• 제목/요약/키워드: Coupling reactions

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팔라듐 촉매를 이용한 퀴놀론핵과 Heteroaryl Stannes의 결합 - C-7 heteroaryl 쿼놀론 유도체의 합성 - (Palladium-Catalyzed Coupling between Quinolone Moieties and Heteroaryl Stannes - Synthesis of C-7 heteroaryl Quinolone Derivatives -)

  • 남상훈;함원훈;김기수;임태균;양재권
    • 약학회지
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    • 제37권6호
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    • pp.615-620
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    • 1993
  • The cross-coupling reaction of organo tin reagents with a variety of organic halides, catalyzed by palladium, provides a novel method for generating a carbon-carbon bond. We used this method for the antibacterial agents, and synthesis of new quinolone derivatives which have carbon-carbon bond at C-7 position of general quinolone moieties. Aryl tin, quinolone moieties, and palladium catalyst were refluxed in DMF to afford new quinolone derivatives. This palladium catalyzed coupling reactions have capacity for further synthetic elaboration.

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Synthesis of Neopentyl Biphenylsulfonates Using the Suzuki-Miyaura Reaction

  • Cho, Chul-Hee;Kim, Chul-Bae;Sun, Myung-Chul;Park, Kwang-Yong
    • Bulletin of the Korean Chemical Society
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    • 제24권11호
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    • pp.1632-1636
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    • 2003
  • Palladium-catalyzed cross-coupling reactions of neopentyloxysulfonylphenyl bromides with arylboronic acids provided a variety of neopentyl biphenylsulfonates in good yields. 2-Bromo- and 4-bromobenzenesulfonates underwent the coupling reaction more rapidly than 3-bromobenzenesulfonate, while chlorobenzenesulfonate did not produce the coupling product under the standard reaction conditions.

Preparation of Graphene Based PdOx and CuOx/MnOx Nanocomposites and Their Catalytic Applications in C-C Coupling and CH3SH Decomposition Reactions

  • 이경훈;박준범
    • 한국진공학회:학술대회논문집
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    • 한국진공학회 2014년도 제46회 동계 정기학술대회 초록집
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    • pp.175.2-175.2
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    • 2014
  • Graphene (G) has been modified with palladium, copper, and manganese oxide nanoparticles (NPs), and their catalytic applications have been studied in C-C coupling reactions and methylmercaptan (CH3SH) decomposition reactions. In this research, graphite oxide (GO) sheets were exfoliated and oxidized from graphite powder and impregnated with metal precursors including Pd2+, Cu2+, and Mn2+. The thermal treatments of the metal impregnated GO in preferred gas environments produced Pd NPs on graphene (Pd/G), PdO NPs on GO (PdO/GO), and CuOx and MnOx NPs on graphene (CuOx/MnOx/G). In case of Pd/G and PdO/GO, the TEM images show that, although the mean size of the Pd NPs changed significantly before and after the C-C coupling reaction, that of the PdO NPs didn't, implying that the PdO/GO was superior to Pd/G in terms of the recyclability. Also, we demonstrate that the CuOx/MnOx/G exerts the excellent catalytic efficiency in CH3SH decomposition reaction comparing with conventional catalysts. The chemical and electronic structural changes were investigated using XRD and XPS.

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Polymer-supported Zinc Tetrahalide Catalysts for the Coupling Reactions of CO2 and Epoxides

  • Lee, Bo-Ra;Ko, Nan-Hee;Ahn, Byoung-Sung;Cheong, Min-Serk;Kim, Hoon-Sik;Lee, Je-Seung
    • Bulletin of the Korean Chemical Society
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    • 제28권11호
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    • pp.2025-2028
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    • 2007
  • Homogeneous zinc tetrahalide complexes, highly active catalysts for the coupling reactions of alkylene oxide and CO2 produce alkylene carbonates, were heterogenized due to their tendency to decompose produced alkylene carbonates during the distillation process. Heterogenization of homogeneous zinc tetrahalide complexes was achieved by polymerizing 1-alkyl-3-vinylimidazolium zinc tetrahalides. These polymerized zinc tetrahalide catalysts displayed similar activities to their corresponding monomeric analogues for the coupling reactions of carbon dioxide with ethylene oxide (EO) or propylene oxide (PO) to produce ethylene carbonate (EC) or propylene carbonate (PC). TGA studies showed that the polymer-supported zinc tetrahalide catalysts are thermally stable up to 320 oC. The catalyst recycle test showed that the supported catalysts could be reused over six times. After removal of the polymer-supported catalyst through a simple filtration, EC was able to be isolated without decomposition.

Evolution of reaction zones in reactive barriers consisting of calcite and glass beads

  • Jeong Gon, Kim;Gwang Man, Lee;Ik Hwan, Go
    • 한국지하수토양환경학회:학술대회논문집
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    • 한국지하수토양환경학회 2004년도 총회 및 춘계학술발표회
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    • pp.19-22
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    • 2004
  • Two-dimensional modeling studies using TOUGHREACT were conducted to investigate the coupling between flow and transport developed as a consequence of differences in density, dissolution/ precipitation, and medium heterogeneity. The model includes equilibrium reactions for aqueous species, kinetic reactions between tile solid phases and aqueous constituents, and full coupling of porosity and permeability changes resulting from precipitation and dissolution reactions in porous media. Generally, the evolutions in the concentrations of the aqueous phase are intimately related to the reaction-front dynamics. Plugging of the medium contributed to significant transients in patterns of flow and mass transport.

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