• Bulletin of the Korean Chemical Society
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• v.23 no.8
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• pp.1062-1066
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• 2002

The complexes [Ni(L)(INT)2]${\cdot}$5H2O (1) and [Cu(L)(H2O)](Cl)(INT)${\cdot}$3H2O (2) (L = 3,14-dimethyl-2,6,13,17-tetraazatricyclo[14,4,01.18 ,07.12 ]docosane, INT = isonicotinate) have been prepared and characterized by X-ray crystallography, electronic absorption, and cyclic voltammetry. The crystal structure of 1 reveals an axially elongated octahedral geometry with two axial isonicotinate ligands. The electronic spectra, magnetic moment, and redox potentials of 1 also show a high-spin octahedral geometry. However, 2 shows that the coordination environment around the copper atom is a distorted square-pyramid with an axial water molecule. The spectra and electrochemical behaviors of 2 are also discussed.

• Bulletin of the Korean Chemical Society
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• v.25 no.12
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• pp.1757-1763
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• 2004

A new series of nickel(II), cobalt(II)/(III) and copper(II) complexes of 14, 15 and 16-membered of macrocyclic ligands have been prepared and characterized by elemental analyses, IR, UV-VIS and $^1H-NMR$ spectra, magnetic susceptibilities, conductivities, DTA and ESR measurements. Molar conductances in DMF solution indicate that, the complexes are nonelectrolytes except (9-12) complexes. The electronic spectra show that, all complexes are square planar or distorted octahedral geometry. The ESR spectra of solid complexes (4), (8) and (11) show square planar of axial type symmetry $(d_{x2-y2})$ with considerable covalent bond character. However, complex (12) shows a spectrum of octahedral geometry with $d_{z2}$ ground state. Complex (12) shows exploitation in reducing the amount of electron adducts formed in DNA during irradiation with low radiation products.

• Journal of Integrative Natural Science
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• v.6 no.2
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• pp.104-110
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• 2013

1-Aza-12-crown-4 macrocyclic ligand was combined with styrene (2th petroleum in 4th class hazardous materials) divinylbenzene copolymer having 1%, 2%, 3%, and 6% crosslinks by a substitution reaction, in order to synthesize resin. These synthetic resins were confirmed by chlorine content, elementary analysis and IR-spectrum. As the results of the effects of pH, equilibrium arrival time, crosslink of synthetic resin, and dielectric constant of a solvent on uranium ion adsorption for resin adsorbent, the uranium ion showed high adsorption at pH 3 or over and adsorption equilibrium of uranium ion was about 2 hours. In addition, adsorption selectivity for the resin in methanol solvent was the order of uranium ($UO_2{^{2+}}$) > iron ($Fe^{3+}$) > lutetium ($Lu^{3+}$) ions, adsorbability of the uranium ion was in the crosslinks order of 1%, 2%, 3%, and 6% was increased with the lower dielectric constant.

• Bulletin of the Korean Chemical Society
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• v.19 no.7
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• pp.754-760
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• 1998

It was found that the adsorption of a cobalt(III) complex with a macrocyclic ligand, C-meso-5,7,7,12,14,14-hexamethyl-1,4,8,11-tetraazacyclotetradecane (hmc), was induced on a glassy carbon electrode by heavily oxidizing the electrode surface. Adsorption properties are discussed. The glassy carbon electrode with the adsorbed complex was employed to see the catalytic activities for the electro-reduction of O2. In the presence of oxygen, reduction of (hmc)Co3+ showed two cathodic waves in cyclic voltammetry. Compared to the edge plane graphite electrode at which two cathodic waves were also observed in a previous study, catalytic reduction of O2 occurred in the potential region of the first wave while it happened in the second wave region with the other electrode. A rotating disk electrode after the same treatment was employed to study the mechanism of the O2 reduction and two-electron reduction of O2 was observed. The difference from the previous results was explained by the different reactivity of the (hmc)CoOOH2+ intermediate, which is produced after the two electron reduction of (hmc)Co3+ in the presence of O2.

• Bulletin of the Korean Chemical Society
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• v.12 no.4
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• pp.368-370
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• 1991

The electrochemical behavior and the complex formation between N$i^{2+}$ and 1,7-diazs-15-crown-5 and 1,10-diaza-18-crown-6 in acetonitrile solution have been studied by DC polarography, differential puke polarography and cyclic voltammetry. Nickel(Ⅱ) complexes gave a single well-defined wave. The formation constants of their complexes were 1$0^{4.89} and 10^{3.86}$, respectively. Nickel(Ⅱ) ion was found to form complexes of 1-to-1 composition with 1,7-diaza-15-crown-5 and 1,10-diaza-18-crown-6. In addition, reduction steps were irreversible and the reduction current were diffusion controlled. The electrochemical reduction mechanism of Ni(Ⅱ)-macrocyclic diaza-crown complexes in acetonitrile solution is estimated.

