• Bulletin of the Korean Chemical Society
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• 제25권12호
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• pp.1757-1763
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• 2004

A new series of nickel(II), cobalt(II)/(III) and copper(II) complexes of 14, 15 and 16-membered of macrocyclic ligands have been prepared and characterized by elemental analyses, IR, UV-VIS and $^1H-NMR$ spectra, magnetic susceptibilities, conductivities, DTA and ESR measurements. Molar conductances in DMF solution indicate that, the complexes are nonelectrolytes except (9-12) complexes. The electronic spectra show that, all complexes are square planar or distorted octahedral geometry. The ESR spectra of solid complexes (4), (8) and (11) show square planar of axial type symmetry $(d_{x2-y2})$ with considerable covalent bond character. However, complex (12) shows a spectrum of octahedral geometry with $d_{z2}$ ground state. Complex (12) shows exploitation in reducing the amount of electron adducts formed in DNA during irradiation with low radiation products.

• Bulletin of the Korean Chemical Society
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• 제7권5호
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• pp.338-341
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• 1986

Hydrocarbon solution of $Ir(PPh_3)_2(CO)OClO_3$ reacts with $Ph_2PC_6H_4$-o-CHO and 3-methyl-2-aminopyridinyl aldimine to yield ${\bar{Ir(Ph_2PC_6H_4-o-CO)}}\;(PPh_3)_2(CO)(H)ClO_4$(1) and ${\bar{Ir(NC_6H_6NC}}C_6H_5)(PPh_3)_2(CO)(H)ClO_4$(2), respectively. The compound $Ir(PPh_3)_2N_2Cl$ also reacts with $Ph_2PC_6H_4$-o-CHO and 3-methyl-2-aminopyridinyl aldimine to give ${\bar{Ir(Ph_2PC_6H_4-o-C}}O)(PPh_3)_2(H)Cl(3)$ and $Ir(NC_6H_5NCC_6H_5(PPh_3)_2(H)Cl(4)$, respectively. Compounds 1, 2, 3, and 4 were characterized by infrared, $^1H$ NMR, $^{31}p$ NMR, UV spectra, and conductivity measurements.

• Bulletin of the Korean Chemical Society
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• 제24권9호
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• pp.1313-1318
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• 2003

A series of complexes of bivalent transition metal ions with acetyl benzal dehydehydrazone and its derivatives of general formula ML have been prepared and characterized with the help of conductometric, photometric and infrared studies. The stability constants and related thermodynamic functions of complexes were determined using the potentiometric technique at different temperatures. The formation of complexes is exothermic process with covalency nature. The electrical conductivity of some solid complexes was measured in the temperature range 289-353 K. The results revealed semiconducting properties for the studied complexes.

• Bulletin of the Korean Chemical Society
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• 제12권2호
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• pp.130-137
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• 1991

The following new cryptand 221 complexes of lanthanides(Ⅲ) and dioxouranium(Ⅵ) nitrate have been synthesized: $(Ln(C_{16}H_{32}N_2O_5)(H_2O)_2(NO_3)_3\ and \((UO_2)_2(C_{16}H_{32}N_2O_5)(H_2O)_4(NO_3)_4$. These complexes have been identified by elemental analysis, moisture titration, conductivity measurements and various spectroscopic techniques. The proton and carbon-13 NMR as well as calorimetric measurements were used to study the interaction of cryptand 221 with La(Ⅲ), Pr(Ⅲ ), Ho(Ⅲ) and $UO_2(Ⅱ)$ ions in nonaqueous solvents. The bands of metal-oxygen atoms, metal-nitrogen atoms and O-U-O in the IR spectra shift upon complexation to lower frequencies, and the vibrational spectra ({\delta}NMN$) of metal-amide complexes in the crystalline state exhibit lattice vibrations below 300 $cm^{-1}$. The NMR spectra of the lanthanides(Ⅲ) and dioxouranium(Ⅵ) nitrate complexes in nonaqueous solvents are quite different, indicating that the ligand exists in different conformation, and also the $^1H$ and $^{13}C-NMR$ studies indicated that the nitrogen atom of the ring has greater affinity to metal ions than does the oxygen atom, and the planalities of the ring are lost by complexation with metal ions. Calorimetric measurements show that cryptand 221 forms more stable complexes with $La^{3+}$ and $Pr^{3+}$ ions than with $UO^{22+}$ ion, and $La^{3+}/Pr^{3+}$ and $UO^{22+}/Pr^{3+}$ selectivity depends on the solvents. These changes on the stabilities are dependent on the basicity of the ligand and the size of the metal ions. The absorption band (230-260 nm) of the complex which arises from the direct interaction of macrocyclic donor atoms with the metal ion is due to n-{\delta}*$ transition and also that (640-675 nm) of $UO^{22+}$-cryptand 221 complex, which arises from interaction between two-dioxouranium(Ⅵ) ions in being out of cavity of the ligand ring is due to d-d* transition.

