• Title/Summary/Keyword: dinuclear

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Synthesis, Characterization and Property Studies on a Dinuclear Copper(II) Complex with Dipyridine Derivate and Acetylacetone

  • Zhao, Pu Su;Guo, Zhi Yan;Sui, Jing;Wang, Jing;Jian, Fang Fang
    • Bulletin of the Korean Chemical Society
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    • v.32 no.1
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    • pp.49-52
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    • 2011
  • A dinuclear copper(II) complex of [$Cu_2(aceace)_4$(dipyph)] [aceace = acetylacetone, dipyph = 1,4-di(4-pyridylethene-2-yl-)benzene] has been synthesized and characterized by elemental analysis, IR and X-ray single crystal diffraction. It crystallizes in the monoclinic system, space group P21/c, with lattice parameters a = 7.9584(16) $\AA$, b = 18.594(4) $\AA$, c = 15.063(4) $\AA$ $\beta=120.97(2)^o$ and $M_r$ = 807.85 ($C_{40}H_{44}Cu_2N_2O_8$), Z = 2. Each of the $Cu^{2+}$ ion adopts a square pyramid geometry and coordinates with four oxygen atoms from two aceace ligands and one nitrogen atom from dipyph bidentate ligand. Magnetic measurement shows that the Weiss constant and Curie constant for the title compound are -0.22 K and 0.1154 emu K/mol, respectively. Thermal stability data indicate that the title complex undergoes two steps decomposition and the residue is $Cu_2O_4$. In the potential range of -1.5 ~ 0.8 V, the title complex represents an irreversible electrochemical process.

The Roles of Metal Ions and Water Molecules in the Hydrolysis of Bis(p-nitrophenyl)phosphate as a DNA Model Catalyzed by Dinuclear Ni(II) Complex (DNA 모델인 Bis(p-nitrophenyl)phosphate에 대한 2핵 Ni(II) 착 화합물의 촉매 가수분해 반응에서 물 분자와 금속 이온의 역할)

  • Sung, Nack-Do;Yun, Ki-Seob
    • Applied Biological Chemistry
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    • v.48 no.2
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    • pp.115-119
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    • 2005
  • The catalytic hydrolysis reactivities of dinuclear nickel (II) complex, ${\mu}-aquapentaaqua[{\mu}-3,6-bis(6'-methyl-2'-pyridyl)pyridazine]chlorodinickel\;(II)$ trichloride trihydrate (APNT) for bis(p-nitrophenyl) phosphate (BNPP) as a DNA model compound were investigated. The dissociation constants of APNT were $pKa_1=7.9$ and $pKa_2=9.6$, respectively. The hydrolysis rate constant of BNPP compound by APNT was showed the rate enhancement of about 370,000 times in the case of none catalyst at pH 7.0 and $50^{\circ}C$. Based on the findings, we proposed the catalytic cycle for the hydrolysis of BNPP by APNT complex. The metal ions of dinuclear nickel (II) complex significantly enhance the transfer rate of phosphoryl group in the catalytic process and the water molecules as nucleophile and proton transfer agent act in different steps.

A Study on the Complexation of Nickel(II) Ion with 2-(2-Hydroxyethylamino)-2-(hydroxymethyl)-1,3-propanediol(Monotris) in Aqueous Solution (수용액 중에서 Ni(II) 이온과 2-(2-Hydroxyethylamino)-2-(hydroxymethyl)-1,3-propanediol(Monotris)과의 착물형성에 대한 연구)

  • Hong, Kyung-Hee;Shim, Seung-Bo;Oh, Seong-Geun;Chun, Yong-Jin
    • Journal of the Korea Academia-Industrial cooperation Society
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    • v.11 no.12
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    • pp.5221-5231
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    • 2010
  • The complex formation from Ni(II) ion and 2-(2-Hydroxyethylamino)-2-(hydroxymethyl)-1,3-propanediol(Monotris) in aqueous solution at $25^{\circ}C$ and at ionic strength of 0.10M has been studied potentiometrically. In the Monotris(L) comlex $NiL^{2+}$, hydroxyl oxygen atom as well as the amine nitrogen of the ligand are coordinated to the Ni(II) ion.. The complex $NiL^{2+}$ undergoes further dissociation as the pH is increased forming triply deprotonated dinuclear complex $Ni_2L_2H_{-3}^+$.

Synthesis and Crystal Structures of Copper(II) Complexes with Schiff Base Ligands: [Cu2(acpy-mdtc)2(HBA)(ClO4)]·H2O and [Cu2(acpy-phtsc)2(HBA)]·ClO4

  • Koo, Bon Kweon
    • Bulletin of the Korean Chemical Society
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    • v.34 no.11
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    • pp.3233-3238
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    • 2013
  • Two new Cu(II) complexes, $[Cu_2(acpy-mdtc)_2(HBA)(ClO_4)]{\cdot}H_2O$ (1) (acpy-mdtc- = 2-acetylpyridine S-methyldithiocarbamate and $HBA^-$ = benzilic acid anion) and $[Cu_2(acpy-phtsc)_2(HBA)]{\cdot}ClO_4$ (2) (acpy-$phtsc^-$ = 2-acetylpyridine 4-phenyl-3-thiosemicarbazate) have been synthesized and characterized by elemental analysis, infrared spectroscopy, thermogravimetric analysis, and single crystal X-ray diffraction. The X-ray analysis reveals that the structures of 1 and 2 are dinuclear copper(II) complexes bridged by two thiolate sulfur atoms of Schiff base ligand and bidentate bridging $HBA^-$ anion. For 1, each of the two copper atoms has different coordination environments. Cu1 adopts a five-coordinate square-pyramidal with a $N_2OS_2$ donor, while Cu2 exhibits a distorted octahedral geometry in a $N_2O_2S_2$ manner. For 2, two Cu(II) ions all have a five-coordinate square-pyramidal with a $N_2OS_2$ donor. In each complex, the Schiff base ligand is coordinated to copper ions as a tridentate thiol mode.

Copper(II) Coordination Polymers Assembled from 2-[(Pyridin-3-ylmethyl)amino]ethanol: Structure and Magnetism

  • Han, Jeong-Hyeong;Shin, Jong-Won;Min, Kil-Sik
    • Bulletin of the Korean Chemical Society
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    • v.30 no.5
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    • pp.1113-1117
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    • 2009
  • The one-dimensional coordination polymers, $[Cu^{II}(L)(NO_3)_2]_n$ (1) and {$[Cu^{II}(L)(NO_3)]{\cdot}2H_2O}_{2n} (2), were synthesized from $Cu(NO_3)_2{\cdot}3H_2O$ and 2-[(pyridin-3-ylmethyl)amino]ethanol (L, PMAE) in methanol by controlling the molar ratio of copper(II) salt. Copper(II) ion in 1 has one pyridine group of PMAE whose an aminoethanol group coordinates adjacent copper(II) ion. As the pyridine group is bonded to neighboring copper(II) ion, 1 becomes a one-dimensional chain. Contrary to 1, the structure of 2 shows that the oxygen atom of ethoxide group is bridged between two copper(II) ions, which forms a dinuclear complex. Additionally, the pyridine group of PMAE included one dinuclear unit is coordinated to the other dimeric one each other, which leads to a one-dimensional polymer. Due to the structural differences, 1 exhibits weak antiferromagnetic interaction, while 2 shows strong antiferromagnetic interaction. Due to direct spin exchange via oxygen of PMAE 2 has a much strong spin coupling than 1.