• Title/Summary/Keyword: 2-diamine

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Polymeric Lead(II)-selective Electrode Based on N,N'-Bis-thiophen-2-ylmethylene-pyridine-2,6-diamine as an Ion Carrier

  • Kim, Hee-Cheol;Lee, Hyo-Kyoung;Choi, A-Young;Jeon, Seung-Won
    • Bulletin of the Korean Chemical Society
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    • v.28 no.4
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    • pp.538-542
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    • 2007
  • Polymeric electrodes for lead ion based on N,N'-bis-thiophen-2-ylmethylene-pyridine-2,6-diamine as an ion carrier were prepared. The membrane electrode (m-3) containing o-NPOE as a plasticizer and 50 mol% additive of ionophore gives an excellent Nernstian response (29.59 mV/decade) and the limit of detection of ?log a (M) = 5.74 to Pb2+ in Pb(NO3)2 solution at room temperature. The prepared electrode provided good sensitivity and outstanding selectivity and response for Pb2+ over a wide variety of other metal ions in pH 7.0 buffer solutions. The good sensitivity and selectivity towards lead ion are attributed to the strong complexation of lead ion to N,N'-bis-thiophen-2-ylmethylene-pyridine-2,6-diamine which has geometrically the proper cavity to coordinate to the ligand.

Synthesis and Characterization of Soluble Co-polyimides for Biogas Purification (바이오가스 정제용 용해성 폴리이미드 공중합체의 합성과 특성분석)

  • Shin, So Ra;Han, Sang Hoon;Kim, Jeong-Hoon
    • Membrane Journal
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    • v.25 no.3
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    • pp.231-238
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    • 2015
  • Co-polyimide membranes were prepared by two-step polymerization using semi-alicyclic 5-(2,5-dioxotetrahydrofuryl)-3-methyl-cyclohexene-1,2-dicarboxylic anhydride (DOCDA) with five diamines such as 2,5-dimethyl-1,4-phenylene diamine (2M), 2,4,6-trimethyl-1,3-phenylene diamine (3M), 1,5-naphthalene diamine (NDA), 4,4-diaminodiphenyl methane (MDA), 4,4'-diaminodiphenyl ether (ODA). Synthesized co-polyimides were characterized by FT-IR, viscosity, solubility, DSC, TGA and gas permeation properties, compared with 6FDA-based co-polyimides. All co-polyimides had the intrinsic viscosity of 0.32~0.58 and excellent solubility in various solvents. DOCDA-based co-polyimides had thermal stability over $400^{\circ}C$ although those were lower than 6FDA-based co-polyimides. Gas permeabilities of the copolyimide membranes were measured for $CO_2$ and $CH_4$ at room temperature and presented the trade-off relationship.

Enantioseparation of Racemic 1,1'Binaphthyl-2,2'diamine by Preparative Liquid Chromatography

  • Ryoo, Jae-Jeong;Kwon, Woo-Jeong;Kim, Tae-Hyuk;Lee, Kwang-Pill;Choi, Seong-Ho
    • Bulletin of the Korean Chemical Society
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    • v.25 no.9
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    • pp.1336-1340
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    • 2004
  • The same kind of chiral stationary phase with a commercialized chiral column was used to make preparative chiral columns and was applied to resolve racemic N-acetyl-1-naphthylethylamide (3) by preparative liquid chromatography. An improved chromatographic condition to resolve racemic 3 on the CSP was examined by changing flow rate and kind of the mobile phase and the sample injection volume. The optimized separation conditions were applied to resolve racemic 1,1'-Binaphthyl-2,2'-diamine(4).

Highly Copper(II)-selective PVC Membrane Based on a Schiff Base Complex of N,N'-Bis-pyridin-2-ylmethylene-naphthalene-1,8-diamine as an Ionophore

  • Jeong, Dae-Cheol;Lee, Hyo-Kyoung;Jeon, Seung-Won
    • Bulletin of the Korean Chemical Society
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    • v.27 no.10
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    • pp.1593-1596
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    • 2006
  • The polymeric membrane electrodes based on N,N'-bis-pyridin-2-ylmethylene-naphthalene-1,8-diamine as an ion carrier were prepared and tested for the copper-ion selective electrode. The membrane has a linear dynamic range between $10^{-6}$ and $10^{-2}$ M with a Nernstian slope of 29.6 mV per decade, and its detection limit was $10^{-5.62}$M. The potentiometric response is independent of the pH range of 3-5. The proposed electrode showed good selectivity and response for $Cu^{2+}$ over a wide variety of other metal ions in pH 4.0 buffer solutions.

