• 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.

• Bulletin of the Korean Chemical Society
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• v.16 no.6
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• pp.518-523
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• 1995

New square planar nickel(Ⅱ) complexes with various 1-alkyl (4a-4c) and 1-hydroxyalkyl (4d-4f) derivatives of the 14-membered pentaaza macrocycle 8-ethyl-8-nitro-1,3,6,10,13-pentaazacyclotetradecane have been synthesized by two-step metal template condensation reactions of ethylenediamine, nitroethane, formaldehyde, and appropriate primary amines. The nitro group and/or hydroxyl group of 4a-4f are not directly involved in the coordination. The nickel(Ⅱ) complexes exist in coordinating solvents such as MeCN, Me2SO, and H2O as equilibrium mixtures of the square planar [Ni(L)]2+(L=4a-4f) and octahedral species [Ni(L)S2]2+(S=solvent molecule). Although the ligand field strength and redox potentials of the complexes are not affected by the nature of the substituents, the formation of octahedral species for 4d-4f in MeCN is strongly restricted by the hydroxyl group. Synthesis, characterization, and solution behaviors of the nickel(Ⅱ) complexes are described.

• Bulletin of the Korean Chemical Society
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• v.19 no.10
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• pp.1099-1105
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• 1998

A series of (diamine)isopropylidenmalonatoplatinum(Ⅱ) complexes and the oxidation products, (diamine)Pt (OOC)2C=C(CH3)2(X)2, (diamine=ethylenediamine(en), 1,2-diaminopropan(dap), N-methylethylenediamine(men); X=OH, OCOCH3, OCOCF3), have been prepared, and their interaction with guanosine-5'-monophosphate (5'-GMP) have been examined by means of 1H NMR spectroscopy. The present platinum(Ⅱ) complexes have shown to interact with 5'-GMP through N7 coordination in two concecutive steps in a similar way as with cisplatin, but no interaction between the present platinum(Ⅳ) complexes and 5'-GMP was observed. However, in the presence of ascorbic acid, the platinum(Ⅳ) complexes have been found to interact with 5'-GMP with the reaction rate depending on their reduction rate.

• Bulletin of the Korean Chemical Society
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• v.15 no.8
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• pp.669-673
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• 1994

Coordination isomers of cis-(N-N)Pt(Glu) prepared by reaction of cis-(N-N)Pt($SO_4$) (N-N=2$NH_3$, ethylenediamine(en),(R,R)-1,2-diaminocyclohexane (DACH), N,N,N',N'-tetramethylethylenediamine (TMEDA)) with barium glutamate in water have been monitored and characterized by $^1H-NMR$, $^{13}C-NMR$, IR, and mass spectra. The reaction at room temperature affords the mixture of O,O'-and N, ${\alpha}$ O-chelated platinum(II) complexes. The O,O'-chelate initially formed isomerized to N,${\alpha}$O-chelate on standing for a long time or increasing temperature. The ratio of the two isomers at room temperature depends on the nature of the nitrogen donor coligand (N-N).

• Bulletin of the Korean Chemical Society
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• v.12 no.2
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• pp.219-224
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• 1991

New binuclear Ni(Ⅱ) and Cu(Ⅱ) complexes with various alkyl derivatives of 1,2-bis(1,3,6,8,10,13-hexaaza-1-cyclotetradecyl) ethane, in which two fully saturated 14-membered hexaaza macrocyclic subunits are linked together by an ethylene chain, have been synthesized by the one step template condensations of formaldehyde with ethylenediamine and appropriate primary alkyl amines in the presence of the metal ions. Each macrocyclic subunit of the double-ring macrocyclic complexes contains one alkyl pendant arm and has a square planar geometry with a 5-6-5-6 chelate ring sequence. The visible spectra and oxidation properties indicate that the metal-metal interaction of the binuclear complexes are not significant. Synthesis, characterization, and the properties of the complexes are presented.

• Bulletin of the Korean Chemical Society
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• v.10 no.4
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• pp.362-366
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• 1989

Square planar nickel(II) and copper(II) complexes of 14-membered macrocyclic ligands containing various alkyl pendant arms at the uncoordinated nitrogen atoms, 1,8-dipropyl, 1,8-dibutyl, 1,8-bis(2-methylpropyl), 1,8-bis(2-ethylhexyl), and 1,8-dibenzyl-1,3,6,8,10,13-hexaazacyclotetradecane have been prepared from the template condensation of ethylenediamine, formaldehyde, and appropriate primary amines in the presence of the metal ion. The spectroscopic and electrochemical properties of these complexes are similar to those of tetraaza macrocyclic complexes and are not affected significantly by the nature of the alkyl groups.