• Bulletin of the Korean Chemical Society
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• v.12 no.5
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• pp.483-487
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• 1991

The tetraaza macrocyclic ligand 3,14-dimethyl-2,6,13,17-tetraazatricyclo $[14,4,0^{1.18} ,0^{7.12}]$docosa-2,12-diene(B), that contains two cyclohexane rings, has been prepared as its dihydroperchlorate salt by the nontemplate condensation of methyl vinyl ketone with 1,2-diaminocyclohexane and perchloric acid. Reduction of B with sodium borohydride produces 3,14-dimethyl-2,6,13,17-tetraazatricyclo$[14,4,0^{1.18},0^{7.12}]$docosane(C). Square planar Ni(Ⅱ) and Cu(Ⅱ) complexes of B and C have been prepared by the reaction of the metal ions and the ligands. Synthesis, characterization, and the properties of the ligands and their metal complexes are reported.

• Bulletin of the Korean Chemical Society
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• v.16 no.3
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• pp.217-221
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• 1995

Axial coordination of anions or water to the square-planar nickel(Ⅱ) complexes of the hexaaza macrocyclic ligands 1, 2, and 3, which contain two extra uncoordinated tertiary nitrogens, have been investigated in aqueous solutions containing HX (X=Cl-, Br-, NO3-, or ClO4-) and/or NaX. The nickel(Ⅱ) complexes exist in the acidic solutions as equilibrium mixtures of the square-planar [Ni(L)]2+ (L=1, 2, and 3) and octahedral species [Ni(H2L)X2]2+ (H2L=diprotonated form of L). Some octahedral complexes have been isolated and characterized. The solution behaviors of the complexes indicate that the formation of the octahedral complexes are significantly promoted by the protonation of the uncoordinated tertiary amines. The proportion of the octahedral complexes depends on the type of acid, and increases in the order of HBr < HNO3 < HCl.

• Bulletin of the Korean Chemical Society
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• v.4 no.5
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• pp.231-234
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• 1983

The stability constant for the complex of $UO_2^{2+}$ with a macrocyclic aminoether ligand, 1,7,10,16-tetraoxa-4,13-diazacyclooctadecane, has determined in aqueous solution. The conductivity and pH metric measurements suggest that the ligand forms a stable 1:1 complex with $UO_2^{2+}$ ion, and the complex is an ionic form, $UO_2L^{2+}$, in aqueous solution. The fact that the ligand does not form a complex with lanthanides, such as $Ce^{3+}$, $Sm^{3+}$, and $Nd^{3+}$ ions, in aqueous solution suggests a possibility of separation of the lanthanide elements from uranium matrix using the macrocyclic aminoether ligand.

• Bulletin of the Korean Chemical Society
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• v.13 no.3
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• pp.256-259
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• 1992

The 14-membered tetraaza macrocyclic ligand 1,8-diethyl-5,12-dimethyl-1,4,8,11-tetraazacyclote tradeca-4,11-diene(B) can be synthesized as its dihydroperchlorate salt by the one-pot reaction of 2-ethylaminoethylamine, methylvinyl ketone, and perchloric acid in absolute ethanol. The reaction of Ni(II) or Cu(II) ion and the salt yields $[M(B)]^{2+}$ (M = Ni(II) or Cu(II)), which reacts with $NaBH_4$ to produce $[M(D)]^{2+}$ (D = 1,8-diethyl-5,12-dimethyl-1,4,8,11-tetraazacyclote tradecane). The complexes $[M(L)]^{2+}$ (L = B or D) have planar geometry and contain two ethyl groups at the donor nitrogen atoms of the ligands. The red solids $[Cu(B)](X)_2(X)$ = $ClO_4-$ or $PF_6^-$) react with water molecules of atmospheric moisture to produce the purple solids in which water molecules are coordinated to the metal ion. Synthesis, characterization, and the properties of the new N-ethylated macrocyclic ligands and their Ni(II) and Cu(II) complexes are reported.

• Bulletin of the Korean Chemical Society
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• v.14 no.2
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• pp.292-294
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• 1993

Three derivatives of poly(ethylenimine) (PEI) are prepared by Ni(II)-template condensation with glyoxal(GO): PEI[Ni(II)-GO]$_{0.08}$ (1), PEI[Ni(II)-GO]$_{0.03}$ (2), and lau$_{0.18}$PEI[Ni(II)-GO]$_{0.03}$ (3). The contents of Ni(II)-macrocyclic center of 1-3 are 8%, 3%, or 3%, respectively, of the monomer residues, and 18% of monomer residues for 3 are laurylated. The pH profiles for k$_{cal}$ and k$_m$ for the deacylation of 4-carboxy-2-nitrophenyl acetate are measured. The relative magnitude of the parameters for 1-3 and different shapes of the pH profiles for 1-3 are explained in terms of the electrostatic and the hydrophobic effects exerted by the metal centers and lauryl groups. For the artificial metalloenzymes built on PEI, therefore, the ionization of functional groups and the affinity toward counter-anions can be controlled by adjusting charge density and the content of hydrophobic groups.