• 한국진공학회:학술대회논문집
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• 한국진공학회 2011년도 제41회 하계 정기 학술대회 초록집
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• pp.199-199
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• 2011

The addition of a carbanion to ${\yen}{\acute{a}}{\yen}{\hat{a}}$-unsaturated carbonyl compounds is of importance in the C-C bond formation reactions for modern pharmaceuticals and organic synthesis. Recently, heterogeneous asymmetric catalysis became more attractive area of research because of the easy recovery and separation of the catalyst from the reaction system. Most of synthetic methods for heterogeneous catalysts were grafting or immobilization of homogeneous catalyst onto the solid supports. Trans-1,2-Diaminocyclohexane(DACH) and L-proline ligands have been enormously used as chiral ligands in several catalytic transformation under homogenous conditions. Our group prepared l-proline functionalized mesoporous silica was synthesized under acidic condition using a poly(ethylene oxide)-poly(propylene oxide)-poly(ethylene oxide) triblock copolymer template (EO20PO70EO20, Pluronic P-123, BASF). Furthermore, we successfully directly synthesized trans-1,2 diaminocyclohexane functionalized mesoporous silica by using microwave method. The direct functionalization of chiral ligand into the framework of mesoporous materials is expected to be useful for the heterogeneous asymmetric catalysis. So, we adopt the direct synthesis of chiral ligand functionalized mesoporous silica by using thermal and microwave irradiation. Then, chiral ligand functionalized mesoporous silicas were applied to enantioselective asymmetric catalytic reactions.

• Bulletin of the Korean Chemical Society
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• 제26권4호
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• pp.515-522
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• 2005

Enzyme-metal combo catalysis is described as a useful methodology for the synthesis of optically active compounds. The key point of the method is the use of enzyme and metal in combination as the catalysts for the complete transformation of racemic substrates to single enantiomeric products through dynamic kinetic resolution (DKR). In this approach, enzyme acts as an enantioselective resolving catalyst and metal does as a racemizing catalyst for the efficient DKR. Three kinds of enzyme-metal combinations - lipase-ruthenium, subtilisin-ruthenium, and lipase-palladium –have been developed as the catalysts for the DKRs of racemic alcohols, esters, and amines. The scope of the combination catalysts can be extended to the asymmetric transformations of ketones, enol acetates, and ketoximes via the DKRs. In most cases studied, enzyme-metal combo catalysis provided enantiomerically-enriched products in high yields.

• Bulletin of the Korean Chemical Society
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• 제34권12호
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• pp.3891-3894
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• 2013

• 통합자연과학논문집
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• 제8권2호
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• pp.107-110
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• 2015

Amino acid-catalyzed directed asymmetric aldol reactions showed enhanced enantioselectivity when conducted in ionic liquids. Optically active products were afforded in better yields (up to 23% higher) and enantiomeric excess (up to 21% higher) in ionic liquids than in conventional organic solvents.

• Bulletin of the Korean Chemical Society
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• 제33권10호
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• pp.3171-3172
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• 2012

• Bulletin of the Korean Chemical Society
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• 제33권11호
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• pp.3537-3538
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• 2012

• Bulletin of the Korean Chemical Society
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• 제30권11호
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• pp.2519-2520
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• 2009

• Bulletin of the Korean Chemical Society
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• 제33권9호
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• pp.3125-3128
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• 2012

• 공업화학
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• 제10권5호
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• pp.804-807
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• 1999

페로센 카르복시알데히드와 1,2-diaminocyclohexane을 2:1로 반응시켜 키랄 리간드 L(L=N,N'-cyclohexane bis(ferrocenylmethylene)amine)을 합성하고 이를 구리와 반응시켜 새로운 구리 착물을 합성하였다. 이 착물들을 확인하고 비대칭 유기 합성반응에 촉매로 사용하였다. 구리(II) 착물들은 스티렌과 에틸디아조아세테이트와의 시클로프로판화 반응에서 촉매작용을 하지 않았으나 구리(I)화합물, Cu(I)LOTf (OTf=trifluoromethanesulfonate)는 시클로프로판 생성물 trans:cis의 비율에 있어 80:20 이상의 높은 regioselectivity를 보였다.

• Bulletin of the Korean Chemical Society
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• 제30권2호
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• pp.389-396
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• 2009

MFI structural zeolite (ZSM-5 or Sililcalite) was treated with HF solution to introduce mesoporous channels in the microporous crystals. Inner mesopore size could be controlled from 2.5 to 3.5 nm by changing the concentration of HF solution. The pore structure of HF-treated MFI zeolite was studied by instrumental analysis. The active Co (III) salen complex monomers were successfully anchored non-covalently on the surfaces of mesoporous MFI-type zeolite. These heterogeneous catalysts could be applied in asymmetric ring opening of terminal epoxides by phenol derivatives. It showed very high enantioselectivity and yield up to 95% in the catalytic synthesis of optically active $\alpha$-aryloxy alcohol compounds.