• 대한화학회지
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• 제24권2호
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• pp.121-128
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• 1980

Ambidentate 리간드인 isonitrosobenzoylacetone을 리간드로 하는 금속착물, tris(isonitrosobenzoylacetonato)cobalt(III) 및 bis(isonitrosobenzoylacetonato)palladium(II)을 합성한 후 분광학적 방법에 의하여 이들의 결합구조를 조사하였다. 즉 착물에서 리간드는 아세틸기의 산소 및 이소니트로소의 질소원자를 통하여 금속에 배위되어 5원의 킬레이트고리를 이루고 있음을 알 수 있었다. 이 결합구조는 Patel과 Haldar등이 얻었던 isonitrosoacetylacetone착물의 그 것들과 유사하다.

• Bulletin of the Korean Chemical Society
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• 제18권8호
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• pp.850-856
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• 1997

A series of tetradentate Schiff-base ligands; 1,3-bis(salicylideneimino) propane, 1,4-bis(salicylideneimino)butane, and 1,5-bis(salicylideneimino)pentane, and their Cu(Ⅱ) and Ni(Ⅱ) complexes have been synthesized. The properties of ligands and complexes have been characterized by elemental analysis, IR, NMR, UV-Vis spectra, molar conductance, and thermogravimetric anaylsis. The mole ratio of Schiff base to metal at complexes was found to be 1 : 1. All complexes were four-coordinated configuration and non-ionic compound. The electrochemical redox processes of the ligands and their complexes in DMF solution containing 0.1 M TEAP as supporting electrolyte have been investigated by cyclic voltammetry, chronoamperometry, differential pulse voltammetry at glassy carbon electrode, and by controlled potential coulometry at platinum gauze electrode. The redox process of the ligands was highly irreversible, whereas redox process of Cu(Ⅱ) and Ni(Ⅱ) complexes was observed as one electron transfer process of quasi-reversible and diffusion-controlled reaction. Also the electrochemical redox potentials of complexes were affected by chelate ring size of ligands. The diffusion coefficients of Cu(Ⅱ) and Ni(Ⅱ) complexes in DMF solution were determined to be 4.2-6.6×10-6 cm2/sec. Also the exchange rate constants were determined to be 3.6-9.7×10-2 cm/sec.

• Macromolecular Research
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• 제13권1호
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• pp.2-7
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• 2005

A series of ethylene polymerization catalysts based on tridentate bis-imine ligands coordinated to iron and cobalt was reported. The ligands were prepared through the condensation of sterically bulky anilines with allyloxy-and benzyloxy-substituted 2,6-acetylpyridines. The pre-catalyst complexes were penta-coordinate species of the general formula $\{[(ArN=C(Me))_2(4-RO-C_5H_3N)]MCl_2\}$ (Ar=ortho dialkyl-substituted aryl ring; R=allyl, benzyl; M=Fe, Co). In the presence of ethylene and methyl alumoxane cocatalysts, these complexes were active for the polymerization of ethylene, with activities lower than those of metal complexes of the general formula $\{[(2-ArN=C(Me)_2C_5H_3N]MCl_2\}$ (Ar=ortho dialkyl-substituted aryl ring; M=Co, Fe), containing no substituents in 2,6-acetylpyridine ring. The effects of the catalyst structure and temperature on the polymerization activity, thermal properties, and molecular weight were discussed.

• Bulletin of the Korean Chemical Society
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• 제20권3호
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• pp.355-361
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• 1999

