• Polymer(Korea)
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• v.39 no.2
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• pp.300-310
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• 2015

In this study, we modified silica nanoparticles with N-[3-(trimethoxysilyl)propyl]ethylenediamine (TPED) silane coupling agent, which has one primary and one secondary amino groups in a molecule, to introduce amino groups on the silica surface. After modification of silica, we used 3-(acryloyloxy)-2-hydroxypropyl methacrylate (AHM) to introduce methacrylate groups by Michael addition reaction. We found about 30% of N-H groups on the TPED modified silica surface reacted with acrylate groups of AHM compared to about 85% of reaction between N-H groups of pure TPED with acrylate groups of pure AHM. This lower degree of Michael addition reaction for heterogeneous reaction between N-H groups on the solid TPED modified silica and liquid AHM compared to homogeneous reaction between pure liquid TPED and pure liquid AHM may be caused by lower mobility of grafted amino groups of TPED moiety and higher steric hindrance caused by solid silica particles.

• Bulletin of the Korean Chemical Society
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• v.34 no.5
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• pp.1563-1566
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• 2013

• Archives of Pharmacal Research
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• v.24 no.1
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• pp.27-34
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• 2001

A series of 2-methylbenzimidazole incorporated to different heterocycles through ethyl or carbamoylethyl groups at position 1 of benzimidazole were synthesized. Also 3-(2-methylbenzimidazol-1-yl)propanoic acid hydrazide incorporated with semicarbazides and thiosemicarbazides were prepared. Moreover, the triazole 5e underwent Michael addition and alkylation reaction. Some of the newly synthesized compounds showed considerable antimicrobial activity against gram positive, negative bacteria and yeast.

• Bulletin of the Korean Chemical Society
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• v.35 no.1
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• pp.98-102
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• 2014

The organocatalytic enantioselective Michael addition reaction promoted by chiral binaphthyl-modified squaramide catalyst have been developed, allowing facile synthesis of the corresponding chiral 2-amino-4H-chromenes derivatives with excellent enantioselectivity (up to 99% ee). The method reported represents a practical entry for the preparation of chiral 2-amino-4H-chromenes derivatives.

• Bulletin of the Korean Chemical Society
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• v.35 no.10
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• pp.2950-2954
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• 2014

A series of bis and tris-indolylketones and meridianin alkaloids are prepared by one pot Michael reaction of indole and ketene S,S-acetals under solvent-free condition using mild Lewis acid $InCl_3$.

• Bulletin of the Korean Chemical Society
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• v.26 no.3
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• pp.477-480
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• 2005

• Bulletin of the Korean Chemical Society
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• v.32 no.1
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• pp.311-314
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• 2011

• Bulletin of the Korean Chemical Society
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• v.24 no.10
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• pp.1425-1426
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• 2003

• Journal of the Korean Society of Propulsion Engineers
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• v.2 no.3
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• pp.47-53
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• 1998

Using Michael Reaction, commercially available 3-aminopropyltrimethoxysilane and N-[3-(trimethoxysilyl)propuyl]ethylenediamine were reacted with various Michael acceptors, ethyl acrylate, acrylonitrile, acrylamide, 2-cyanoethyl acrylate, 2-hydroxyethyl acrylate and 3-(trimethoxysilyl)propylmethacrylate, to the new aminosilanes. All compounds which are [3-(N-2-carboethoxyethyl)aminopropyl]triethoxysilane, [3-(N-2-cyanoethyl)aminopropyl]triethoxysilane, [3-(N-di-2-car-boethoxyethyl)aminopropyl]triethoxysilane, [3-N-di-cyanoethyl) aminopropyl]triethoxysilane, [3-(N-2-cyanoethoxypropionyl)aminopropyl]triethoxysilane, [3-(N-di-2-cyanoethoxypropionyl)aminopropyl]triethoxysilane, [3-(N-di-2-hydroxyethoxy propionyl)aminopropyl]triethoxysilane, [3-(N-2-amidoethyl)aminopropyl]triethoxysil-ane,｛3-[N-(N-di-2-cyanoethyl)ethyl]aminopropyl｝triethoxysilane and ｛3-[N-(3-trimethoxysilylpropyl)-2-methylpropionyl]aminopropyl｝triethoxysilane were succes-sfully prepared in 35-70% yields and which were identified with $^1{H}$-NMR and FT-IR spectroscopy.

• Polymer(Korea)
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• v.36 no.6
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• pp.822-830
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• 2012

We used dipodal type bis[3-(trimethoxysilyl)propyl]amine (BTMA) silane coupling agent to modify silica nanoparticles to introduce secondary amino groups on the silica surface. These N-H groups were reacted with three different molecular weights (M.W. = 258, 575, and 700) of poly(ethylene glycol) diacrylates to introduce different attached layer thicknesses on the silica surface by Michael addition reaction. After Michael addition reaction, we used several analytical techniques such as fourier transform infrared spectroscopy (FTIR), elemental analysis (EA) and solid state $^{13}C$ cross-polarization magic angle spinning (CP/MAS) nuclear magnetic resonance spectroscopy to characterize introduced structures. We found almost complete Michael addition reaction of both two acrylate groups of PDGDA with N-H groups of BTMA modified silica to form ${\beta}$-amino acid esters. Between equimolar ratio of pure BTMA and pure PEGDA reaction, only one acrylate group of two acrylate groups of PEGDA reacted with N-H groups of pure BTMA to form ${\beta}$-amino acid ester and the other remaining acrylate group can be used to form a polymer later.