• 대한화학회지
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• 제54권4호
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• pp.402-410
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• 2010

새로운 착물인 cis-[$Mo_2O_3(Hapdhba)_2$], trans-[$UO_2(Hapdhba)_2$], [Pd(Hapdhba)Cl($H_2O$)], [Pd(bpy)(Hapdhba)]Cl, [Ag(bpy) (Hapdhba)], [$Ru(Hapdhba)_2(H_2O)_2$], [$Rh(Hapdhba)_2Cl(H_2O)$] 및 [Au(Hapdhba)$Cl_2$]를 보고한다. 여기서 $H_2$apdhba는 2-aminopyrimidine 및 2,4-dihydoxybenzaldehyde에서 비롯된 Schiff-염기이다. 이들 착물은 IR, UV-Vis 그리고 질량 스펙트럼을 비롯하여 전기전도도, 자기 및 열 분석을 통해 특성을 조사하였다. 구리의 부식에 대한 $H_2$apdhba의 방해효과는 0.5 M HCl에서 potiodynamic polarization 측정을 통해 조사하였다.

• 대한화학회지
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• 제59권3호
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• pp.215-224
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• 2015

Unsymmetrical tetradentate Schiff base N-(2-hydroxy-5-methylacetophenone)-N'-(2-hydroxy acetophenone) ethylene diamine (H₂L) and its complexes with Cr(III), Mn(II), Fe(III), Co(II), Ni(II) and Cu(II) have been synthesized and characterized by elemental analyses, magnetic susceptibility measurements, IR, electronic spectra and thermogravimetric analyses. ¹H, ¹³C-NMR and FAB Mass spectra of ligand clearly indicate the presence of OH and azomethine groups. Elemental analyses of the complexes indicate that the metal to ligand ratio is 1:1 in all complexes. Infrared spectra of complexes indicate a dibasic quadridentate nature of the ligand and its coordination to metal ions through phenolic oxygen and azomethine nitrogen atoms. The thermal behavior of these complexes showed the loss of lattice water in the first step followed by decomposition of the ligand in subsequent steps. The thermal data have also been analyzed for the kinetic parameters by using Horowitz-Metzger method. The dependence of the electrical conductivity on the temperature has been studied over the temperature range 313-403 K and the complexes are found to show semiconducting behavior. XRD and SEM images of some representative complexes have been recorded. The antimicrobial activity of the ligand and its complexes has been screened against various microorganisms and all of them were found to be active against the test organisms. The Fe(III) and Ni(II) complex have been tested for the catalytic oxidation of styrene.

• 대한화학회지
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• 제47권3호
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• pp.199-205
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• 2003

우라닐 이온, $UO^+_2$와 Schiff-base 와의 착화합물이 글리실글라이신과 살리실알데히드, 2-히드록시-1-나프트알데히드, 2,3-디히드록시 벤즈알데히드 그리고 2,4-디히드록시 벤즈알데히드와의 축합에 의해 합성되었으며 이들 착화합물의 특성을 원소분석, 전도도 측정, 자기화율 측정, UV, IR, NMR 스펙트라와 DTA, TG, DSC 결과를 이용하여 조사하였다. 구조와 열분해 메카니즘이 제안되었다.

