• Bulletin of the Korean Chemical Society
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• v.24 no.5
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• pp.537-538
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• 2003

• Applied Chemistry for Engineering
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• v.18 no.3
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• pp.218-226
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• 2007

The stereoselective synthesis of chiral terminal epoxides is of immense academic and industrial interest due to their utility as versatile starting materials as well as chiral intermediates. In this study, new dinuclear chiral Co (salen) complexes bearing gallium-, indium- and tallium-chloride have been synthesized and characterized. The mass and EXAFS spectra provided the direct evidence of formation of dinuclear complex. Their catalytic activity and selectivity have been demonstrated for the asymmetric ring opening of various terminal epoxides having ether or ester groups by hydrolytic kinetic resolution technology. The easily prepared dimeric complexes exhibited very high enantioselectivity for the asymmetric ring opening of epoxides with $H_2O$ nucleophile, providing enantiomerically enriched terminal epoxides (> 99% ee). The dimeric structured chiral salen showed remarkably enhanced reactivity and may be employed substantially lower loadings than its monomeric analogues. The system described in this work is very efficient for the synthesis of chiral epoxide and 1,2-diol intermediates

• Journal of the Korean Chemical Society
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• v.46 no.3
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• pp.194-204
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• 2002

Aseries of novel salen-type complexes {[Mn(III)($L_{acn}$)CI]: n=1~11} containing CI- ion were obtained by reactions of the Mn(CH$_3$COO)$_2$· 4H$_2$O with the potentially tetradentate compartmental ligand {$H$_2$L_{acn}$} prepared by condensation the of one mole of diamine {ethylenediamine, 1,3-propnediamine, o-phenylenediamine and 2,2-dimethyl-1,3-propanediamine} with two moles of aldehyde {alicylaldehyde, 5-chloro-salicylaldehyde, 3,5-dichlorosalicylaldethyde, and 3,5-di-tert-butyl-2-hydroxy-benzaldehyde} in a methanol solution. The resulting salen-type lignds and their Mn(III) complexes were identified and characterized by elemental analysis, conductivity, themogravimetry and UV-VIS, IR and NMR spectroscopy.

• Applied Chemistry for Engineering
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• v.18 no.4
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• pp.330-336
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• 2007

In this study, new dinuclear chiral Co (salen) complexes bearing $BF_3$ have been synthesized and their properties as the asymmetric catalyst have been examined. The NMR, UV and ESCA analyses were performed to determine the structure of synthesized catalysts. Their catalytic activity and selectivity have been demonstrated for the asymmetric ring opening of various terminal epoxides by hydrolytic kinetic resolution technology. The easily prepared dimeric complexes exhibited very high enantioselectivity for the asymmetric ring opening of epoxides with $H_2O$ nucleophile, providing enantiomerically enriched terminal epoxides (> 99 %ee). The dimeric structured chiral salen showed remakablely enhanced reactivity and may be employed substantially lower loadings than its monomeric analogues, and in addition no racemization happened during the separation of product epoxides. The system described in this work is very efficient for the sinthesis of chiral epoxide and 1,2-diol intermediates.

• Korean Chemical Engineering Research
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• v.46 no.4
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• pp.769-776
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• 2008

The stereoselective synthesis of chiral terminal epoxide is of immense interest due to their utility as versatile starting materials as well as chiral intermediates. In this study, new chiral Co(salen) complexes bearing cobalt(II) chloride, iron(III) chloride and zinc(II) nitrate have been synthesized and characterized. The mass and EXAFS spectra provided the direct evidence of formation of complex. Their catalytic activity and selectivity have been demonstrated for the asymmetric ring opening of terminal epoxides such as styrene oxide and phenylglycidylether by hydrolytic kinetic resolution technology and for the synthesis of glycidyl buthylate. The easily prepared complexes exhibited very high enantioselectivity for the asymmetric ring opening of epoxides with $H_2O$ nucleophile, providing enantiomerically enriched terminal epoxides (>99% ee). The newly synthesized chiral salen showed remakablely enhanced reactivity with substantially low loadings. The system described in this work is very efficient for the sinthesis of chiral epoxide and 1,2-diol intermediates.

• Journal of Applied Biological Chemistry
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• v.48 no.2
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• pp.105-107
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• 2005

• Bulletin of the Korean Chemical Society
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• v.19 no.7
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• pp.726-728
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• 1998

• Bulletin of the Korean Chemical Society
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• v.18 no.8
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• pp.796-798
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• 1997

• Bulletin of the Korean Chemical Society
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• v.20 no.8
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• pp.867-868
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• 1999

• Proceedings of the Membrane Society of Korea Conference
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• 1997.10a
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• pp.21-24
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• 1997

1.서론 : 산소선택성이 좋은 투과막은 산소부화에 의한 연소효율의 향상, 간이 산소발생장치에의 응용 등 여러가지의 용도가 예상된다. 이를 위한 준비단계로 막소재 및 막형상에 대한 검토가 \ulcorner발하게 진행되고 있다. 그 중에서 높은 산소선택성을 발현하는 방법이 주목되어지고 있는데 이는 가역적 산소흡탈착능을 갖는 carrier분자를 이용한 촉지운송계(facilitated transport system)를 구축하는 방법이 있다. 본 연구에서는 [Co(salen)]과 같은 $N_2O_2$형 평면정방착제(Square planar complex)이며, salen의 shift염기부분을 bipyridine cycle, phenoxide부분을 해리한 amide로 골격변환한 구조를 갖고 있는 6,6'-bis(benzoylamino)-2,2'-bipyridine(babpH$_2$)의 covalt착체([Co(babp)]를 배위결합에 의해 고분자막중에 고정하고, 산소흡탈착능, 산소투과성, 안정성 등을 검토하는 것을 바탕으로 우수한 선택성 산소투과막을 개발하는 것을 목적으로 한다.