• 제목/요약/키워드: Schiff-base complex

검색결과 69건 처리시간 0.019초

Synthesis, Characterization and Liquid Phase Oxidation of Cyclohexane with Hydrogen Peroxide over Oxovanadium(IV) Schiff-base Tetradendate Complex Covalently Anchored to Multi-Wall Carbon Nanotubes (MWNTs)

  • Salavati-Niasari, Masoud;Bazarganipour, Mehdi
    • Bulletin of the Korean Chemical Society
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    • 제30권2호
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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.

Efficient Biomimetic Oxidative Decarboxylation of Some Carboxylic Acids Catalyzed by a Manganese (III) Schiff Base Complex

  • Nasr-Esfahani, Masoud;Montazerozohori, Morteza;Akhlaghi, Parisa
    • Bulletin of the Korean Chemical Society
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    • 제30권7호
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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.

Synthesis and Characterization of Schiff Base Metal Complexes and Reactivity Studies with Malemide Epoxy Resin

  • Lakshmi, B.;Shivananda, K.N.;Prakash, Gouda Avaji;Isloor, Arun M.;Mahendra, K.N.
    • Bulletin of the Korean Chemical Society
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    • 제33권2호
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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.

세자리 Schiff Base의 Ni(II) 착물의 분석 (Analysis of Tridentate Schiff Base Ni(II) Complex)

  • 채희남;최용국
    • 분석과학
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    • 제11권5호
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    • pp.332-340
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    • 1998
  • Salicylaldehyde와 2-hydroxy-1-naphthaldehyde를 2-aminophenol과 2-amino-p-cresol에 반응시켜 세자리 Schiff base 리간드($SIPH_2$, $SIPCH_2$, $HNIPH_2$, $HNIPCH_2$)들을 합성하였다. 이들 리간드를 Ni(II) 이온과 반응시켜 세자리 Schiff base Ni(II) 착물들을 합성 하였다. 이들 리간드와 그 착물들의 가상적인 구조와 특성을 원소분석, $^1H$-NMR, IR, UV-vis 분광법과 열 무게 분석법으로 알아보았다. Schiff base 리간드와 Ni(II) 착물의 몰비는 1:1로 결합하며, Ni(II)착물들은 3분자의 수화물이 배위된 6배위의 8면체 구조임을 알았다. 지지 전해질로서 0.1 M TBAP를 포함한 DMSO 용액에서 순환 전압전류법과 미분 펄스 전압전류법으로 세자리 Schiff base 리간드와 이들의 Ni(II) 착물들의 전기 화학적인 산화 환원 과정을 알아보았다. 세자리 Schiff base 리간드들의 전기 화학적 환원은 확산 지배적이고 비가역적으로 진행되었다. Ni(II) 착물의 전기화학적 환원과정은 1단계 1전자 반응으로 확산 지배적이고 준가역적으로 진행되었다. Ni(II) 착물들의 환원전위는 [$Ni(II)(HNIP)(H_2O)_3$]>[$Ni(II)(SIP)(H_2O)_3$]>[$Ni(II)(SIPC)(H_2O)_3$]>[$Ni(II)(HNIPC)(H_2O)_3$]순으로 양전위 방향으로 이동하였으며, 리간드의 영향은 크게 받지 않았다. 이들 결과로 부터 본 연구에서 합성한 Ni(II)착물은 [$Ni(II)(HNIPC)(H_2O)_3$] 착물이 DMSO용매에서 가장 안정함을 알 수 있다.

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세자리 Schiff Base 리간드의 Cu (II), Ni (II) 및 Zn (II) 착물에 관한 연구 (제1보) (Studies on the Cu (II), Ni (II) and Zn (II) Complexes with Tridentate Schiff Base Ligand (I))

  • 조기형
    • 대한화학회지
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    • 제18권3호
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    • pp.189-193
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    • 1974
  • 세자리 schiff base 리간드로서 salicylidene imino-o-thiobenzene은 salicylaldehyde와 o-aminothiolbenzene을 Duff reaction 시킴으로써 합성하였으며 이 리간드와 Cu(II), Ni(II), 및 Zn(II) 이온들과의 반응으로서 새로운 착물 Cu(II)$[C_{13}H_9ONS]{\cdot}3H_2O$, 및 Ni(II)$[C_{13}H_9ONS]{\cdot}3H_2O,\;Zn(II)[C_{13}H_9ONS]{\cdot}3H_2O$들을 합성하였다. 이 착물들은 가시부 자외선스펙트럼, 적외선스펙트럼, TGA, DTA 및 원소분석측정에 의하여 리간드와 금속은 1:1 몰비로 착물을 이루며 Cu(II) 착물은 1수화물 4배위 결합착물이고 Ni(II), 및 Zn(II) 착물은 3수화물, 6배위 결합의 착물임을 알아보았다.

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네자리 Schiff Base 리간드의 금속착물에 관한 연구 (Studies on the Metal Complexes with the Tetradentate Schiff Base Ligand)

  • 조기형;오상오;김찬호
    • 대한화학회지
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    • 제18권3호
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    • pp.194-201
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    • 1974
  • 네자리 schiff리간드는 salicylaldehyde와 m-phenylenediamine을 Duff-반응 시킴으로써 N,N-bis(salicylaldehyde)-m-phenylenediimine을 합성하고 이 리간드와 Cu(II), Ni(II), Co(II) 및 Zn(II) 이온들과의 새로운 착물 Cu(II)$[C_{20}H_{14}O_2N_2]{\cdot}2H_2O, Co(II)[C_{20}H_{14}O_2N_2]{\cdot}2H_2O$ 및 Zn(II)$[C_{20}H_{14}O_2N_2]{\cdot}4H_2O$들을 합성하였다. 이들 착물에 대하여 가시부 흡수스펙트럼, 적외선스펙트럼, TGA, X-ray 회절 및 원소분석 결과에 의하여 Cu(II), Ni(II) 및 Co(II) 착물들은 리간드와 금속이 1:1 몰비 및 2수화물의 6배위 착물로 주어지며 Zn(II) 착물은 1:2 몰비 4배위 착물로 주어짐을 알았다

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