• Bulletin of the Korean Chemical Society
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• 제15권6호
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• pp.465-468
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• 1994

The charge transfer compounds $(TTF)_4FeCl_3{\cdot}CH_3OH,\;(TTF)_4SbCl_4\;and\;(TTF)_5(SbBr_4)_2{\cdot}CH_3COCH_3$ were prepared from reactions of the TTF (tetrathiafulvalene) and metal halides. The compounds were characterized by spectroscopic (UV,IR, EPR and XPS) methods, magnetic susceptibility and electrical conductivity measurements. The d.c electrical conductivities of the pressed pellets are in the order of $10^{-1}-10^{-3} Scm^{-1}$, which lies in the range of semiconductor region at room temperature. It means that the partially ionized TTF has stacked in low-dimensional chain in each compound. Spectroscopic properties also indicate that TTF molecules are partially ionized and charge transfer has occurred from (TTF)n to Fe(III) center in $(TTF)_4FeCl_3{\cdot}CH_3OH$ whereas to the $-SbX_4^-$ entity in $(TTF)_4SbCl_4\;and\;(TTF)_5(SbBr_4)_2{\cdot}CH_3COCH_3$. The EPR g values are consistent with TTF radical formation and EPR linewidths suggest the delocalization of unpaired electrons along TTF stacks. A signal arised from metal (Fe and Sb) ions were not detected in EPR spectra, indicating that metal ion is in the diamagnetic state in each compound. The diamagnetic state was also examined by the magnetic susceptibility measurement. The magnetic properties reveal the significant interaction between the $TTF^+$ radical cations in the stacks. The oxidation state of metal ions was also investigated by XPS spectra.

• 대한화학회지
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• 제58권2호
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• pp.169-178
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• 2014

A new series of metal complexes of V(IV), Pd(II), Pt(IV), Ce(IV) and U(VI) with 3-[(3-chlorophenyl)-hydrazono]-pentane-2,4-dione (Cphpd) were synthesized and characterized by elemental analysis, molar conductivity, magnetic moment measurements, UV-vis, FT-IR and $^1H$ NMR as well as TG-DTG techniques. The data indicated that the Cphpd acts as a bidentate ligand through the hydrazono nitrogen and one keto oxygen. The kinetic parameters have been evaluated by using Coats Redfern (CR) and Horowitz-Metzeger (HM) methods. The thermodynamic data reflected the thermal stability for all complexes. The calculated bond length and the bond stretching force constant, F(U=O), values for $UO_2$ bond are $0.775{\AA}$ and $286.95Nm^{-1}$. The bond lengths, bond angles, dipole moment and the lowest energy model structure of the complexes have been determined with DFT calculations. The antimicrobial activity of the synthesized ligand and its complexes were screened.

• 대한화학회지
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• 제55권1호
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• pp.19-27
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• 2011

2-(Benzothiazol-2-yl)-N'-(2,5-dihydroxybenzylidene)acetohydrazide 에대한새로운일련의 Mn(II), Ni(II), Co(II), Cu(II) 및 Zn(II) 착물을 합성하여 그 특성을 원소분석, IR, UV-vis, $^1H$-NMR, 질량분석, ESR, 자기수자율 및 몰 전기전도도 측정에 의하여 조사하였다. 이들 착물의 기하구조가 사각평면 또는 팔면체임을 분광학적 데이터 및 자기적 측정으로부터 알았다. 이 리간드와 해당착물의 세균에(Aspergillus nigar 및 Fusarium oxysporium) 대한생물학적활성을 조사하였다. 그 결과, 금속착물들은 리간드 및 금속이온 모두에 비해 더 큰 활성을 나타내었다.