Synthesis and Characterization of Urethane Group Containing Benzoquinone /Diamine Polymers (우레탄기를 포함하는 벤조퀴논/디아민 중합체의 합성과 특성분석)

  • Kim, Jun-Ho;Noh, Si-Tae;Kim, Dong-Kook;Lee, Chi-Gyu
    • Applied Chemistry for Engineering
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    • v.4 no.4
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    • pp.814-822
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    • 1993
  • To improve the solubility and adhesion strength of diamine-quinone polymers, urethane group was introduced into the polymer backbone. Urethane group containing polymeric diamines(UDA) were prepared firstly by the decarboxylation of the NCO group in NCO terminated prepolymer obtained from the reaction of MDI and 1.6-hexandiol. The reaction mole ratio of NCO/OH was changed from 1.2 to 2.1 to increase the molecular weight of diamine. From the addition reaction of UDA and p-benzoquinone in THF or DMSO solvent, five kinds of urethane group containing diamine/quinone polymers(PUAQ) were prepared according to the diamine used. IR, NMR, UV-visible spectroscopy and GPC were used to characterize the molecular structure and molecular weight of UDAs and PUAQs. Thermal analysis of polymer by DSC and TGA were carried out according to the molecular weight differency. Also solubility test of UDA and PUAQ with 10 different solvents were carried out to predict the coacting property of the polymers.

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Stereoselective Ligand Exchange Reaction of trans-dichlorocobalt(III) complex contained SS-epm and racemi propane-1,2-diamine (SS-epm이 배위된 trans-dichlorocobalt(III) 착물과 라세미 propane-1,2-diamine과의 입체선택적 리간드 치환반응)

  • Kim, Dong-Yeub
    • Journal of the Korean Society of Industry Convergence
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    • v.3 no.1
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    • pp.77-82
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    • 2000
  • The stereoselective ligand exchange reaction of trans-$[Co(SS-epm)Cl_2]^+$ and racemic propane-1,2-diamine (rac-pn) produces the complex that is identified as $[CO(N)_6]^{3+}$ type of $[Co(SS-epm)(pn)]^{3+}$ by absorption spectrum. It is conceivable that the reaction mechanism involves substitution and isomerization. The calculated and experimentally determined ratios of the complexed enantiomeric substrates at equilibrium were as follows: $[Co(SS-epm)(pn)]^{3+}$,calcd 32 % / 68 %, exptl 19 % / 81 % R-pn / S-pn. It has been shown that the employment of molecular mechanics calculations as a predictive tool may lead to the design of chiral complexes that may be applied to the separation of racemic mixtures of simple bidentate ligands.

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Study on the Coordination Polymers of Metal (II) Ions with 2,5-Diamine 1,4-Dihydroxybenzene (2,5-Diamine 1,4-Dihydroxybenzene과 금속 (II) 이온이 만드는 Coordination Polymer에 관하여)

  • Joon Suk Oh;Kyun Ok Cho
    • Journal of the Korean Chemical Society
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    • v.13 no.4
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    • pp.309-312
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    • 1969
  • A series of metal ion-2, 5-diamine 1, 4-dihydroxybenzene polymers containing copper(II), nickel(II) or cobalt (II) have been prepared. The structure was postulated on the basis of elementary analysis of polymers. It was found that copper polymer is most likely the coordination polymers by X-ray powder pattern studies. The thermal stability of the polymers was also studied by a simple method, utilizing a thermogravimetric balance. The order of thermal stabilities is Cu(II) > Ni(II) > Co(II). The polymers start to decompose at a relatively low temperature.

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Enantioselective Hydrosilylation of Imines Catalyzed by Diamine-Zinc Complexes

  • Park, Bu-Mahn;Feng, Xinhui;Yun, Jae-Sook
    • Bulletin of the Korean Chemical Society
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    • v.32 no.spc8
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    • pp.2960-2964
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    • 2011
  • The efficient asymmetric hydrosilylation of imines in the presence of polymethylhydrosiloxane has been investigated by screening chiral diamine-zinc complexes. A series of chiral diamine ligands were prepared from optically pure 1,2-diphenyl-1,2-ethanediamine and screened for effectiveness. N-Benzylic substituents were required for high enantioselectivity; ligands with bulky groups or extra coordinating groups such as OH and S lowered the catalytic activity. The level of asymmetric induction was usually in >90% ee range for aromatic imine substrates. A linear correlation between the ee of the ligand and that of the product was observed, indicating the presence of a 1:1 ratio of ligand to metal coordination in the active catalytic complex.

Conformational Change of Optically Active [Co(acac)$_2$(diamine)]$^+$ Complexes in Some Organic Solvents

  • Kim, Yang;Oh Chang-Eon
    • Bulletin of the Korean Chemical Society
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    • v.8 no.6
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    • pp.441-444
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    • 1987
  • The circular dichroism(CD) spectra of the optically active [$Co(acac)_2(diamine)]^+$ complexes were measured in the several protic and aprotic solvents, where acac = acetylacetonate anion and diamine = ethylenediamine and trimethylenediamine. The degree of the CD variation in protic solvents was enhanced as the dielectric constant decreases except n-butanol and benzylalcohol. And the degree of the CD variation in aprotic solvents was roughly increased as both dipole moment and dielectric constant decrease except aromatic solvents and the solvents having no dipole moment. It was deduced that the CD variations of the complexes have been due to the conformational change of acetylacetonate ligands coordinated to Co(III) ion.