• Title/Summary/Keyword: chemical reagents

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Synthesis and Catalytic Properties of Imidazole-Functionalized Poly(propylene imine)Dendrimers

  • Baker, Lane A.;Sun, Li;Crooks, Richard M.
    • Bulletin of the Korean Chemical Society
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    • v.23 no.5
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    • pp.647-654
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    • 2002
  • The synthesis and characterization of third- and fifth-generation poly(propylene imine) dendrimers terminated with imidazole moieties is reported. Functionalization was achieved using simple peptide coupling reagents. These materials were characte rized by MALDI-MS, NMR, and titration. The use of these endgroup-functionalized dendrimers as catalysts for the hydrolysis of 2,4-dinitrophenyl acetate is described. Molecular simulations provide a basis for interpreting the catalytic data.

Synthesis of Dienamides via the Reaction of Nitrile with Allylindium Reagents and Intramolecular Acyl Group Quenching Cascade

  • Kim, Sung-Hwan;Kim, Yu-Mi;Kim, Jae-Nyoung
    • Bulletin of the Korean Chemical Society
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    • v.31 no.8
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    • pp.2351-2356
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    • 2010
  • Various dienamide derivatives were synthesized in reasonable yields from benzonitriles having an amide moiety at the ortho-position, via the sequential (i) In-mediated allylation of nitrile moiety to form an imine intermediate, (ii) intramolecular quenching of an acyl group by the imine intermediate, and (iii) a proton transfer to dienamide.

A Study on the Identification of Phenol Production by GC/MS under Chemical Treatment of Industrial Wastewater (화학적 폐수처리 중 GC/MS에 의한 폐놀생성 규명에 관한 연구)

  • 박선구;고오석;신대윤
    • Journal of Environmental Science International
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    • v.9 no.1
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    • pp.89-93
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    • 2000
  • Twenty organic chemical substances(Table 2) were isolated from untreated wastewater, as well as treated wastewater, collected at 76 companys of 9 industry group located in the basin of Youngsan River. Those organic compounds were analyzed by Gas Chromatography/Mass Spectrometry(GC/MS) and confirmed through comparison with each standard reagents. Phenol, which was not detected in the raw wastewater, was identified in the effluent of treatment facility, indicating that phenol is generated from isopropylbenzene of plant wastewater.

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On increasing the homogeneity of the properties of epitaxial layers grown from the gas phase, taking into account natural convection and changes in the rate of chemical interaction between materials

  • Pankratov, E.L.
    • Advances in materials Research
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    • v.9 no.2
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    • pp.155-170
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    • 2020
  • In this paper, using the recently introduced analytical approach for the analysis of mass and heat transfer during film growth in reactors for epitaxy from the gas phase, these processes are analyzed taking into account natural convection and the possibility of changing the rate of chemical interaction between reagents. As a result of the analysis, the conditions under which the homogeneity of the grown epitaxial layers increases with a change in the values of the parameters of the growth process are formulated.

Mechanism for Chemiluminescent Reactions of Bis(2,4,6-trichlorophenyl)oxalate, Hydrogen Peroxide and Fluorescent Aromatic Hydrocarbons

  • Song Hyung-Soo;Shin Hyung Seon;Kim Kang-Jin
    • Bulletin of the Korean Chemical Society
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    • v.9 no.1
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    • pp.17-21
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    • 1988
  • A mechanistic study on the chemiluminescence resulting from the reaction between bis(2,4,6-trichlorophenyl)oxalate(TCPO) and hydrogen peroxide in the presence of fluorescent polycyclic aromatic hydrocarbons in a viscous phthalate medium has been conducted. The rate determining step, decay rate constants, and relative quantum efficiencies yielded by varying the concentration of reagents generally support an existing mechanism. However, a reaction between TCPO and sodium salicylate was not observed.

Thexylalkoxyborane as Hydroborating Agent for Alkenes and Alkynes

  • 차진순;서원우;김종미;권오운
    • Bulletin of the Korean Chemical Society
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    • v.17 no.10
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    • pp.892-899
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    • 1996
  • In order to elucidate the effect of alkoxy substituent in thexylborane and hence establish their usefulness as hydroborating agent, reactions of alkenes and alkynes with thexylalkoxyborane (ThxBHOR; R=Et, i-Pr, i-Bu, sec-Bu, t-Bu, Ph) were investigated in detail. The reagents readily hydroborated alkenes and alkynes of various structural types at 25 ℃ in excellent regioselectivity. The selectivity increases consistently with increasing steric size of alkoxy substituent. Especially, the selectivity achieved by the sec-butoxy derivative is comparable to that previously achieved by thexylhaloborane-methyl sulfide (ThxBHX·SMe2), the most selective hydroborating agent known.

Lithium Trimethylalkynylaluminate, A New Chemoselective Alkynylating Agent

  • 안진희;심태보;정명주;윤능민
    • Bulletin of the Korean Chemical Society
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    • v.17 no.4
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    • pp.380-384
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    • 1996
  • Lithium trimethylalkynylaluminates, prepared conveniently by reacting trimethylaluminum with lithium alkynide, readily react with aldehydes and ketones to give the corresponding propargyl alcohols in 70-95% yields. The reaction is highly chemoselective; thus many other functional groups such as amides, nitriles, epoxides and halogen compounds are inert under the reaction conditions. The reagents also show an excellent 1,2-regiospecificity in the reactions with cyclic or acyclic α,β-unsaturated carbonyl compounds.

Theoretical Study on the Regioselectivity of Tetrazolylimines with Alkyl Grignard Reagents

  • 유성은;공영대;김수경
    • Bulletin of the Korean Chemical Society
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    • v.20 no.4
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    • pp.441-444
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    • 1999
  • The alkyl Grignard addition reaction on 1-benzyltetrazolylimine proceeds to give N-alkylated products (azophilic addition) and, in contrast, the same reaction on 2-benzyltetrazolylimine produced predominantly C-alkylated products (carbophilic addition). In this report we described theoretical explanations for this experimental finding on the basis of the frontier molecular orbitals and the electrostatic nature of the reactants and the reaction intermediates.