• Journal of the Korean Chemical Society
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• v.18 no.3
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• pp.194-201
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• 1974

The tetradentate schiff base ligand, N,N'-bis(salicylaldehyde)-m-phenylenediimine has been prepared from salicylaldehyde and m-phenylenediamine by Duff-reaction. The schiff base ligand has been reacted with Cu(II), Ni(II), Co(II), and Zn(II) to form new complexes; Cu(II)$[C_{20}H_{14}O_2N_2]{\cdot}2H_2O, Ni(II)[C_{20}H_{14}O_2N_2]{\cdot}2H_2O, Co(III)[C_{20}H_{14}O_2N_2]{\cdot}2H_2O and Zn(II)2[C_{20}H_{14}O_2N_2]{\cdot}4H_2O$. It seems to be that the Cu(II), Ni(II) and Co(II) complexes have hexacoordinated configuration with the schiff base and two molecules of water, while Zn(II) complex has tetracoordinated configuration with the schiff base and four molecules of water. The mole ratio of tetradentate schiff base ligand to Cu(II), Ni(II) and Co(II) are 1:1 but to Zn(II) is 1:2. These complexes have been identified by visible spectra, infrared spectra, T.G.A. and elemental analysis.

• Bulletin of the Korean Chemical Society
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• v.28 no.1
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• pp.133-135
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• 2007

• Journal of the Korean Chemical Society
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• v.53 no.6
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• pp.693-703
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• 2009

The complex formation of anti-inflamatory drug piroxicam (PX, 4-hydroxy-2-methyl-N-2--pridyl-2H-1,2-benzothiazine-3-carboxadiamide-1,1-dioxide) with transition metal ions Co(II), Ni(II), Cu(II) and Zn(II) in methanol(MeOH)/water binary mixtures were studied by spectrophotometric method at 25$^{\circ}C$, constant pH = 5.0 and I = 0.1 M. The computer program SQUAD was used to extract the desired information from the spectral data. The outputs of the fitting processes were stability constants, standard deviations of the estimated stability constants, concentration distribution diagrams and spectral profiles of all species. The sequence of the stability constants of PX complexes with Co(II), Ni(II), Cu(II) and Zn(II) follow the Cu(II) > Co(II) > Ni(II) ${\approx}$ Zn(II) order. This may be due to different geometry tendencies of these metal ions. The acidity constants of the PX were also determined under above condition from its absorption spectra at different pH values. The computer program DATAN was used for determination of acidity constants of PX. The validity of the obtained acidity constants was checked by a well known computer program SPECFIT/32. The effects of the different parameters like solvent nature, cations characteristics on the stability and acidity constants were thoroughly discussed.

• The Korean Journal of Pesticide Science
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• v.4 no.1
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• pp.32-37
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• 2000

A series of transition metal complexes of 3,6-bis(6'-methyl-2'-pyridyl)pyridazine ($L^{1}$) and 3,6-bis(2'-pyridyl)pyridazine ($L^{2}$) as artificial nuclease, $1{\sim}8$ were synthesized. After determining of X-ray crystal structure, hydrolysis rate constants of phosphates, as DNA model compound and biological activities were confirmed. $L^{2}$-Zn(II) complex, 8 was shown the best hydrolysis rate constant. The $L^{2}$-Ni(II) complex, 5 and $L^{2}$-Co(II) complex, 6 showed the highest herbicidal activity against SCP (Scriptus Juncoids) with excellent tolerance to rice, ORY (Oryzae sativa L.). And the $L^{1}$-Co(II) complex, 2, $L^{1}$-Zn(II) complex, 4 and ligand ($L^{1}$ amp; $L^{2}$) displayed above 90% fungicidal activity against MAG (Magnaporthe grisea).

• Bulletin of the Korean Chemical Society
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• v.28 no.1
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• pp.33-40
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• 2007

We have designed and synthesized three Zn(II)-porphyrin derivatives, such as Zn(II) porphyrin ([G-0]Zn-P1) and aryl ether-typed dendron substituted Zn(II)-porphyrin derivatives ([G-1]Zn-P1 and [G-1]Zn-P-CN1). Their chemical structures were characterized by 1H-NMR, FT-IR, UV-vis absorption, EI-mass, and MALDI-TOF mass spectroscopies. Their electrochemical properties were studied by cyclic voltammetry measurement. These Zn(II)-porphyrin derivatives have been used to fabricate dye-sensitized solar cells (DSSCs) based on solid polymeric electrolytes as dye sensitizers and their device performances were evaluated by comparing with that of a standard Ru(II) complex dye. [G-1]Zn-P-CN1 showed the enhanced power conversion efficiency than those of other porphyrin derivatives, as expected. Short-circuit photocurrent density (Jsc), open-circuit voltage (Voc), fill factor (FF), and power conversion efficiency (η) of solid-typed DSSC for [G-1]Zn-P-CN1 were evaluated to be Jsc = 11.67 mA/cm2, Voc = 0.51 V, FF = 0.46, and η = 2.76%, respectively.

