• 제목/요약/키워드: McMurry coupling

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Approach to the Total Synthesis of Acanthoside-D

  • Ngoc, Thyen-Truong;Park, Hae-Il
    • 대한약학회:학술대회논문집
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    • 대한약학회 2003년도 Proceedings of the Convention of the Pharmaceutical Society of Korea Vol.2-2
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    • pp.186.4-187
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    • 2003
  • Acanthoside-D, one of major components of Acanthopanacis Cortex, is known as a ginseng-like substance. it has been known to possess diverse biological effects. Acanthoside-D has a furofuran lignan structure and the synthesis of which poses interesting and often unsolved proplems of stereocontrol. Although a few interesting syntheses providing this natural product have been reported, an intermolecular McMurry coupling - intramolecular Mitsunobu cyclization route has not yet been explored. We report here a short and efficient synthetic pathway to the total synthesis of Acanthoside-D from aryl aldehydes and methyl acrylates via Baylis-Hillman reaction, intermolecular McMurry coupling and intramolecular Mitsunobu cyclization as key reaction.

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A First Synthesis and Physical Properties of Asymmetric Anthracenes-Thiophenes Bridged with Ethylene

  • Hwang, Min Ji;Park, Ji Hee;Jeong, Eun Bin;Kang, Il;Lee, Dong Hoon;Park, Chan Eon;Singh, O.M.;Choi, HoJune;Kim, Yoon-Hi;Yoon, Yong Jin;Kwon, Soon-Ki;Lee, Sang-Gyeong
    • Bulletin of the Korean Chemical Society
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    • 제33권11호
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    • pp.3810-3816
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    • 2012
  • Here we report our recent result of a new semiconductor material, which has an asymmetric structure. The synthesized molecules consist of anthracene and thiophene connected by bridged ethylene and substituted with hexyl or dodecyl groups as pendants. The semiconductors were synthesized using a McMurry coupling reaction between anthracene-2-carbaldehyde and corresponding 5-hexyl(or dodecyl)thiophene-2-carbaldehyde. A first investigation of synthesized asymmetry AVHT (9a) and AVDT (9b) for the physical properties showed that they have high oxidation potential and thermal stability. The devices prepared by using AVHT (9a) and AVDT (9b) showed the mobility of $2.6{\times}10^{-2}cm^2/Vs$ and $4.4{\times}10^{-3}cm^2/Vs$, respectively, in solution processed OTFTs.

카바졸을 포함하는 청색 OLED 재료의 합성 (Synthesis and Characterization of Carbazole Derivate for Blue light Emitting Material)

  • 신민기;박현태;장상훈;고혜진;장재완;김윤희;권순기
    • 한국전기전자재료학회:학술대회논문집
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    • 한국전기전자재료학회 2010년도 하계학술대회 논문집
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    • pp.58-58
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    • 2010
  • We designed and synthesized DFPCE blue emitting materials by Mc Murry coupling reaction in order to improve the device efficiency and stability. The structure was confirmed by $^1H$-NMR. The physical properties were characterized by differential scanning calorimetry, thermogravimetric analysis, UV-vis, photoluminescence spectrum and cyclic voltammetry. The decomposition temperature of the material, which correspond to a 5% weight loss upon heating, is $513.58^{\circ}C$. The photoluminescence (PL) spectrum of DFPCE exhibited blue emission at 425 nm in chloroform solution and 462 nm in film.

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Cyclic Host Having Double Bonds as Bridging Units

  • Kyung-Soo Paek;Donald J. Cram
    • Bulletin of the Korean Chemical Society
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    • 제10권6호
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    • pp.568-572
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    • 1989
  • Terphenyl dialdehyde 6 was obtained in 17.4% overall yield through oxidative coupling, methylation, and bisformylation reactions starting from p-cresol, and then coupled intermolecularly using McMurry reaction to give 22-membered macrocylic host 7 in 14.4% yield. In crystal structure host 7 has $C2_v$ symmetry with cis-cis configuration of two double bonds. Four methoxy groups adjacent to double bonds and the other two methoxy groups are directed opposite side, forming a cavity which can nest a guest. The cavity is filled by two inward-turned methyl groups out of four methoxy groups adjacent to double bonds. The kinetically controlled reaction mechanism leading to cis product was proposed. The cation binding properties of 7 were obtained using picrate extraction experiment from $D_2O\; into\; CDCl_3\; at\; 25^{\circ}C$. All the spherical cations (from $Li^+ to NH4^+)$ are complexed with free energies of $7.3{\pm}0.3$ kcal/mol.

Chiral Host. Attempted Synthesis Using McMurry Reaction as a Final Ring Closure Method

  • Kyung-Soo Paek;Donald J. Cram
    • Bulletin of the Korean Chemical Society
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    • 제10권6호
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    • pp.572-577
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    • 1989
  • Using the low valent titanium induced carbonyl-carbonyl coupling reaction, it was attempted to synthesize sterically hindered 17-membered cyclic chiral host 2. The semifinal dialdehyde 12 was obtained through 11 step reactions beginning from p-tert-butylphenol and dibenzofuran. When dialdehyde 12 was treated with $TiCl_3-Zn/Cu,$ only intermolecularly coupled dimer 14 was obtained instead of intramolecularly coupled cyclic alkene 2. The mechanistic consideration leading to 14 was discussed and the cation binding properties of dimer 14 and dicarboxylic intermediate 13 was reported, which implies the significance of the principle of preorganization of host's binding sites prior to complexation.