• 제목/요약/키워드: Reductive

검색결과 472건 처리시간 0.025초

Electrochemical Characterization of Electric Double Layer Capacitors Assembled with Pyrrolidinium-Based Ionic Liquid Electrolytes

  • Cho, Jinhyun;Shin, Won-Kyung;Kim, Dong-Won;Kim, Young Rae;Lee, Byung Jun;Kim, Sang-Gil
    • Journal of Electrochemical Science and Technology
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    • 제7권3호
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    • pp.199-205
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    • 2016

  • We present the electrochemical performance of electric double layer capacitors (EDLCs) assembled with pyrrolidinium (Pyr)-based ionic liquid electrolytes at 55 ℃. Cations with various alkyl chain lengths were employed in Pyr-based ionic liquids to investigate the effect of cation structure on the cycling stability of EDLCs. The EDLCs exhibited initial specific capacitances ranging from 122.4 to 131.6 F g−1 based on activated carbon material at 55 ℃. Cycling data and XPS results demonstrate that Pyr-based ionic liquid with longer alkyl chain is more effective for enhancing the cycling stability of EDLC by suppressing the reductive decomposition of pyrrolidinium cations during cycling at high temperatures.

  • https://doi.org/10.5229/JECST.2016.7.3.199 인용 PDF KSCI KPUBS HTML

Preparation of Nanosized Gold Particles by Microwave Irradiation and Kinetics Study for Reduction of 4-Nitroaniline under Various Conditions

  • Kim, Jae Jin;Ko, Weon Bae
    • Elastomers and Composites
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    • 제50권4호
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    • pp.274-278
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    • 2015

  • Nanosized gold particles were synthesized by microwave irradiation in a mixture composed of potassium tetrachloroaurate(III) n-hydrate, sodium citrate dihydrate and Tween 20. The synthesized gold particles were characterized by UV-vis spectrophotometer, scanning electron microscopy, and X-ray diffraction techniques. Using UV-vis spectroscopy, it was confirmed that gold nanoparticles act as a catalyst in the reduction of 4-nitroaniline with sodium borohydride to form 1,4-diaminobenzene. Additionally, we studied the kinetics of this reductive reaction in the presence of these gold nanoparticles under various conditions.

  • https://doi.org/10.7473/EC.2015.50.4.274 인용 PDF KSCI

A Stereoselective Synthesis of 1 $\beta$-Aminocarbapenems.

  • 서경재;이태호;이연영
    • Bulletin of the Korean Chemical Society
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    • 제22권6호
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    • pp.553-558
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    • 2001

  • A stereoselective synthesis of $1\beta-aminocarbapenems$ (11a-c) starting from-4-acetoxy-2-axetidinone derivative 4 is described. 4-Acetoxy-2-azetidinone derivative (4) was reacted with lithium enolate of benzophenone limine of glycine phenyl ester (5f) to give alkylated product (R)-6f in good yield with high diastereoselectivity. The alkylated procudt (R)-6f was transformed to thioesters (7a-c) by transesterification with thiols, Thioesters (7a-c) were converted to their oxalimides (8a-c), followed by the phosphite-mediated reductive cyclization to give carbapenems (9a-c). Removal of all protecting groups of carbapenems (9a-c) afforded $1\beta-aminocarbapenems$ (11a-c).

  • https://doi.org/10.5012/bkcs.2001.22.6.553 인용 PDF

5-(p-톨루오일)-1-메틸피롤-2-아세트산의 합성 (Synthesis of 5-(p-Toluoyl)-1-Methylpyrrole-2-Acetic Acid [Tolmetin])

  • 최홍대;마정주
    • 약학회지
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    • 제36권4호
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    • pp.341-344
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    • 1992

  • A facile method for tolmetin, which is a potent antiinflammatory agent, is described. Friedel-Crafts reaction of 1-methylpyrrole with ethyl ${\alpha}-chloro-{\alpha}-(methylthio)acetate$ (1) gave ethyl ${\alpha}-methylthio$-1-methyl-2-pyrroleacetate (4), which was readily converted into ethyl 1-methyl-2-pyrroleacetate (5) by reductive desulfurization with zinc dust in acetic acid. Tolmetin was synthesized by Friedel-Crafts acylation of (5) with p-toluoyl chloride, followed by hydrolysis of the resultant ethyl 5-(p-toluoyl)-1-methylpyrrole-2-acetate (6).

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