To improve the volatility and stability of lead complexes, the principle of stabilization by saturating the metal coordination sphere by intramolecular coordination through a β-diketonates with an ethereal group has was tested. Several new lead complexes with alkoxyalkyl-substituted β-diketonates, Pb(R1C(O)CHC(O)(CH2)3OR2)2(Rl=t-Bu, Me, OMe, i-Pr, R2=Me, Et), or carboxylate, Pb(OC(O)(CH2)3OEt)2, were prepared by the reaction between Pb(OAc)2 and corresponding alkoxyalkyl-substituted β-diketonates, and they were found to have a viscous liquid phase. The nature of the head (β-diketonate or carboxylate) or tails and substituents of β-diketonates appeared not to be important for the formation of the liquid phase. It is worth mentioning that Pb(OAc)2, which has limited use due to its low solubility, was successfully adopted as a starting material for the preparation of new lead complexes. Easy hydrolysis, reaction with HCl, and 13C NMR spectra indicated that tail portions were not coordinated to the metal as a copper derivative, Cu(t-BuC(O)CHC(O)(CH2)3OMe)2. All these complexes were not volatile enough for the MOCVD experiments, but a methyl derivative, Pb(MeC(O)CHC(O)(CH2)3OEt)2, showed some sublimation. The methoxy derivative, Pb(MeOC(O)CHC(O)(CH2)3OEt)2, was thermally unstable due to possible equilibrium between species coordinating with a keto oxygen atom and an ethereal atom of a methoxy group, which was confirmed by IR and 13C NMR spectra.

• Bulletin of the Korean Chemical Society
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• 제31권2호
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• pp.453-456
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• 2010

The structural and energetic preferences of thiacalix[4]biscrown-5 with and without alkali metal ions ($Na^+$, $K^+$, $Rb^+$, and $Cs^+$) have been theoretically investigated for the first time using molecular dynamic (MD) simulations and density functional theory (MPWB1K/6-31G(d)//B3LYP/6-31G(d)) methods. The formation of the metal ion complex by the host is mainly driven by the electrostatic attraction between crown-5 oxygens and a cation together with the minor contribution of the cation-$\pi$ interaction between two facing phenyl rings around the cation. The computed binding energies and the atomic charge distribution analysis for the metal binding complexes indicate the selectivity toward a potassium ion. The theoretical results herein explain the experimentally observed extractability order by this host towards various alkali metal ions. The physical nature and the driving forces for cation recognition by this host are discussed in detail.

• 분석과학
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• 제8권4호
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• pp.449-456
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• 1995

Novel macrocyclic ligands modified with pendant arms, N, N', N'', N''', N'''', N'''''-hexakis(2-aminoethyl)-1, 4, 7, 10, 13, 16-hexaazacyclootadecane [$L_3$, Fig.1] and 1, 4, 7-tris(3-(o-hydroxyphenyl)propyl)-1, 4, 7-triazacyclononane [$L_4$, Fig.1] have been synthesized, and the protonation of $L_3$ and $L_4$ and stability constants of $L_3$ with bivalent transition metal ions and rare earth metal ions were determined by a potentiometry. The obtained results show that the complex formation of $L_3$ depends on the metal ligand ratios, and the stability of the metal complexes does not depend on the sizes of the metal ions, but on the nature of the metal ions. The structures of the rare earth complexes for $L_4$ were characterized by an X-ray absorption spectrometry(XAFS).

• 한국대기환경학회지
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• 제34권2호
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• pp.269-280
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• 2018

This paper reports the results of field evaluation to determine the levels of heavy metals in major industrial complexes in Korea over a seven year period (2007~2013). The measurement of heavy metal was conducted using quartz fiber filter sampling and ICP-AES analysis. In order to validate the analytical performance of these methods, studies were also carried out to investigate data quality control(QC) parameters, such as the method detection limit (MDL), repeatability, and recovery efficiencies. The average concentrations of total suspended particulates (TSP) for the nine industrial complexes in Korea were $104{\sim}169{\mu}g/m^3$, which was higher than other industrial complexes and urban areas. The Sihwa and Banwol industrial complexes were shown to be the biggest contributing sources to high TSP emission ($159{\mu}g/m^3$ and $169{\mu}g/m^3$, respectively). The concentrations of heavy metals in TSP were higher in the order of Fe>Cu>Zn, Pb, Mn>Cr, Ni, As and Cd. It was observed that Fe was the highest in the Gwangyang and Pohang steel industrial complexes. The concentrations of Zn and Pb were high in Onsan, Sihwa and Banwol industrial complexes, and this was attributed to the emission from the nonferrous industry. Additionally, Cr and Ni concentrations were high in the Sihwa and Banwol industrial complexes due to plating industry. On the other hand, Ulsan and Onsan industrial complexes showed high Cr and Ni concentrations as a response to the emission of metal industry related to automobile. The correlation analysis revealed the high correlation between Cr and Ni in plating industry from Sihwa and Banwol industrial complexes. Adding to this, components related to coal combustion and road dust showed high correlation in Pohang and Gwangyang industrial complexes. Then Onsan and Ulsan industrial complexes showed high correlation among components related to the nonferrous metals.

