• Title/Summary/Keyword: Olefin

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Asymmetric Synthesis of (+)-trans-Aerangis Lactone

  • Kim, Aejin;Sharma, Satyasheel;Kwak, Jong Hwan;Kim, In Su
    • Bulletin of the Korean Chemical Society
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    • v.34 no.1
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    • pp.75-78
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    • 2013
  • Asymmetric synthesis of (+)-trans-aerangis lactone was achieved from commercially available 1-hexanol or 1-hexanal in four steps via iridium-catalyzed diastereoselective and enantioselective carbonyl crotylation from the alcohol or aldehyde oxidation level, and ruthenium-catalyzed olefin metathesis.

Vinylation of $\beta$-Acetoxyvinyl Mercurials with Olefins by Palladium (Ⅱ) Salt

  • Kim, Jin-Il;Lee, Jong-Tae
    • Bulletin of the Korean Chemical Society
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    • v.7 no.2
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    • pp.142-145
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    • 1986
  • Vinylation of highly hindered ${\beta}$-acetoxyvinyl mercurials with olefins in acetonitrile at room temperature in the presence of cupric chloride, as a reoxidant for the palladium, and a catalytic amount of $LiPdCl_3$ gave the corresponding conjugated dienes in moderate to good yields. The (E) or (Z) geometry in vinyl mercurials was retained in the vinylated products. The reaction was tolerant of a wide variety of functional groups ($CO_2$R, CN, OR, OAc) on either the vinyl mercurial or olefin compounds.

Reactions of Metal Catalysts with Polar Vinyl Monomers

  • Jordan Richard F.
    • Proceedings of the Polymer Society of Korea Conference
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    • 2006.10a
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    • pp.153-154
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    • 2006
  • The development of metal catalysts that can polymerize or copolymerize "polar" $Ch_2=CHX$ monomers by insertion mechanisms would significantly expand the scope of metal-catalyzed polymerization and enable the synthesis of new materials with enhanced properties. We have studied the reactions of single-site olefin polymerization catalysts with vinyl chloride, acrylonitrile, and vinyl ethers, in order to probe monomer coordination trends, insertion rates and regioselectivity, and the structures and reactivity of metal alkyls that contain functional groups on the alpha and beta positions of the alkyl chain. These studies provide insights to the key issues that underlie the "polar monomer" problem. Copolymerization of olefins and selected vinyl ethers has been achieved.

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The Effect of Lubricity Improvement by Biodiesel Components (바이오디젤 구성성분에 따른 윤활성향상 효과)

  • Lim, Young-Kwan;Park, So-Ra;Kim, Jong-Ryeol;Yim, Eui-Soon;Jung, Choong-Sub
    • Applied Chemistry for Engineering
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    • v.21 no.6
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    • pp.684-688
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    • 2010
  • Biodiesel produced from the reaction of methanol and triglyceride which is the main component of animal fats and vegetable oils is known for remarkable lubricity. In this study, the lubricity of 3 kinds of biodiesel came from vegetable oils such as soybean oil, palm oil, and perilla oil and 2 kind of biodiesel which were produced from beef tallow and pork lard were analyzed using HFRR (High frequency reciprocating rig). In HFRR test result, the lubricity of perilla and soybean's biodiesel was higher than other biodiesels. After analysis of biodiesel components by GC-MS and determination of the lubricity of pure biodiesel components using HFRR, it was found that a higher olefin content and long alkyl chaining biodiesel had an excellent lubricity property.

Bayberry Tannin as Stabilizer for the Synthesis of Highly Active and Reusable Heterogeneous Pd Catalysts and Their Application in the Catalytic Hydrogenation of Olefins

  • Chen, Chen;Lv, Guang;Huang, Xin;Liao, Xue Pin;Zhang, Wen Hua;Shi, Bi
    • Bulletin of the Korean Chemical Society
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    • v.33 no.2
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    • pp.403-408
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    • 2012
  • In this study, the homogenous Pd nanoparticles (Pd NPs) were first prepared with bayberry tannin (BT) as the stabilizers. Subsequently, the obtained bayberry tannin-stabilized Pd nanoparticles (BT-Pd) were immobilized onto ${\gamma}-Al_2O_3$ to prepare heterogeneous ${\gamma}-Al_2O_3$-BT-Pd catalysts. Fourier Transformation Infrared Spectrum (FTIR) and X-ray Photoelectron Spectroscopy (XPS) analyses confirmed that the Pd NPs were well stabilized by the phenolic hydroxyl groups of BT. Transmission Electron Microscopy (TEM) observation indicated that the diameter of the Pd NPs can be effectively controlled in the range of 4.2-16.0 nm by varying the amount of BT. It is found that the ${\gamma}-Al_2O_3$-BT-Pd catalysts exhibit highly activity for various olefin hydrogenations. For example, the initial TOF (turnover frequency) of the ${\gamma}-Al_2O_3$-BT-Pd in the allyl alcohol hydrogenation is as high as $12804 mol{\cdot}mol^{-1}{\cdot}h^{-1}$. Furthermore, the ${\gamma}-Al_2O_3$-BT-Pd can be reused 5 times without significant loss of activity, exhibiting a superior reusability as compared with conventionally prepared ${\gamma}-Al_2O_3$-Pd catalysts.