• Title/Summary/Keyword: heck coupling

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Synthesis of Dimeric Oligodeoxyribonucleotide (이합체성 올리고디옥시리보핵산의 합성)

  • Song, Jeong-Sup
    • Journal of the Korea Academia-Industrial cooperation Society
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    • v.8 no.6
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    • pp.1566-1571
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    • 2007
  • Oligodeoxyribonucleotide bearing the di-acetylenic linkage has been prepared. Staring from 5-Iodo-2'-deoxyuridine(1), a four-step sequence, consisting of the Pd(0)-catalyzed Heck-type C-C coupling with acetylenic group, protection of 5'-hydroxy group, generation of acetylenic hydrogen, and Glaser oxidative coupling reaction leads to the dimeric oligodeoxyribonucleotide(5).

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Synthesis of Palladium Nanocubes/Nanorods and Their Catalytic Activity for Heck Reaction of Iodobenzene

  • Ding, Hao;Dong, Jiling
    • Applied Microscopy
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    • v.46 no.2
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    • pp.105-109
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    • 2016
  • Palladium has been used as a catalyst not only in Suzuki and Heck cross coupling reaction in organic chemistry, but also in automobile industry for the reduction of vehicle exhausts. The catalytic activity of Pd nanoparticles depends strongly on their size and exposed crystalline facets. In this study, the single crystalline palladium nanocubes/nanorods were prepared in the presence of polyvinyl pyrrolidone (PVP) and potassium bromide (KBr) using the polyol method. Selected area diffraction pattern and high-resolution transmission electron microscopy (TEM) were performed by TEM. The result shows that the ratio of KBr/PVP is the key factor to determine whether the product is cubes or rods. The as-prepared Pd nanocubes were highly uniform in both size and shape. The ordered packing structures including monolayer and multilayer can be fabricated via the rate-controlled evaporation of solution solvent. The catalytic activity of these Pd nanocubes towards heck reaction of iodobenzene with acrylate or acrylic acid was found to be higher than that of Pd nanorods. We suspect it is caused by the difference of energy state while Pd nanocubes is {100} plane and nanorods is {111} plane.

Synthesis and Light-Emitting Properties of Cyanofluorenylvinylene and Cyanophenylenevinylene-Based Alternating Copolymers by Heck Reaction

  • Jin, Sung-Ho;Kim, Mi-Yeon;Kang, Seung-Yun;Gal, Yeong-Soon
    • 한국정보디스플레이학회:학술대회논문집
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    • 2003.07a
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    • pp.974-977
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    • 2003
  • A new series of statistical alternating EL copolymer, poly[bis{2-(4-phenylenevinylene)-2-cyanoethenyl}- 9,9-dihexyl-9H-fluorene-2,7-yl-alt-1,4-phenylene vinylene] (polymer-I) was synthesized by the modified Heck coupling reaction, and their EL characteristics were also investigated. Double layer polymer light-emitting display (PLED) with the configuration of ITO/PEDOT/polymer/Al devices show maximum brightness and luminous efficiency up to 3000 $cd/m^{2}$ at 30 V and 0.07 lm/W at 21 V, respectively.

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Synthesis and Photovoltaic Properties of Low Band Gap π-Cojugated Polymer Based on 4,7-Di-thiophen-2-yl-benzo[1,2,5]thiadiazole (4,7-Di-thiophen-2-yl-benzo[1,2,5]thiadiazole을 기본으로 한 고분자의 합성 및 광전변환 특성)

  • Shin, Woong;You, Hyeri;Park, Jeong Bae;Park, Sang Jun;Jeong, Mi Seon;Moon, Myung-Jun;Kim, Joo Hyun
    • Applied Chemistry for Engineering
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    • v.21 no.2
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    • pp.137-141
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    • 2010
  • Poly [4,7-Di-thiophen-2-yl-benzo(1,2,5)thiadiazole]-alt-1,4-bis(dodecyloxy)-2,5-divinylbenzene (PPVTBT) was synthesized by the Heck coupling reaction between 4,7-Di-thiophen-2-yl-benzo(1,2,5)thiadiazole and 1,4-bis(dodecyloxy)-2,5-divinylbenzene. The maximum absorption and band gap of PPVTBT were 550 nm and 1.74 eV, respectively. The HOMO and LUMO energy level of PPVTBT were -5.24 eV and -3.50 eV, respectively. The photovoltaic device based on the blend of PPVTBT and (6)-1-(3-(methoxycarbonyl)propyl)-{5}-1-phenyl[5,6]-$C_{61}$ (PCBM) (1 : 6 by weight ratio) was fabricated. The efficiency of device was 0.16%. The short circuit current density (Jsc), fill factor (FF) and open-circuit voltage (Voc) of the device was $0.74mA/cm^{2}$, 31% and 0.71 V, respectively, under AM 1.5 G and 1 sun condition ($100mA/cm^{2}$).

