• Bulletin of the Korean Chemical Society
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• 제27권11호
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• pp.1747-1751
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• 2006

The dinuclear tetraazadiphenol macrocyclic nickel(II) complexes [$Ni_2$([20]-DCHDC)]$Cl_2$ (I), [$Ni_2$([20]-DCHDC)]$(ClO_4)_2{\cdot}2CH_3CN $ (II(b)) and [$Ni_2$([20]-DCHDC)$(NCS)_2$] (III) {$H_2$[20]-DCHDC = 14,29-dimethyl-3,10,18,25-tetraazapentacyclo-[25,3,1,$0^{4,9}$,$1^{12,16}$,$0^{19,24}$]ditriacontane-2,10,12,14,16(32),17,27(31), 28,30-decane-31,32-diol} have been synthesized by self-assembly and characterized by elemental analyses, conductances, FT-IR and FAB-MS spectra, and single crystal X-ray diffraction. The crystal structure of II(b) is determined. It crystallizes in the monoclinic space group P2(1)/c. The coordination geometries around Ni(II) ions in I and II(b) are identical and square planes. In complex III each Ni(II) ion is coordinated to $N_2O_2$ plane from the macrocycle and N atoms of NCS- ions occupying the axial positions, forming a square pyramidal geometry. The nonbonded Ni…Ni intermetallic separation in the complex II(b) is 2.8078(10) $\AA$. The FAB mass spectra of I, II and III display major fragments at m/z 635.1, 699.4 and 662.4 corresponding to [$Ni_2$([20]-DCHDC)(Cl + 2H)]$^+$, [$Ni_2$([20]-DCHDC)$(ClO_4\;+\;2H)]^+$ and [$Ni_2$([20]-DCHDC)(NCS) + 6H]$^+$, respectively.

• 대한화학회지
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• 제27권2호
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• pp.83-94
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• 1983

EHT calculation의 고유함수를 사용하여 $[M(II)O_3N_3]$ 및 $[Ni(II) O_2N_4]$ 형태착물[M(II) = Co(III), Ni(II) 및 Cu(II)]의 쌍극자 모멘트에 대한 cis 및 trans 구조의 영향을 고찰하였다. cis$[M(Ⅱ)O_3N_3]$ 형태착물의 계산한 쌍극자 모멘트가 trans착물의 계산한 쌍극자 모멘트 값보다 큰 값을 가지며 trans 착물의 쌍극자 모멘트 값이 실험치 범위안에 들었다. 그러나 $[Ni(II) O_2N_4]$ 착물의 경우 cis 착물의 쌍극자 모멘트 값이 실험치 범위안에 들었다. 이 결과는 $[Co(III)O_3N_3]$ 형태착물이 trans 구조, $[Ni(II) O_2N_4]$ 형태착물은 cis 구조를 가졌음을 암시하며 이는 실험결과와 일치한다. $[M(II)O_3N_3]$ 형태착물에서 세개의 두자리 (O-N)리간드가 금속이온에 배위되어 있으며 $[Ni(II) O_2N_4]$형태 착물에서는 두개의 세자리(O-N-N) 리간드가 Ni(II) 이온에 배위되어 있음).

• 대한화학회지
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• 제32권3호
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• pp.227-232
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• 1988

$Hg^{2+}$촉매 존재하에서 cis-amminechlorobis(ethylenediamine)cobalt(III)의 Cl이 $H_2O$로 치환되는 반응을 전자흡수 스펙트라로 속도론적 연구를 하였다. 그 결과 $cis-[Co(en)_2(NH_3)Cl]^{2+}$에 대해서 각각 1차인 총괄반응이 2차반응이다. 활성화 파라메타인 ${\Delta}H^{\neq}$와 ${\Delta}S^{\neq}$는 각각 12.9 kcal/mol, -19.3 e.u 이고 $Hg^{2+}$에 의한 반응속도상수는 $1.65{\times}10^{-2}l/mol.sec$가 됨을 알았다. 이러한 속도 자료로부터 본 반응계의 Cl이 $H_2O$로 치환되는 반응은 촉매인 $Hg^{2+}$가 관여하는 Id 메카니즘을 제안하였다.

