru (10 mol%), TEMPO (5 mol%), and sodium nitrate (0.03 mmol) in the presence of acetic acid (3 ml) as a solvent at 50 ℃ and 1 atm oxygen pressure. This catalyst system demonstrated good selectivity (> 97%) and yield (87%) with respect to the desired product, in addition to a putative catalytic double oxidation mechanism.

Synthesis and Photovoltaic Performance of Long Wavelength Absorption Dyes for the Dye Sensitized Solar Cell (장 파장 대 태양광을 흡수하는 염료감응형태양전지에 대한 염료와 합성)

  • Kim, Sangah;Yoon, Jooyoung;Kim, Jaehong
    • 한국신재생에너지학회:학술대회논문집
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    • 2010.06a
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    • pp.89.2-89.2
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    • 2010
  • The dye-sensitized solar cell (DSSC) is a device for the conversion of visible light into electricity, based on the sensitization of wide bandgap semiconductors. The performance of the cell mainly depends on a dye used as sensitizer. The absorption spectrum of the dye and the anchorage of the dye to the surface of $TiO_2$ are important parameters determining the efficiency of the cell. Generally, transition metal coordination compounds(ruthenium polypyridyl complexes) are used as the effective sensitizers, due to their intense charge-transfer absorption in the whole visible range and highly efficient metal-to ligand charge transfer. However, ruthenium polypyridyl complexes contain a heavy metal, which is undesirable from point of view of the environmental aspects. Moreover, the process to synthesize the complexes is complicated and costly. Alternatively, organic dyes can be used for the same purpose with an acceptable efficiency. The advantages of organic dyes include their availability and low cost. We designed and synthesized a series of organic sensitizers containing long wavelength absorption-chromophores for the dye sensitized solar cell. The DSSC composed of Blue-chromophores for the sensitization absorbed long wavelength region which is different also applied into the dye-cocktail (mixing) system. The photovoltaic property of DSSCs organic long wavelength absorption-chromophores were measured and evaluated by comparison with that of individual chromophores.

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Synthesis and Photovoltaic Performance of NIR Absorption Dyes for the Dye Sensitized Solar Cell (NIR 흡수 염료를 이용한 염료감응형 태양전지)

  • Kim, Sangah;Jung, Miran;Lee, Minkyung;Kim, Jaehong
    • 한국신재생에너지학회:학술대회논문집
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    • 2011.05a
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    • pp.118.1-118.1
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    • 2011
  • The dye-sensitized solar cell (DSSC) is a device for the conversion of visible light into electricity, based on the sensitization of wide bandgap semiconductors. The performance of the cell mainly depends on a dye used as sensitizer. The absorption spectrum of the dye and the anchorage of the dye to the surface of TiO2 are important parameters determining the efficiency of the cell. Generally, transition metal coordination compounds(ruthenium polypyridyl complexes) are used as the effective sensitizers, due to their intense charge-transfer absorption in the whole visible range and highly efficient metal-to ligand charge transfer. However, ruthenium polypyridyl complexes contain a heavy metal, which is undesirable from point of view of the environmental aspects. Moreover, the process to synthesize the complexes is complicated and costly. Alternatively, organic dyes can be used for the same purpose with an acceptable efficiency. The advantages of organic dyes include their availability and low cost. We designed and synthesized a series of organic sensitizers containing long wavelength absorption-chromophores for the dye sensitized solar cell. The DSSC composed of Blue-chromophores for the sensitization absorbed long wavelength region which is different also applied into the dye-cocktail (mixing) system. The photovoltaic property of DSSCs organic long wavelength absorption-chromophores were measured and evaluated by comparison with that of individual chromophores.

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Dynamic Kinetic Resolutions and Asymmetric Transformations by Enzyme-Metal Combo Catalysis

  • Kim, Mahn-Joo;Ahn, Yang-Soo;Park, Jai-Wook
    • Bulletin of the Korean Chemical Society
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    • v.26 no.4
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    • pp.515-522
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    • 2005
  • Enzyme-metal combo catalysis is described as a useful methodology for the synthesis of optically active compounds. The key point of the method is the use of enzyme and metal in combination as the catalysts for the complete transformation of racemic substrates to single enantiomeric products through dynamic kinetic resolution (DKR). In this approach, enzyme acts as an enantioselective resolving catalyst and metal does as a racemizing catalyst for the efficient DKR. Three kinds of enzyme-metal combinations - lipase-ruthenium, subtilisin-ruthenium, and lipase-palladium –have been developed as the catalysts for the DKRs of racemic alcohols, esters, and amines. The scope of the combination catalysts can be extended to the asymmetric transformations of ketones, enol acetates, and ketoximes via the DKRs. In most cases studied, enzyme-metal combo catalysis provided enantiomerically-enriched products in high yields.