• Title, Summary, Keyword: cryptand

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NMR Investigation on the Intermolecular Hydrogen Bondings of the Macrocyclic Compounds Containing Nitrogen-Oxygen Donor Sets (질소-산소 주게 거대고리 화합물의 분자간 수소결합에 관한 NMR 연구)

  • Chang Ju Yoon;Jeong Kim;Si Joong Kim
    • Journal of the Korean Chemical Society
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    • v.29 no.2
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    • pp.151-157
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    • 1985
  • The intermolecular hydrogen bondings of 1,10-diaza-4,7,13,16-tetraoxacyclooctadecane(cryptand 22), 1,7-diaza-4,10,13-trioxacyclopentadecane(cryptand 21), 1,12,15-triaza-5,8-dioxa-3,4:9,10-dibenzocycloheptadecane ($N_3O_2$) and 1,12-diaza-5,8-dioxa-3,4:9,10-dibenzocyclotetradecane ($N_2O_2$) have been studied in chloroform solutions by $^1H$-nmr spectrometry at various temperatures. The molecules dimerize each other with the hydrogen bonds through N-H groups in the dilute solutions. The formation constants of the hydrogen bonds are in the order of cryptand 22 > cryptand 21 > $N_3O_2$ > $N_2O_2$. It appears that the constants depend on the molecular symmetry, the number of N-H group, and the localization of N-H groups in the molecule.

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Polarograms of Uranium(VI) and Rare Earth(III) Metal Complexes with Macrocyclic Ligands in Dimethylsulfoxide Solvent (디메틸술폭시드 용매중에서 거대고리리간드를 포함한 우라늄(VI)과 희토류(III) 금속 착물의 폴라로그램)

  • Hak Jin Jung;Oh Jin Jung;Chilnam Choi
    • Journal of the Korean Chemical Society
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    • v.32 no.3
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    • pp.233-242
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    • 1988
  • The uranium(VI) complexes with new unsaturated macrocyclic ligands of cryptand types and the neodymium(III) complexes with cryptand 222 and DBC ligands have been investigated polarographically in dimethylsulfoxide solvent. The reduction states, electron numbers involved in the reduction process, effects of the added acid on the polarograms of complexes, and the mechanisms of the reduction electrode reactions have been examined. The stability constants and mole-ratio of new complexes were also obtained by polarographic method. The reaction of ligands was controlled by the diffusion in the reduction with four electrons at a step, whereas the redox reaction with six electrons at three steps in $UO_2\;^{2+}$ complexes with macrocyclic ligands and the redox reaction with one electron at a step in $Nd^{3+}$ complexes with cryptand 222 and DBC have been observed. The imine ligands formed stable complexes with uranium(VI) above pH 7.0, and the neodymium(III) complexes with cryptand 222 and DBC ligands were stable above pH 4.0.

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Adsorption of Metal Ions on Cryptand Synthetic Resin (Cryptand 합성수지에 위한 금속 이온들의 흡착)

  • Lee Chi-Young;Kim Joon-Tae
    • Journal of environmental and Sanitary engineering
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    • v.20 no.4
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    • pp.38-44
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    • 2005
  • Cryptand resins were synthesized with 1-aza-15-crown-5 macrocyclic ligand attached to styrene divinylbenzene (DVB) copolymer with crosslink of $1\%,\;2\%,\;5\%\;and\;10\%$ by substitution reaction. The synthesis of these resins was confirmed by content of chlorine, element analysis, and IR-spectrum. The effects of pH, time, dielectric constant of solvent and crosslink on adsorption of uranium$(UO_2^{2+})$ ion were investigated. The uranium ion was showed fast adsorption on the resins above pH 3. The optimum equilibrium time for adsorption of metallic ions was about two hours. The adsorption selectivity determined in ethanol was in increasing order uranium$(UO_2^{2+})$ > zinc$(Zn^{2+})$ > samarium$(Sm^{3+})$ ion. The adsorption was in order of $1\%>2\%>5\%>10\%$ crosslink resin and adsorption of resin decreased in proportion to order of dielectric constant of solvents.

