• Journal of the Korean Chemical Society
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• v.50 no.1
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• pp.89-93
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• 2006

• Journal of the Korean Chemical Society
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• v.51 no.1
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• pp.101-105
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• 2007

• Journal of the Korean Chemical Society
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• v.47 no.6
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• pp.667-670
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• 2003

• Journal of the Korean Chemical Society
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• v.30 no.4
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• pp.345-351
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• 1986

Monoxo-bridged binuclear molybdenum(V) complex, $[Mo_2O_3\;(bipy)_2\;(NCS)_4]$ in aqueous acetone mixture produces the corresponding dioxo-bridged binuclear molybdenum(V) complex, $MoO_4(bipy)_2(NCS)_2$. The rate of conversion of $[Mo_2O_3(bipy)_2(NCS)_4]$ to $MoO_4(bipy)_2(NCS)_2$ has been measured by spectrophotometric method. The rate of formation of dioxo-bridged binuclear molybdenum(V) complexes with solvent water follows the rate law, rate = k$[Mo_2O_3(bipy)_2(NCS)_4]\;[H_2O]$. The reaction mechanism for the formation of dioxo-bridged complex is discussed. The observed negative volume of activation shows that the complex is strongly attracted to the solvent molecules at transition state.

• Korean Journal of Crystallography
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• v.17 no.2
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• pp.46-50
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• 2006

The dinuclear copper(II) complex {[Cu(pmea)Cl][Cu$(H_2O)_3]}Cl_2{\cdot} H_2O$ (1) (Hpmea=bis(2-pyridvlmethyl)amino-2-ethanoic acid) has been synthesized and characterized. It crystallizes in the monoclinic system $P2_1/c$, a=9.0008(6) ${\AA}$, b=28.0171(19) ${\AA}$, c=8.5590(6) ${\AA}$, $\beta$=104.2280(10)$^{\circ}$, V=2092.2(2) ${\AA}^3$, Z=4. Crystal structure of 1 reveals a syn-anti carboxylate-bridged dinuclear complex, in which the coordination environment around each copper atom exhibits a distorted square-pyramid and a distorted square plane, respectively.

• Journal of the Korean Chemical Society
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• v.32 no.3
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• pp.203-210
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• 1988

Mono-oxo-bridged binuclear molybdenum(V) complex, $[Mo_2O_3(Phen)_2(NCS)_4]$ produces di-oxo-bridged binuclear molybdenum(V) complex, $[Mo_2O_4(Phen)_2(NCS)_2]$ in water + co-solvent, where the co-solvent are acetone, acetonitrile and N,N-dimethylformamide. The rate of conversion of $[Mo_2O_3(Phen)_2(NCS)_4]\;into\;[Mo_2O_4(Phen)_2(NCS)_2]$ has been measured by spectrophotometric method. Temperature was $10^{\circ}C$ to $40^{\circ}C$ and pressure was varied up to 1500 bar. The rate constants are increased with increasing water mole fraction and decreased with increasing concentration of hydrogen ion. The order of oxygen ring formation reaction rate in various cosolvent is as follows, ACT > AN > DMF which is agreed with solvent dielectric constants. The observed negative activation entropy ($[\Delta}S^{\neq}$), activation volume($[\Delta}V^{\neq}$) and activation compressibility coefficient(${\Delta}{\beta}^{\neq}$) values show that the solvent water molecule is strongly attracted to the complex at transition state. From these results, the oxygen ring formation reaction of $[Mo_2O_3(Phen)_2(NCS)_4]$ is believed association mechanism.

• Journal of the Korean Chemical Society
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• v.38 no.7
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• pp.485-495
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• 1994

Several new symmetric and asymmetric homo and hetero dinuclear complexes of the type $[Cl(dppp)(NO)_2M({\mu}-pyz)M'(NO)_2(dppp)Cl][ClO_4]_2$ and $[Cl(phen)(NO)_2M({\mu}-pyz)M'(NO)_2(dppp)Cl][ClO_4]_2$(M,M'= Mo or W; phen = 1,10-phenanthroline; dppp = 1,3-bis(diphenylphosphino)propane; pyz = 1,4-pyrazine) were synthesized in three-steps starting from $[M(NO)_2Cl_2]_n(M = Mo, W)$. The final products were purified by eluting it through silica gel column ($2{\times}20$ cm) with acetone as the eluent. Characterization of these complexes and some related complexes was accomplished through UV-vis., $^1H$-NMR, $^{13}C$-NMR and IR spectroscopies as well as elemental analysis. The infrared spectra indicate that the NO groups occupy cis-positions of the octahedral. The $^1H$ and $^{13}C-NMR$ data for the new compounds revealed a dimeric structures with bridged pyz.

• Journal of the Korean Chemical Society
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• v.38 no.11
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• pp.808-818
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• 1994

The neutral compounds [$MCl_3L_2$(MeCN)] (M = Mo, V: L = $PPh_3$, 1/2 phda) have been prepared from the reaction of starting material $MCl_z$ (M = Mo; z = 5, M = V; z = 3) with N,P-donating ligands in acetonitrile solution. Addition of $AgClO_4$ to these neutral monomeric compounds in acetone solution were produced [$MCl_3-_nL_2(MeCN)(S)_n$]$(ClO_4)_n$ (n = 1, 2 : s = solvent). Finally treatment of bivalent cationic compound and neutral compound was formed chloride bridged dinuclear complex $[(MeCN)(L)_2ClM({\mu}-Cl)_2M'Cl(L)_2(MeCN)](ClO_4)_2$ and treatment of univalent cationic compound with half equivalent pyrazine to pyrazine bridged complex $[(MeCN)(L)_2Cl_2M({\mu}-pyz)M'Cl_2(L)_2(MeCN)](ClO_4)_2$. These complexes are characterized by elemental analysis, $^1H$, $^{13}C$ NMR, IR, Far-IR and UV-Vis spectroscopy.

• Journal of the Korean Chemical Society
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• v.46 no.4
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• pp.389-393
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• 2002

• Journal of the Korean Chemical Society
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• v.37 no.7
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• pp.655-661
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• 1993

The neutral monomeric compounds $[Mo(NO)_2Cl_2(phen)]$ and $[W(NO)_2Cl_2(phen)]$ (phen= 1,10-phenanthroline) have been prepared by reactions of polymeric compounds $[{Mo(NO)_2Cl_2}n],\;[{W(NO)_2Cl_2}n]$ with chelate ligands. Additions of one equivalent of silver(I) perchlorate to these cis-dinitrosyl compounds in acetone solution produce $[Mo(NO)_2(phen)(S)Cl][ClO_4]\;and\;[W(NO)_2(phen)(S)Cl][ClO_4]$ (S = acetone). The homo- and hetero-dinuclear complexes, $[Cl(phen)(NO)_2M(pyz)M'(NO)_2(phen)Cl][ClO_4]_2$ (M = Mo, W) and $[Cl(phen)(NO)_2M(pyz)M'(NO)_2(phen)Cl][C1O_4]_2$ (M = Mo, M' = W) have been prepared by these monocationic complexes with pyrazine ligand respectively. These complexes characterized by elemental analysis, $1^H-\;and\;^{13}C-NMR$, infrared, and UV-visible spectroscopy are reported. The spectral data indicate that homo- and hetero-dinuclear complexes were symmetrical structures of $C_{2v}$.