• Title/Summary/Keyword: Ruthenium catalyst

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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.

Efficient Oxidative Scission of Alkenes or Alkynes with Heterogeneous Ruthenium Zirconia Catalyst (루테늄 지르코니아 불균일 촉매를 이용한 알켄 또는 알킨의 효과적인 산화절단반응)

  • Irshad, Mobina;Choi, Bong Gill;Kang, Onyu;Hong, Seok Bok;Hwang, Sung Yeon;Heo, Young Min;Kim, Jung Won
    • Applied Chemistry for Engineering
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    • v.27 no.6
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    • pp.659-663
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    • 2016
  • The efficiency of a heterogeneous ruthenium zirconia catalyst ($Ru(OH)_x/ZrO_2$) was demonstrated to the selective oxidative transformation of alkenes or alkynes. The scissions of C-C double bonds to aldehydes and triple bonds to diketones or carboxylic acids were carried out with (diacetoxyiodo)benzene as an oxidant under dichloromethane (5 mL)/water (0.5 mL) solvent system at $30^{\circ}C$ for wide range of substrates. The $Ru(OH)_x/ZrO_2$composite showed higher catalytic activity and selectivity than other ruthenium-based homogeneous or heterogeneous catalysts for the scission reaction. The catalyst exhibited a high mechanical stability, and no leaching of the metal was observed during the reaction. These features ensured the reusability of the catalyst for several times for the oxidative cleavage of unsaturated hydrocarbons.

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.