• 대한화학회지
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• 제32권5호
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• pp.428-435
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• 1988

Isonitrosoacetylacetone 및 여러가지 디아민으로 부터 유도된 리간드와의 니켈(Ⅱ) 및 팔라듐(Ⅱ) 착물들, 즉, $Ni(IAA)_2-en$, $Ni(IAA)_2-pn$, $Ni(IAA)_2-tn$, Pd(IAA)$_2$-en, PdCl(IAA)-pn, 그리고 Pd(IAA)$_2$-tn을 합성하였다. 여기서 (IAA)$_2$-en, (IAA)$_2$-pn, (IAA)$_2$-tn, 그리고 (IAA)-pn 은 각각 N,N'-enthylenbis(isonitrosoacetylacetone imine), N,N'-propylenebis(isonitrosoacetylacetone imine), N,N'-trimethylenebis(isonitrosoacetylacetone imine), 그리고 N-(2-aminopropyl)isonitrosoacetylacetone imine 을 표시한다. 합성된 이들 니켈(Ⅱ) 및 팔라듐(Ⅱ) 착물들의 원소분석, 적외선 스펙트럼, 핵자기공명스펙트럼, 그리고 전자스펙트럼등을 측정한 결과, $Ni(IAA)_2$-tn 및 Pd(IAA)$_2$-en에서 리간드의 한 isonitroso 기는 질소원자를 통하여 금속이온에 배위되어 5각형 고리를 이루고, 다른 isonitroso기는 산소원자를 통하여 금속이온에 배위되어 6각형 고리를 이룬다. 그리고, $Ni(IAA)_2$-en, Ni(IAA)$_2$-pn, 그리고 Pd(IAA)$_2$-tn에서 리간드의 두개의 isonitroso기는 모두 질소원자를 통하여 금속이온에 배위되어 5각형 고리를 이룬다. 한편, PdCl(IAA)-pn 은 팔라듐과 한분자의 isonitrosoacetylacetone 및 propylenediamine의 반응으로 생성된다.

• 한국고분자학회:학술대회논문집
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• 한국고분자학회 2006년도 IUPAC International Symposium on Advanced Polymers for Emerging Technologies
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• pp.155-155
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• 2006

The most commercially and academically advanced catalysts of late transition metals are diimine complexes based on Pd(II)/Ni(II) and bis(imino)pyridyl complexes based on Fe(II)/Co(II). It is well known that the former systems yield branched polyethylenes and the latter linear PEs. In this presentation, effect of extremely bulky ligands with electron withdrawing/donating substituents at a remote position from Ni(II) metal center and of using multi-nuclear homo or hetero multi-metal on the ethylene polymerization is to be paged.

• Bulletin of the Korean Chemical Society
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• 제33권7호
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• pp.2299-2304
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• 2012

Two new metal(II) complexes, $[Mn(dpa)(phen)(H_2O)_2]_n$ (1) ($H_2dpa$ = dephenic acid, phen = 1,10-phenanthroline) and $[Ni_2(nda)(phen)_2(H_2O)_6](nda)(H_2O)$ (2) ($H_2nda$ = 2,6-naphthalenedicarboxylic acid) have been synthesized and characterized by elemental analysis, infrared spectroscopy, thermogravimetric analysis, and single crystal X-ray diffraction. In complex 1, Mn(II) ion is six-coordinated, and Mn(II) ions are bridged by dpa ligands into 1D chains. While, the complex 2 is dimer and two Ni(II) ions are bridged by one nda ligand cooperated with the terminal ligand phen. In each complex, the dicarboxylate ligand is coordinated to metal(II) ions as a bis-monodentate.