• Bulletin of the Korean Chemical Society
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• 제27권9호
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• pp.1381-1385
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• 2006

Cobalt (cyclam) complex has been successfully immobilized onto SBA-15, and proven to be an active catalyst for the epoxidation of styrene with tert-butyl hydroperoxide as a terminal oxidant. The selectivity for styrene oxide was observed to be up to 66% with 40% styrene conversion after 12h reaction time. The reversible redox cycle between Co(III) and Co(II) couple which was supposed to play key role during the epoxidation reaction was supported by a cyclic voltametry analysis. The textural properties of the catalyst was characterized by XRD, N2 adsorption-desorption, and TEM analysis.

• 공업화학
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• 제26권2호
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• pp.132-137
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• 2015

BEA형 제올라이트를 알칼리용액으로 처리하여 결정구조 내에 메조세공이 형성되도록 제조하고, 세공 내에 균일계 키랄 Co(III) 살렌을 고정화시켰다. 메조세공 BEA-제올라이트에 고정화된 이핵형 Co-$GaCl_3$ 살렌 촉매는 말단 에폭사이드의 산소고리를 카르복실산으로 여는 키랄 반응에 대하여 높은 활성을 나타내었다. 이 반응을 통하여 라세믹 에폭사이드로부터 다양한 모노 에스테르 유도체를 중간 정도의 광학선택도(47~69 ee%)로 합성할 수 있었다. 키랄(S)-ECH를 반응물로 사용하면, 이들은 키랄 살렌 촉매 존재하에서 카르복시 산에 의하여 에폭사이드의 링이 광학선택적으로 열리며, 생성된 화합물을 염기용액에서 탈염산 처리하면 다시 에폭사이드 링이 형성되면서 광학순도가 매우 높은 모노에스터 에폭사이드 (R)-GB (98 ee% 이상)가 얻어졌다. 고정화촉매는 매우 용이하게 제조될 수 있었으며, 특별한 재생처리 없이 여러번 재사용하여도 촉매의 활성이 유지되었다.

• Bulletin of the Korean Chemical Society
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• 제14권4호
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• pp.439-444
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• 1993

The aerobic oxidation of the Fe(II) complex of 1,4,8,11-tetraazacyclotetradecane, [Fe(cyclam)$(CH_3CN)_2](ClO_4)_2$, in MeCN in the presence of a few drops of $HClO_4$ leads to low spin Fe(III) species [Fe(cyclam)$(CH_3CN)_2](ClO_4)_3$. The Fe(III) cyclam complex is further oxidized in the air in the presence of a trace of water to produce the deep green binuclear bismacrocyclic Fe(II) complex $[Fe_2(C_{20}H_{36}N_8)(CH_3CN)_4](ClO_4)_4{\cdot}2CH_3CN$. The Fe(II) ions of the complex are six-coordinated and the bismacrocyclic ligand is extensively unsaturated. $[Fe_2(C_{20}H_{36}N_8)(CH_3CN)_4](ClO_4)_4{\cdot}2CH_3CN$ crystallizes in the monoclinic space group $P2_1/n$ with a= 13.099 (1) ${\AA}$, b= 10.930 (1) ${\AA}$, c= 17.859 (1) ${\AA}$, ${\beta}$= 95.315 $(7)^{\circ}$, and Z= 2. The structure was solved by heavy atom methods and refined anisotropically to R values of R= 0.0633 and $R_w$= 0.0702 for 1819 observed reflections with F > $4{\sigma}$ (F) measured with Mo K${\alpha}$ radiation on a CAD-4 diffractometer. The two macrocyclic units are coupled through the bridgehead carbons of ${\beta}$-diimitie moieties by a double bond. The double bonds in each macrocycle unit are localized. The average bond distances of $Fe(II)-N_{imine}$, $Fe(II)-N_{amine}$, and $Fe(II)-N_{MeCN}$ are 1.890 (5), 2.001 (5), and 1.925 (6) ${\AA}$, respectively. The complex is diamagnetic, containing two low spin Fe(II) ions in the molecule. The complex shows extremely intense charge transfer band in the near infrared at 868 nm with ${\varepsilon}$= 25,000 $M^{-1}cm^{-1}$. The complex shows a one-electron oxidation wave at +0.83 volts and two one-electron reduction waves at -0.43 and-0.72 volts vs. Ag/AgCl reference electrode. The complex reacts with carbon monoxide in $MeNO_2$ to form carbonyl adducts, whose $v_{CO}$ value (2010 $cm^{-1}$) indicates the ${\pi}$-accepting property of the present bismacrocyclic ligand.

