• 제목/요약/키워드: Asymmetric Catalyst

검색결과 54건 처리시간 0.021초

배기 매니폴드 확관부 형상 최적화에 관하여 (About the Shape Optimization of Ex-Manifold Diffuser)

  • 조석현
    • 대한기계학회논문집B
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    • 제28권9호
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    • pp.1133-1138
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    • 2004

  • Shape optimization method was coupled with a conventional CFD analysis to find the optimal shape of ex-manifold diffuser which decreases the maldistribution of flow above the catalyst. Shape optimization results show that flow uniformity above the catalyst was increased about 28% fur the axi-symmetric case and about 18% for the asymmetric case. The axi-symmetric type can be applied to the diffuser of under floor catalyst and the asymmetric type can be applied to the diffuser of close coupled catalyst.

  • https://doi.org/10.3795/KSME-B.2004.28.9.1133 인용 PDF KSCI

Asymmetric Michael Addition of Ketones to Nitroolefins Catalyzed by a New Chiral Catalyst

  • Wang, Lian-Jun;Hu, Feng-Feng
    • Bulletin of the Korean Chemical Society
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    • 제31권5호
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    • pp.1280-1282
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    • 2010

  • A new chiral catalyst was synthesized and found that it could catalyzed the asymmetric Michael reaction of ketones with nitroolefins smoothly at room temperature, giving the desired adducts in 71 - 92% yields with excellent diastereoselectivities and high enantioselectivities (up to 95% ee).

  • https://doi.org/10.5012/bkcs.2010.31.5.1280 인용 PDF KSCI

A New Approch for Catalyst Optimization: Host/Guest Complexes of Chiral Bisphosphine Bearing Imidazolidinone and Their Application in Rh-Catalyzed Asymmetric Hydrogenation

  • Park, Jung-Hwan;Shin, Hyun-Ik;Park, Doo-Han;Lee, Sang-Gi
    • Bulletin of the Korean Chemical Society
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    • 제31권3호
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    • pp.635-638
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    • 2010

  • As a new strategy for the optimization of a chiral catalyst, the catalytic activity of the host-guest complexes of chiral bisphosphine bearing imidazolidinone was investigated in Rh-catalyzed asymmetric hydrogenation of enamide. Marginal enhancement in enantioselectivity was observed and the nature of interaction between host-guest was experimentally elucidated.

  • https://doi.org/10.5012/bkcs.2010.31.03.635 인용 PDF KSCI

새로운 술폰아미드계의 촉매의 합성 (Synthesis of Indoline tri-isopropyl benzene sulfonamide as a potential new asymmetric catalyst)

  • 윤인권;김환철
    • 자연과학논문집
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    • 제7권
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    • pp.47-51
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    • 1995

  • 입체 이성질체를 합성하는 방법으로 최근에 알려진 입체선택성 촉매를 이용한 유기반응을 연구 하기 위하여 비천연 아미노산인 인돌린-2- 카르본산으로 부터카르본산그룹의 환원,2차아민기의 보호화,메실화,아지도치환,환원에 의한 아민기로의 전환, 술폰화, 보호기제거등의 총 5단계의 합성과정을 거쳐 목적하는 술폰아미드를 합성하였다. 각 생성물은 관 크로마토그래피에 의하여 분리 정제후 핵자기공명스펙트럼($^1H,^13C $ NMR) 적외선 스펙트럼 등에 의하여 구조를 확인 하였다.

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Synthesis of New Bimetallic Chiral Salen Catalyst Bearing Co(BF4)2 Salt and Its Application in Asymmetric Ring Opening of Epoxide

  • Kim, Yong-Suk;Lee, Choong-Young;Kim, Geon-Joong
    • Bulletin of the Korean Chemical Society
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    • 제31권10호
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    • pp.2973-2979
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    • 2010

  • The newly synthesized homogeneous chiral Co(III) salen complexes were anchored non-covalently on the acidic sites of mesoporous Al-SBA-15. The Bronsted and Lewis acidic sites are attributed to the immobilization of fluorine functionalized chiral salen complexes on the supports. XRD, BET, TEM, FT-IR and ESCA (XPS) analyses were performed to characterize the property of support, and the structure of new homogeneous and heterogeneous chiral Co salen catalyst. The homogeneous and heterogeneous catalysts could be applied in asymmetric ring opening of epichlorohydrine (ECH) by water. They showed very high enantioselectivity and a good yield up to 99% in the catalytic synthesis of optically active products.

  • https://doi.org/10.5012/bkcs.2010.31.10.2973 인용 PDF KSCI