• Journal of the Korean Chemical Society
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• v.32 no.1
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• pp.30-36
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• 1988

The effect of high pressure on the stability of copper(II), cadmium(II) and zinc (II) complex ions with ethylenediamine, propylenediamine, diethylenetriamine has been investigated polarographically. 0.10M KN$O_3$ solution was used as a supporting electrolyte. The concentration of chelating agents was varied from 0.01M to 1.00M. The dissociation constants of metal complex ions were increased with increasing the pressure from 1 atmosphere to 1,500 atmospheres. The increment of the dissociation constant per unit atmosphere varied from 1.1 ${\times} 10^{-3}$% for Cu(dien)$_2^{2+}$ to 5.0 ${\times} 10^{-3}$ % for Zn(en)$_2^{2+}$.

• Bulletin of the Korean Chemical Society
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• v.35 no.6
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• pp.1697-1702
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• 2014

A novel complex [$Zn(phen)(o-AB)_2$] [phen: 1,10-phenanthroline o-AB: o-aminobenzoic acid] was synthesized and characterized by elemental analysis and X-ray diffraction single-crystal analysis. The crystal crystallizes in monoclinic, space group P2(1)/c with $a=7.6397(6){\AA}$, $b=16.8761(18){\AA}$, $c=17.7713(19){\AA}$, ${\alpha}=90^{\circ}$, ${\beta}=98.9570(10)^{\circ}$, ${\gamma}=90^{\circ}$, $V=2.2633(4)nm^3$, Z = 4, F(000) = 1064, S = 1.058, $Dc=1.520g{\cdot}cm^{-3}$, $R_1=0.0412$, $wR_2=0.0948$, ${\mu}=1.128mm^{-1}$. The Zn(II) is six coordinated by two nitrogen and four oxygen atoms from the 1,10-phenanthroline and o-aminobenzoic acid to furnish a distorted octahedron geometry. The complex exhibits intense fluorescence at room temperature. Theoretical studies of the title complex were carried out by density functional theory (DFT) B3LYP method. CCDC: 898291.

• Analytical Science and Technology
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• v.11 no.6
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• pp.440-447
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• 1998

Polydentate Schiff base ligands 5-Br-BSDT(bis(5-bromosalicylaldehyde)diethylenetriamine) having $N_3O_2$ atoms, 5-Br-BSTT(bis(5-bromosalicylaldehyde)triethylenetetramine) having $N_3O_2$ atoms, 5-Br-BSTP(bis(5-bromosalicylaldehyde)tetraethylenepentamine) having $N_3O_2$ atoms were synthesized. Stability constants of the complexes between these ligands and the metal ions such as Cu(II), Ni(II) and Zn(II) were measured in DMSO by a polarographic method. It was observed that all metal(II) ions employed in this study formed 1 : 1 complexes with Schiff base ligands. Stability constants for the ligands were in the order of Cu(II)>Ni(II)>Zn(II), and for complex formation were in the order of 5-Br-BSTP>5-Br-BSTT>5-Br-BSDT according to the increasing in the number of donor atoms. Both enthalpy and entropy changes are obtained in negative valves. Exothermicity for the complex formation indicated tight binding between the ligands and metal ions. The negative entropy change would be related to the fact that solvent molecules are strongly interacting with the metal complexes.

• Korean Journal of Crystallography
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• v.11 no.1
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• pp.42-45
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• 2000

The complex [Zn(L)Cl](H₂O)(ClO₄) (1) (L=3,14-dimethyl-2,6,13,17-tetraazatricyclo[14,4,O/sup 1.18/,O/sup 7.12/]docosane) has been prepared and characterized by X-ray crystallography. 1 crystallizes in the monoclinic space group P2₁/c, with a=8.883(1), b=19.319(9), c=15.124(2)Å, β=101.65(1)°, V=2542.0(13) ų, Z=4, R₁(wR₂) for 4457 observed reflections of [I>2σ(I)] was 0.0640(0.1557). The coordination geometry around the zinc is a distorted square-pyramid with four nitrogen atoms of the macrocycle occupying the basal sites(Zn-N/sub av/=2.131(2)Å) and a chloride atom at the axial position with the Zn-Cl distance of 2.315(2)Å.

• Bulletin of the Korean Chemical Society
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• v.32 no.8
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• pp.2617-2622
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• 2011

Two new Zn(II) complexes, $[Zn_2(dpa)_2(phen)_2(H_2O)_2]{\cdot}H_2O$ (1) (dpa = dephenate, phen = 1,10-phenanthroline) and [$Zn_2(dpa)_2(bpy)_2(H_2O)_2$] (2) (bpy = 2,2'-bipyridine) 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 zinc(II) complexes bridged by dpa dianions, respectively. The zinc ions in 1 exhibit a distorted square pyramidal environments, while the zinc ions in 2 exhibit a trigonal bipyramid geometry. In each complex, the dpa ligand is coordinated to zinc ions as a bis-monodentate.