• Bulletin of the Korean Chemical Society
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• v.11 no.4
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• pp.354-357
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• 1990

Synthesis of dichloro cobalt (Ⅲ) complexes of a flexible $N_2O_2-type$ tetradentate ligand, ethylenediamene-N,N'-di-${\alpha}$-isobutyric acid (eddib), has yielded two geometrical isomers, s-cis-$(Co(eddib)Cl_2)- and uns-cis-(Co(eddib)Cl_2)-.$ A series of substitution reactions, $(Co(eddib)Cl_2)^- {\to} (CO(eddib)Cl H_2O) {\to} (Co(eddib)CO_3)^- {\to} (Co(eddib(H_2O)_2)^+$ have been run for each of the two geometrical isomers. The reaction between the s-cis-(Co(eddib)Cl_2)^-$ complex and L-alanine (L-als) or S-methyl-L-cysteine (L-mcy) gave the meridional s-cis-[Co(eddib)(aa)) (aa = L-ala or L-mcy) complex. The S-methyl-L-cysteine was found to coordinate to cobalt (Ⅲ) ion via the nitrogen and oxygen donor atoms.

• Journal of the Korean Applied Science and Technology
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• v.39 no.6
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• pp.924-931
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• 2022

Undenatured castor oil and trimethylolpropane (TMP) were used to obtain bio-based water-based polyurethane. Isophorone diisocyanate (IPDI) was incorporated into the formulation to obtain a transparent film, and ethylenediamine (EDA) was used for chain extension. In order to measure the change in physical properties according to the contents of castor oil and TMP, each tensile strength, elongation, and abrasion resistance test was conducted. As the contents of castor oil and TMP increased, the tensile strength increased, the elongation decreased, and the surface hardened strongly as the respective contents increased.

• Korean Journal of Food Science and Technology
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• v.43 no.6
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• pp.766-772
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• 2011

This study was conducted to evaluate the daily intakes of propyl gallate, EDTA (ethylenediamine tetra acetate), and erythorbic acid for average consumers by age group and the intake of high consumers ($95^{th}$ percentile) in Korea. The average intake of EDTA was $1.14{\mu}g/kg{\cdot}bw/day$, and 0.0% of the ADI (acceptable daily intake) established by JECFA (Joint FAO/WHO Expert Committee on Food Additives). The $95^{th}$ percentile intake of EDTA was $141.24{\mu}g/kg{\cdot}bw/day$ (5.6% of ADI). The average intake of erythorbic acid was $16.93{\mu}g/kg{\cdot}bw/day$, and the 3-6 year-old group had the highest consumption ($58.43{\mu}g/kg{\cdot}bw/day$), which was <1.0% of the ADI established by the EU (European Union). The $95^{th}$ percentile intake of erythorbic acid was $1,320.31{\mu}g/kg{\cdot}bw/day$ and 22.0% of the ADI. In conclusion, daily intakes of propyl gallate, EDTA, and erythorbic acid in Korea were at safe levels in all age groups and also in high consumers.

• Polymer(Korea)
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• v.39 no.1
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• pp.169-173
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• 2015

Metallocene was supported on the silica, which was functionalized with aminosilanes such as aminopropyltrimethoxysilane (1NS) or N-[3-(trimethoxysilyl)propyl]ethylenediamine (2NS), and ionic liquids such as 1-butyl-4-methylpyridinium chloride (Cl), tributylmethylammonium chloride (Amm), benzyldimethyltetradecylammonium chloride (Ben), 1-butyl-1-methylpyrrolidinium chloride (Pyr), and then ethylene polymerizations were performed. The Zr contents of $SiO_2/1NS/IL/(n-BuCp)_2ZrCl_2$ and $SiO_2/2NS/IL/(n-BuCp)_2ZrCl_2$ were lower than those of only aminosilane-treated silicas. However, the polymerization activity of $SiO_2/1NS/IL/(n-BuCp)_2ZrCl_2$ was higher than that of $SiO_2/1NS/(n-BuCp)_2ZrCl_2$. The polymerization activity of $SiO_2/2NS/IL/(n-BuCp)_2ZrCl_2$ was lower than that of $SiO_2/2NS/(n-BuCp)_2ZrCl_2$ due to much lower Zr content.