Synthesis and Photovoltaic Properties of Low Band Gap π-conjugated Polymers Based on 2-pyran-4-ylidene-malononitrile Derivatives (2-pyran-4-ylidene-malononitrile을 기본으로 하는 작은 Band Gap을 가지는 공중합체의 합성 및 광전변환 특성)

  • You, Hyeri;Shin, Woong;Park, Jeong Bae;Park, Sang Jun;Lim, Jun Heok;Kim, Joo Hyun
    • Applied Chemistry for Engineering
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    • v.20 no.3
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    • pp.273-278
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    • 2009
  • A series of poly[2-(2,6-dimethylpyran-4-ylidene)malononitrile-alt-1,4-bis(dodecyloxy)-2,5-divinylbenzene] (PM-PPV), poly[2-{2,6-Bis-[2-(5-bromothiophen-2-yl)-vinyl]-pyran-4-ylidene}-malononitrile-alt-1,4-bis(dodecyloxy)-2,5-divinylbenzene] (PMT-PPV) and poly[2-[2,6-Bis-(2-{4-[(4-bromophenyl)-phenylamino]-phenyl}-vinyl)-pyran-4-ylidene]-malononitrile-alt-1,4-bis(dodecyloxy)-2,5-divinylbenzene] (PMTPA-PPV) were synthesized by the Heck coupling reaction. The band gap of PM-PPV, PMT-PPV and PMTPA-PPV were 2.18 eV, 1.90 eV and 2.07 eV, respectively. The LUMO energy levels of PM-PPV, PMT-PPV and PMTPA-PPV were 3.65 eV, 3.54 eV and 3.62 eV, respectively and the HOMO energy levels of those were 5.83 eV, 5.61 eV and 5.52 eV, respectively. The photovoltaic devices based on the polymers was fabricated. The efficiency of the solar cells based on PM-PPV, PMT-PPV and PMTPA-PPV were 0.028%, 0.031% and 0.11%, respectively and the open circuit voltage (Voc) was 0.59 V~0.69 V under AM 1.5 G and 1 sun condition ($100mA/cm^2$).

Total Synthesis of ($\pm$)-Homoepibatidine

  • Kim, Yong-Hyun;Won, Do-Youn;Oh, Chang-Young;Lee, Kee-Young;Jeong, Jin-Hyun;Jung, Young-Hoon;Ham, Won-Hun
    • Archives of Pharmacal Research
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    • v.22 no.4
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    • pp.435-436
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    • 1999
  • Total synthesis of ($\pm$)-homoepibatidine (2), which contains the 8-azabicyclo[3.2.1] octane ring system, was achieved by using palladium-catalyzed Heck-type coupling reaction from 3.

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Synthesis and Light-Emitting Properties of Phenyl-Thiophene-Based Alternating Copolymers Synthesized by Heck Coupling Reaction

  • Shim, Hong-Ku;Taek Ahn;Lee, Hye-Young;Lee, Jeong-Ik
    • Macromolecular Research
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    • v.9 no.2
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    • pp.116-121
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    • 2001
  • A series of poly(1,4-phenylenevinylene-alt-3-alkyl-2,5-thienylenevinylene)s (alkyl = hexyl [PPV-alt-6-TV] and octyl (PPV-alt-8-TV] group) have been synthesized by the Heck coupling reaction. These polymers were characterized using $^1$H-NMR, FT-IR spectroscopy, and thermogravimetric analysis (TCA). They are solvent processible and have obviously copolymeric structure. The photophysical properties of the polymers were investigated using UV-visible and steady-state photoluminescence(PL) spectroscopy. We studied the change of light-emitting properties by incorporating the thiophene group into the PPV polymer backbone using alternating copolymer system. The properties of two synthesized polymers are very similar, but they exhibited apparent changes of light-emitting properties compared with other PPV backbone based polymers. The broad absorption bands from 350 to 570 nm are due to $\pi$-$\pi$* transitions of the polyconjugated systems. The absorption maxima of the two polymers were found at about 452 and 448 nm for PPV-alt-6-TV and PPV-alt-8-TV, respectively. The copolymers showed broad PL spectra between 550 and 700 nm without vibronic bands and PL emission maxima of PPV-alt-6-TV and PPV-alt-8-TV are about 620 and 605 nm, respectively. The copolymers exhibited the red emission (PPValt-6-TV), but more red shifted emissions are needed to obtain real red color.

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Photoluminescence and Electroluminescence of Carbazole-based Conjugated Dendritic Molecules

  • Cho, Min-Ju;Kim, Young-Min;Ju, Byeong-Kwon;Choi, Dong-Hoon
    • Journal of Information Display
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    • v.9 no.3
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    • pp.16-22
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    • 2008
  • A novel class of conjugated dendritic molecules bearing N-hexyl-substituted carbazoles as peripheral groups and various conjugative aromatic cores was synthesized through Heck coupling and the Horner-Emmons reaction. A multilayered structure of ITO/PEDOT:PSS (30 nm)/emitting material (50 nm)/BCP (10 nm)/$Alq_3$ (10 nm)/LiF (1 nm)/Al (100 nm) was employed to evaluate the synthesized dendritic materials. The electroluminescence spectrum of the multilayered device made of 3Cz predominantly exhibited blue emissions. Similar emissions were observed in the PL spectra of it's the device's thin film. The multilayered devices made of 3Cz, 3BCz, and 4BCz showed luminance values of 6,250 cd $m^{-2}$ at 24 V, 3,000 cd $m^{-2}$ at 25 V, and 1,970 cd $m^{-2}$ at 36 V, respectively. The smallest molecule, 3Cz, which bore three carbazole peripheral groups, exhibited a blue-like emission with CIE 1931 chromaticity coordinates of x = 0.17 and y = 0.21.