• Title/Summary/Keyword: Alkene epoxidation

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Epoxidation of Simple Alkenes with O2 and Isobutyraldehyde Catalyzed by Ni Catalysts Deposited on Nanoporous Carbon

  • Lim, So-Young;Kang, Min;Kim, Ji-Man;Lee, Ik-Mo
    • Bulletin of the Korean Chemical Society
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    • v.26 no.6
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    • pp.887-891
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    • 2005
  • Novel nickel catalyst deposited on nanoporous carbon was found to be an efficient catalyst for the epoxidation of simple alkenes with $O_2$ and isobutyraldehyde under mild conditions. Alkenes exhibited different reactivities towards Ni-catalyst and epoxidation with stilbene proceeds stereospecifically. This may be rationalized with the mechanism involving coordinated acylperoxy radical intermediate. Nickel contents depend on the preparative methods and the KNI-3 catalyst, which was synthesized by wet impregnation of $Ni(NO_3)_2$ into nanoporous carbon, shows the highest activity. The activity of the catalyst is well correlated with contents of nickel. Recycled catalysts suffer considerable loss of activity due to leaching of catalytic active species, nickel.

Biocatalysis and Biotransformation for the Production of Chiral Epoxides (바이오촉매 및 생물전환을 이용한 광학활성 에폭사이드 제조)

  • Kim, Hee-Sook;Lee, Ok-Kyung;Lee, Eun-Yeol
    • Journal of Life Science
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    • v.15 no.5 s.72
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    • pp.772-778
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    • 2005
  • Chiral epoxides are important chiral synthons in organic synthesis for the production of chiral pharmaceuticals and functional food additives. Chiral epoxides can be synthesized by enantioselective introduction of oxygen to double bond of substrate by monooxygenase. Peroxidase also carry out asymmetric epoxidation of alkene in the presence of hydrogen peroxide. Kinetic resolution of racemic epoxides via enantioselective hydrolysis reaction by epoxide hydrolase (EH) is a very promising method since chiral epoxides with a high optical purity can be obtained from cheap and readily available racemic epoxides. In this review, various biocatalytic approaches for the production of chiral epoxides with several examples are presented and their commercial potential is discussed.