New Cryptand Complexes of Lanthanides(Ⅲ) and Dioxouranium(Ⅵ) Nitrates

  • Oh-Jin Jung;Chil-Nam Choi;Hak-Jin Jung
    • Bulletin of the Korean Chemical Society
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    • v.12 no.2
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    • pp.130-137
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    • 1991
  • The following new cryptand 221 complexes of lanthanides(Ⅲ) and dioxouranium(Ⅵ) nitrate have been synthesized: $(Ln(C_{16}H_{32}N_2O_5)(H_2O)_2(NO_3)_3\ and \((UO_2)_2(C_{16}H_{32}N_2O_5)(H_2O)_4(NO_3)_4$. These complexes have been identified by elemental analysis, moisture titration, conductivity measurements and various spectroscopic techniques. The proton and carbon-13 NMR as well as calorimetric measurements were used to study the interaction of cryptand 221 with La(Ⅲ), Pr(Ⅲ ), Ho(Ⅲ) and $UO_2(Ⅱ)$ ions in nonaqueous solvents. The bands of metal-oxygen atoms, metal-nitrogen atoms and O-U-O in the IR spectra shift upon complexation to lower frequencies, and the vibrational spectra ({\delta}NMN$) of metal-amide complexes in the crystalline state exhibit lattice vibrations below 300 $cm^{-1}$. The NMR spectra of the lanthanides(Ⅲ) and dioxouranium(Ⅵ) nitrate complexes in nonaqueous solvents are quite different, indicating that the ligand exists in different conformation, and also the $^1H$ and $^{13}C-NMR$ studies indicated that the nitrogen atom of the ring has greater affinity to metal ions than does the oxygen atom, and the planalities of the ring are lost by complexation with metal ions. Calorimetric measurements show that cryptand 221 forms more stable complexes with $La^{3+}$ and $Pr^{3+}$ ions than with $UO^{22+}$ ion, and $La^{3+}/Pr^{3+}$ and $UO^{22+}/Pr^{3+}$ selectivity depends on the solvents. These changes on the stabilities are dependent on the basicity of the ligand and the size of the metal ions. The absorption band (230-260 nm) of the complex which arises from the direct interaction of macrocyclic donor atoms with the metal ion is due to n-{\delta}*$ transition and also that (640-675 nm) of $UO^{22+}$-cryptand 221 complex, which arises from interaction between two-dioxouranium(Ⅵ) ions in being out of cavity of the ligand ring is due to d-d* transition.

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Adsorption Characteristic and Elution Behavior of Rare Earth Metals by Cryptand 22 Synthetic Resin (Cryptand 22 합성수지에 의한 희토류 금속들의 흡착특성과 용리행동)

  • 노기환;김준태
    • Journal of environmental and Sanitary engineering
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    • v.11 no.1
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    • pp.17-25
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    • 1996
  • Resins with cryptand 22 macrocyclic ligand attached to chloromethylated styrene-1,4-divinylbenzene by substitution reaction were prepared and the effect of pH, metal concentration and cross-linkage of the matrix on the adsorption for $UO_2^{2+}$, $Cd^{2+}$ and $Sm^{3+}$ was investigated. The metal ion was not adsorbed on the resins pH range below 3 but above pH 4 fast adsorption behavior was showed. The resin selectivity determined in ethanol matrix was in increasing order $UO_2^{2+}{\;}>Cd^{2+}{\;}Sm^{3+}$. In addition, these metal ion could be separated on the column packed with 1% crosslinked resin by pH 2.5 $HNO_3$ as an eluent.

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Chromatographic Behavior of Cryptand[2,2] Modified Resin on Metal Cations

  • Suh, Moo-Yul;Eom, Tae-Yoon;Suh, In-Suk;Kim, Si-Joong
    • Bulletin of the Korean Chemical Society
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    • v.8 no.5
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    • pp.366-372
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    • 1987
  • Cryptand[2,2] was grafted to low crosslinked styrene-divinylbenzene copolymer by substitution reaction with chloromethylated styrene-divinylbenzene copolymer. This resin was stable in concentrated acid and base, and showed a good resistance to heat. The pH, time, and concentration dependence of the adsorption of metal ions by this resin were studied. Studies on the chromatographic separation of lanthanides, $Cu^{2+}$ and $UO_2^{2+_2}$ were also carried out with various eluents. These studies demonstrate that this resin has the applicability to the preconcentration and separation of metal ions.