• Bulletin of the Korean Chemical Society
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• 제26권9호
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• pp.1381-1384
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• 2005

Surface modification of tridimensional cubic mesoporous silica, SBA-16, was investigated with pendant arm functionalized cobalt diaminosarcophagine (diAMsar) cage complex which covalently grafted onto the silica surface through the silication with sylanol group. The spectroscopic results showed that the mesoporous structure was preserved under the $[Co(diAMsar)]^{3+}$ grafting reaction condition. Successful grafting prevented the cobalt diAMsar cage from leaching out from the SBA-16 support.

• Bulletin of the Korean Chemical Society
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• 제30권2호
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• pp.389-396
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• 2009

MFI structural zeolite (ZSM-5 or Sililcalite) was treated with HF solution to introduce mesoporous channels in the microporous crystals. Inner mesopore size could be controlled from 2.5 to 3.5 nm by changing the concentration of HF solution. The pore structure of HF-treated MFI zeolite was studied by instrumental analysis. The active Co (III) salen complex monomers were successfully anchored non-covalently on the surfaces of mesoporous MFI-type zeolite. These heterogeneous catalysts could be applied in asymmetric ring opening of terminal epoxides by phenol derivatives. It showed very high enantioselectivity and yield up to 95% in the catalytic synthesis of optically active $\alpha$-aryloxy alcohol compounds.

• Bulletin of the Korean Chemical Society
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• 제26권6호
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• pp.943-946
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• 2005

An effective spectrophotometric determination of palladium with 4-(2-pyridylazo)-resorcinol (PAR) using molten naphthalene as a diluent has been studied. A red complex of palladium with PAR is formed at 90 ${^{\circ}C}$. In the range of pH 9.0-11.0, the complex is quantitatively extracted into molten naphthalene. The organic phase is anhydrously dissolved in $CHCl_3$ to be determined spectrophotometrically at 520 nm against the reagent blank. Beer’s law is obeyed over the concentration range of 0.1-2 ${\mu}g{\cdot}mL^{-1}$. The molar absorptivity and Sandell’s sensitivity are 8.0 ${\times}\;10^5\;L{\cdot}mol^{-1}{\cdot}cm^{-}1\;and\;0.49\;{\mu}g{\cdot}cm^{-2}$ respectively. From the results of tolerance limits, it was found that there was no interferences were observed for most of the ions examined and those somewhat high interferences by Co(II), Fe(II) and Bi(III) could be effectively masked by EDTA.

• BMB Reports
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• 제40권4호
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• pp.562-570
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• 2007

Soluble or cell-bound IL-1 receptor accessory protein (IL-1RAcP) does not bind IL-1 but rather forms a complex with IL-1 and IL-1 receptor type I (IL-1RI) resulting in signal transduction. Synthetic peptides to various regions in the Ig-like domains of IL-1RAcP were used to produce antibodies and these antibodies were affinity-purified using the respective antigens. An anti-peptide-4 antibody which targets domain III inhibited 70% of IL-$1\beta$-induced productions of IL-6 and PGE2 from 3T3-L1 cells. Anti-peptide-2 or 3 also inhibited IL-1-induced IL-6 production by 30%. However, antipeptide-1 which is directed against domain I had no effect. The antibody was more effective against IL-$1\beta$ compared to IL-$1\alpha$. IL-1-induced IL-6 production was augmented by coincubation with PGE2. The COX inhibitor ibuprofen blocked IL-1-induced IL-6 and PGE2 production. These results confirm that IL-1RAcP is essential for IL-1 signaling and that increased production of IL-6 by IL-1 needs the co-induction of PGE2. However, the effect of PGE2 is independent of expressions of IL-1RI and IL-1RAcP. Our data suggest that domain III of IL-1RAcP may be involved in the formation or stabilization of the IL-1RI/IL-1 complex by binding to epitopes on domain III of the IL-1RI created following IL-1 binding to the IL-1RI.