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Daejeon, South Korea

Kim J.-G.,Hanwha Chemical Randnter | Jang D.O.,Yonsei University
Synlett | Year: 2010

Various carboxylic acids were converted into acyl fluorides in excellent yields by treatment with trichloroacetonitrile, triphenylphosphine, and TBAF(t-BuOH)4 at room temperature. The reaction was applicable to the preparation of acid-sensitive amino acid fluorides without deprotection or rearrangement © 2010 Georg Thieme Verlag Stuttgart New York.

Kim J.-G.,Hanwha Chemical Randnter | Jang D.O.,Yonsei University
Synlett | Year: 2010

We have developed a simple, mild method for N-formylation of a wide variety of amines in the presence of indium metal as a catalyst under solvent-free conditions. This reaction is applicable to the chemoselective N-formylation of amino groups and -amino acid esters without epimerization. © Georg Thieme Verlag Stuttgart.

Nam H.-S.,Hanwha Chemical Randnter | Nam H.-S.,KAIST | Jang K.-S.,Korea Research Institute of Chemical Technology | Ko J.M.,Hanbat National University | And 2 more authors.
Electrochimica Acta | Year: 2011

The nanoporous RuO2·3.38H2O was synthesized with a surfactant template using sodium dodecyl sulfate. The surface area of the material amounted to 220 m2 g-1 while the maximum specific capacitance obtained was 870 Fg-1 at a scan rate of 10 mV s-1. The specific capacitance of nanoporous RuO2·3. 38H2O electrode exhibits enhancement, compared with other porous RuO2 materials synthesized by different methods. The nanoporous RuO2·3.38H2O is a very promising material for high performance capacitance. © 2011 Elsevier Ltd. All rights reserved.

Kim J.-G.,Hanwha Chemical Randnter | Mishra M.K.,Yonsei University | Jang D.O.,Yonsei University
Tetrahedron Letters | Year: 2012

A mild and efficient method to synthesize sterically hindered ketones from aldehydes via O-silyl oximes was developed. Treatment of O-triphenylsilylated oximes with alkyl iodides in the presence of triethyl borane afforded the corresponding ketones. © 2012 Elsevier Ltd. All rights reserved.

Yu H.-C.,Yonsei University | Vijay Kumar S.,Yonsei University | Cho S.-Y.,Yonsei University | Kudo K.,University of Tokyo | And 5 more authors.
Journal of Nanoscience and Nanotechnology | Year: 2011

Fully aliphatic polyimides (APIs) were prepared from rel-(1′R, 3S5′S)-spiro[furan-3(2H),6′-[3]oxabicyclo[3.2.1]octane]-2,2′, 4′,5(4H)-tv e etrone (D An) as unsymmetrical spiro dianhydride, and either cis-trans-1,4-diaminocyclohexane (mix-DACH) or trans-1,4-diaminocyclohexane (trans-DACH) as diamine. Structure of all prepared monomers and polymers was confirmed via 1H-NMR and FT-IR. The solubility, optical transparency, and thermal properties of the full APIs were investigated. The solubility and decomposition temperature of the full APIs were found to be correlated with their intermolecular regularity confirmed via wide-angle X-ray diffraction (WAXD). Triblock copoly-imides were synthesized through the incorporation of a thermally labile polymer, poly(propylene glycol) (PPG), into the full APIs, and their thermal properties were studied via thermogravimet-ric analysis (TGA). Nanoporous thin films of the full APIs were prepared via thermolysis of the labile block in the copolyimide films. Phase separation and nanopore formation in the copolymer films were confirmed via atomic force microscopy (AFM) and scanning electron microscopy (SEM), respectively. Nanoporous pores were successfully prepared inside the films. Copyright © 2011 American Scientific Publishers All rights reserved.

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