• 대한화학회지
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• 제38권4호
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• pp.319-327
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• 1994

질소원자를 네 개 또는 다섯 개 가지는 트리에틸렌테트라아민과 테트라에틸렌펜타아민에 살리실알데히드를 각각 반응시켜 황갈색 액체상의 여섯자리 배위자리를 가지는 새로운 시프 염기 리간드인 비스(살리실알데히드)-트리에틸렌테트라아민(BSTT)과 일곱자리 시프 염기인 비스(살리실알데히드)-테트라에틸렌펜타아민(BSTP)을 합성하고, 다시 이들 액체상의 시프 염기에 아세트산과 진한 염산을 가하여, pH4.0의 특정한 농도하에서 연노란색의 염산염 시프 염기들의 결정을 얻었다. 또한 이들 시프 염기 리간드와 구리(Ⅱ)를 반응시켜 새로운 시프 염기-구리(Ⅱ)착물을 합성하여 여러가지 물리적 및 화학적 성질에서부터 가능한 이들 화합물의 구조를 제안하였다.

• 대한화학회지
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• 제63권1호
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• pp.29-36
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• 2019

A potentially tetradentate Schiff base ligand, 2-((2-((pyridin-2-ylmethylene)amino)ethyl)amino)ethan-1-ol (PMAE), and its cadmium(II) complex, [$Cd(PMAE)I_2$] (1), were prepared and characterized by elemental analysis, FT-IR, Raman, $^1H$ and $^{13}C$ NMR spectroscopies and single-crystal X-ray diffraction. In the crystal structure of 1, the cadmium atom has a slightly distorted square-pyramidal geometry and a $CdN_3I_2$ environment in which the PMAE acts as an $N_3$-donor. In the crystal packing of the complex, the alcohol and amine groups of the coordinated ligands participate in hydrogen bonding with iodide ions and form $R^2{_2}(14)$ and $R^2{_2}(8)$ hydrogen bond motifs, respectively. In addition to the hydrogen bonds, the crystal network is stabilized by ${\pi}-{\pi}$ stacking interactions between pyridine rings. The thermodynamic stability of the isolated ligand and its cadmium complex along with their charge distribution patterns were studied by DFT and NBO analysis.

• 대한화학회지
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• 제39권7호
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• pp.538-542
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• 1995

Hydrazide schiff base 리간드인 N,N'-oxalylbis(salicylalde hydehydrazone)(OBSH)과 N,N'-malonylbis(salicylaldehydehydrazone)(MBSH), N,N'-succinylbis(salicylaldehydehydrazone)(SBSH) 리간드들과 $UO_2^{2+}$ 이온과의 착물형성에 따르는 안정도상수와 열역학적 파라미터를 95% DMF 용액에서 전위차 적정법을 사용하여 측정하였다. 안정도상수의 크기는 SBSH$UO_2^{2+}$ 이온과의 착물형성에 대한 ΔH는 OBSH에 대해서는 음의 값을 갖는 발열반응임을 알 수 있었고, MBSH, SBSH에 대해서는 양의 값을 갖는 흡열반응임을 알 수 있었다. ΔS는 OBSH < MBSH < SBSH로 증가하였다.

• Bulletin of the Korean Chemical Society
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• 제34권11호
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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.

• 대한화학회지
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• 제18권4호
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• pp.267-271
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• 1974

네자리 schiff base 리간드로서 N,N-비스(살리실알데히드)에틸렌디이민과 Mo(IV), Mo(V), Mo(VI) 및 Mo(III)의 각 산화상태인 몰리브덴이온들과의 반응으로서 새로운 착물$[MoO_2(C_{16}H_{14}O_2-N_2)], [MoO(C_{16}H_{14}O_2N_2)]_2O, (Mo(SCN)(C_{16}H_{14}O_2N_2)]_2O$들을 합성하였다. 이들 착물들은 리간드와 몰리브덴의 몰비가 1:1이며, 6배위의 가상적인 구조로 주어짐을 원소 분석치와 가시부 및 적외선 흡수스펙트럼, T.G.A., D.T.A. 및 X-ray 회절의 고찰로서 알아보았다.

• 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.

• Bulletin of the Korean Chemical Society
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• 제17권8호
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• pp.688-693
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• 1996

Tetradentate Schiff base ligands derived from 2-hydroxy-1-naphthaldehyde and aliphatic diamine have been synthesized. Cu(Ⅱ) complexes of Schiff base ligands have been synthesized from the free ligands and copper acetate. The mole ratio of ligand to copper was identified to be 1:1 by the result of elemental analysis and Cu(Ⅱ) complexes were in a four-coordinated configuration. The electrochemical redox process of Cu(Ⅱ) complexes in a DMF solution has been investigated by cyclic voltammetry, chronoamperometry, differential pulse voltammetry, and controlled potential coulometry. The redox process of Cu(Ⅱ) complexes is one electron transfer process in quasi-reversible and diffusion-controlled reaction. The electrochemical redox potentials and the kinetic parameters of Cu(Ⅱ) complexes are affected by the chelate ring of Schiff base ligands.

• 대한화학회지
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• 제52권4호
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• pp.439-444
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• 2008

• Journal of Electrochemical Science and Technology
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• 제8권3호
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• pp.222-235
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• 2017

First, in this study, the inhibition efficiencies of metal complexes with Cu(II), Ni(II) and Zn(II) of STSC ligand for corrosion control of mild steel in oilfield formation water were investigated. The IEs for a mixture of 500 ppm STSC and 5 ppm metal ion ($Cu^{+2}$, $Ni^{+2}$, $Zn^{+2}$) were found to be 88.77, 87.96 and 85.13 %, respectively. The results were obtained from the electrochemical techniques such as open circuit potential, linear and tafel polarization methods. The polarization studies have showed that all used Schiff base metal complexes are anodic inhibitors. The protective film has been analyzed by FTIR technique. Also, to detect the presence of the iron-inhibitor complex, UV-Visible spectral analysis technique was used. The inhibitive effect was attributed to the formation of insoluble complex adsorbed on the mild steel surface and the adsorption process follows Langmuir adsorption isotherm. The surface morphology has been analyzed by SEM. Secondly, the computational studies of the ligand and its metal complexes were performed using DFT (B3LYP) method with the $6-311G^{{\ast}{\ast}}$ basis set. Finally, it is found that the experimental results were closely related to theoretical ones.

• Bulletin of the Korean Chemical Society
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• 제35권1호
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• pp.269-272
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• 2014