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Adsorption of Uranium(VI) Ion Utilizing Cryptand Ion Exchange Resin (Cryptand 이온교환 수지를 이용한 우라늄(VI) 이온의 흡착)

  • Park, Seong-Kyu;Kim, Joon-Tae
    • Analytical Science and Technology
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    • v.17 no.2
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    • pp.91-97
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    • 2004
  • Cryptand ion exchange resins were synthesized with 1-aza-15-crown-5 macrocyclic ligand attached to styrene divinylbenzene (DVB) copolymer with crosslink of 1%, 2%, 5% and 10% by substitution reaction. The synthesis of these resins was confirmed by content of chlorine, element analysis, and IR-spectrum. The effects of pH, time, dielectric constant of solvent and crosslink on adsorption of uranium ($UO{_2}^{2+}$) ion were investigated. The uranium ion was showed fast adsorption on the resins above pH 3. The optimum equilibrium time for adsorption of metallic ions was about two hours. The adsorption selectivity determined in ethanol was in increasing order uranium ($UO{_2}^{2+}$), magnesium ($Mg^{2+}$), neodymium ($Nd^{3+}$) ion. The adsorption was in order of 1%, 2%, 5%, and 10% crosslink resin and adsorption of resin decreased in proportion to order of dielectric constant of solvents.

Adsorption of Uranium Ion Utilizing OenNtn-Styrene-DVB Resin (OenNtn-스틸렌-DVB 수지를 이용한 우라늄(VI) 이온의 흡착)

  • 김준태;노기환;강영식
    • Journal of environmental and Sanitary engineering
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    • v.18 no.2
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    • pp.9-15
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    • 2003
  • Resins have been synthesized from chlormethyl styrene 1,4- divinylbenzene(DVB) with 1%, 4%, and 20%-crosslinked and macrocyclic ligand of cryptand type by copolymerization method and the adsorption of uranium(VI), nickel(II) and lutetium(III) ions have been investigated in various experimental conditions. The correlation between the adsorption characteristics of rare earths and transition metal on the resins and stability constants of complexes with macrocyclic ligand have been examined. The uranium ion was not adsorbed on the resins below pH 2.0, but the power of adsorption of uranium ion increased rapidly above pH 3.0. The adsorption power was in the order of 1%, 4% and 20%-crosslinked resin, but adsorptive characteristics of resins decreased in proportion to the order of dielectric constants of solvents.

Adsorption Characteristic of Mg(II), Al(III), Pb(II) Metal Ions on Cryptand Ion Exchange Resin from Water Fire Extinguishing Agent (물 소화약제로부터 Cryptand 이온교환수지의 Mg(II), Al(III) 및 Pb(II) 흡착특성)

  • Kim, Joon-Tae;Kim, Kwan-Chun
    • Journal of environmental and Sanitary engineering
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    • v.23 no.1
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    • pp.57-65
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    • 2008
  • Resins were synthesized with 1-aza-15-crown-5 macrocyclic ligand attached to styrene(dangerous matter) divinylbenzene(DVB) copolymer with crosslink of 1, 2, 6 and 15% by substitution reaction. The synthesis of these resins was confirmed by content of chlorine, element analysis, and IR-spectrum. The effects of pH, time and crosslink on adsorption of metal ion from water fire extinguishing agent by the synthetic resin adsorbent were investigated. The metal ion was showed fast adsorption on the resins above pH 3. The optimum equilibrium time for adsorption of metallic ions was about two hours. The adsorption selectivity determined in water was in increasing order of $Mg^{2+}>Al^{3+}>Pb^{2+}$. The adsorption was in the order of 1, 2, 6, and 15% crosslink resin.