• Bulletin of the Korean Chemical Society
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• v.30 no.2
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• pp.355-362
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• 2009

The chemical modification of multi-wall carbon nanotubes (MWNTs) is an emerging area in material science. In the present study, hydroxyl functionalized oxovanadium(IV) Schiff-base; N,N'-bis(4-hydroxysalicylidene)-ethylene-1, 2-diamineoxovanadium(IV), [VO($(OH)_2$-salen)]; has been covalently anchored on modified MWNTs. The new modified MWNTs ([VO($(OH)_2$-salen)]-MWNTs]) have been characterized by transmission electron microscopy (TEM), X-ray diffraction (XRD), X-ray photoelectron (XPS), UV-Vis, Diffuse reflectance (DRS), FT-IR spectroscopy and elemental analysis. The analytical data indicated a composition corresponding to the mononuclear complex of tetradentate Schiff-base ligand. The characterization of the data showed the absence of extraneous complex, retention of MWNTs and covalently anchored on modified MWNTs. Liquid-phase oxidation of cyclohexane with $H_2O_2$ to a mixture of cyclohexanone, cyclohexanol and cyclohexane-1,2-diol in $CH_3$CN have been reported using oxovanadium(IV) Schiff-base complex covalently anchored on modified MWNTs as catalysts. This catalyst is more selective toward cyclohexanol formation.

• Bulletin of the Korean Chemical Society
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• v.32 no.5
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• pp.1729-1732
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• 2011

• Journal of the Korean Chemical Society
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• v.59 no.1
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• pp.103-107
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• 2015

• Bulletin of the Korean Chemical Society
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• v.30 no.7
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• pp.1583-1587
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• 2009

The four dentate $N_2O_2$ Schiff base ligand of bis(2-hydroxyacetophenone)-1,2-propanediimine (BHAPN) and its manganese (III) complex were synthesized and identified by microanalysis, spectral data ($^1H$ NMR, MS, FT-IR and UV-Visible) and molar conductivity measurement. The mild and efficient homogeneous oxidative decarboxylation of some carboxylic acids by catalytic amount of this manganese (III) complex, using tetrabutylamonium periodate as a mild oxidant in chloroform at room temperature is reported. The catalyst used in this study showed good activity for the decarboxylation of the titled compounds.

• Bulletin of the Korean Chemical Society
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• v.33 no.2
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• pp.473-482
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• 2012

A novel malemide epoxy containing Co(II), Ni(II) and Cu(II) ions have been synthesized by curing malemide epoxy resin (MIEB-13) and Co(II), Ni(II) and Cu(II) complexes of macrocyclic bis-hydrazone Schiff base. The Schiff base was synthesized by reacting 1,4-dicarbnyl phenyl dihydrazide with 2,6-diformyl-4-methyl phenol. The Schiff base and its Co(II), Ni(II) and Cu(II) complexes have been characterized by elemental analyses, spectral (IR, $^1H$ NMR, UV-vis., FAB mass, ESR), thermal and magnetic data. The curing reaction of maleimide epoxy compound with metal complexes was studied as curing agents. The stability of cured samples was studied by thermo-gravimetric analyses and which have excellent chemical (acid/alkali/solvent) and water absorption resistance. Further, the scanning electron microscopy (SEM) and definitional scanning colorimetric (DSC) techniques were confirmed the phase homogeneity of the cured systems.

• Analytical Science and Technology
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• v.11 no.5
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• pp.332-340
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• 1998

Tridentate Schiff base ligands, $SIPH_2$, $SIPCH_2$, $HNIPH_2$, and $HNIPCH_2$ were prepared by the reactions of salicylaldehyde and 2-hydroxy-1-naphthaldehyde with 2-aminophenol and 2-amino-p-cresol. Ni(II) complexes of those ligands were synthesized. The structures and properties of ligands and their complexes were studied by elemental analysis, $^1H$-NMR, IR, UV-visible spectra, and thermogravimetric analysis. The mole ratio of Schiff base to the metal of complexes was found to be 1:1. Ni(II) complexes were contemplated to be hexa-coordinated octahedral configuration containing three water molecules. The redox process of ligands and complexes in DMSO solution containing 0.1 M TBAP as supporting electrolyte was investigated by cyclic voltammetry and differential pulse voltammetry with glassy carbon electrode. The redox process of the tridentate Schiff base ligands was totally irreversible. The redox process of Ni(II) complexes were quasi-reversible and diffusion-controlled as one electron by one step process Ni(II)/Ni(I). The reduction potentials of the Ni(II) complexes shifted in the positive direction in the order [$Ni(II)(HNIP)(H_2O)_3$]>[$Ni(II)(SIP)(H_2O)_3$]>[$Ni(II)(SIPC)(H_2O)_3$]>[$Ni(II)(HNIPC)(H_2O)_3$] and their dependence on ligands were not so high. Consequently the [$Ni(II)(HNIPC)(H_2O)_3$] complex among the synthesized Ni(II) complexes was found to be most stable in the DMSO solution.

• Bulletin of the Korean Chemical Society
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• v.27 no.5
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• pp.765-768
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• 2006

• Bulletin of the Korean Chemical Society
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• v.26 no.3
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• pp.454-456
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• 2005

• Journal of the Korean Chemical Society
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• v.18 no.3
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• pp.189-193
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• 1974

The tridentate schiff base, salicylidene imino-o-thiolbenzene, has been synthetized from salicylaldehyde and o-amino thiolbenzene by Duff reaction. The schiff base has been reacted with Cu(II), Ni(II), and Zn(II), to form new complexes; Cu(II)$[C_{13}H_9ONS]{\cdot}3H_2O$, Ni(II)$[C_{13}H_9ONS]{\cdot}3H_2O,\;Zn(II)[C_{13}H_9ONS]{\cdot}3H_2O$ It appears that the Cu(II)-complex has tetra-coordinated configuration with the schiff base and one molecule of water, while the Ni(II) and Zn(II)-complexes have hexacoordinated configuration with the schiff base and three molecules of water. The mole ratio of tridentate schiff base ligand to metals was 1:1. These complexes have been identified by infrared spectra, visible spectra, TGA, DTA and elemental analysis.

• 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.