Catalytic Asymmetric Dihydroxylation of Olefins with Reusable OsO₄^2- on Ion-Exchangers:  The Scope and Reactivity Using Various Cooxidants

• Abstract
• Full Text HTML
• Hi-Res PDF[113 KB]
• PDF w/ Links[194 KB]

• Figures
• Citing Articles

Your current credentials do not allow retrieval of the full text.

Purchase the full-text

• PDF/HTML,
  figures/images,
  references and tables,
  (where available)

Abstract

Exchanger-OsO₄ catalysts are prepared by an ion-exchange technique using layered double hydroxides and quaternary ammonium salts covalently bound to resin and silica as ion-exchangers. The ion-exchangers with different characteristics and opposite ion selectivities are specially chosen to produce the best heterogeneous catalyst that can operate using the various cooxidants in the asymmetric dihydroxylation reaction. LDH-OsO₄ catalysts composed of different compositions are evaluated for the asymmetric dihydroxylation of trans-stilbene. Resin-OsO₄ and SiO₂-OsO₄ designed to overcome the problems associated with LDH-OsO₄ indeed show consistent activity and enantioselectivity in asymmetric dihydroxylation of olefins using K₃Fe(CN)₆ and molecular oxygen as cooxidants. Compared to the Kobayashi heterogeneous systems, resin-OsO₄ is a very efficient catalyst for the dihydroxylation of a wide variety of aromatic, aliphatic, acyclic, cyclic, mono-, di-, and trisubstituted olefins to afford chiral vicinal diols with high yields and enantioselectivities irrespective of the cooxidant used. Resin-OsO₄ is recovered quantitatively by a simple filtration and reused for a number of cycles with consistent activity. The high binding ability of the heterogeneous osmium catalyst enables the use of an equimolar ratio of ligand to osmium to give excellent enantioselectives in asymmetric dihydroxylation in contrast to the homogeneous osmium system in which excess molar quantities of the expensive chiral ligand to osmium are invariably used. The complexation of the chiral ligand (DHQD)₂PHAL, having very large dimension, a prerequisite to obtain higher ee, is possible only with the OsO₄^2- located on the surface of the supports.

Citing Articles

View all 81 citing articles

Citation data is made available by participants in CrossRef's Cited-by Linking service. For a more comprehensive list of citations to this article, users are encouraged to perform a search in SciFinder.

This article has been cited by 14 ACS Journal articles (5 most recent appear below).

• 

  Silylation of Layered Double Hydroxides via a Calcination−Rehydration Route

  Qi Tao, Jianxi Zhu, Ray L. Frost, Thor E. Bostrom, R. Mark Wellard, Jingming Wei, Peng Yuan and Hongping He
  Langmuir2010 26 (4), 2769-2773

  • Silylation of Layered Double Hydroxides via a Calcination−Rehydration Route

    Qi Tao, Jianxi Zhu, Ray L. Frost, Thor E. Bostrom, R. Mark Wellard, Jingming Wei, Peng Yuan and Hongping He
    Langmuir2010 26 (4), 2769-2773

    Silylated layered double hydroxides (LDHs) were synthesized through a surfactant-free method involving an in situ condensation of silane with the surface hydroxyl group of LDHs during its reconstruction in carbonate solution. X-ray diffraction (XRD) ...

    Abstract | Full Text HTML | Hi-Res PDF | PDF w/ Links
• 

  Noncovalent Immobilization of Enantioselective Catalysts

  José M. Fraile, José I. García and José A. Mayoral
  Chemical Reviews2009 109 (2), 360-417

  • Noncovalent Immobilization of Enantioselective Catalysts

    José M. Fraile, José I. García and José A. Mayoral
    Chemical Reviews2009 109 (2), 360-417
    Abstract | Full Text HTML | Hi-Res PDF | PDF w/ Links
• 

  Ion Exchange Resins: Catalyst Recovery and Recycle

  Pierluigi Barbaro and Francesca Liguori
  Chemical Reviews2009 109 (2), 515-529

  • Ion Exchange Resins: Catalyst Recovery and Recycle

    Pierluigi Barbaro and Francesca Liguori
    Chemical Reviews2009 109 (2), 515-529
    Abstract | Full Text HTML | Hi-Res PDF | PDF w/ Links
• 

  Organometallic Clusters As Precursors for Metallic Nanoparticles: Effect of Cluster Size, Ligand Set, and Decomposition Method

  Chunxiang Li, Ziyi Zhong and Weng Kee Leong
  Langmuir2008 24 (18), 10427-10431

  • Organometallic Clusters As Precursors for Metallic Nanoparticles: Effect of Cluster Size, Ligand Set, and Decomposition Method

    Chunxiang Li, Ziyi Zhong and Weng Kee Leong
    Langmuir2008 24 (18), 10427-10431

    The pyrolysis of organometallic clusters containing osmium and/or ruthenium on a silica support leads to metallic nanoparticles in the 1 to 10 nm size range. The particle size obtained is correlated to the ligand set, and there are also indications that ...

    Abstract | Full Text HTML | Hi-Res PDF | PDF w/ Links
• 

  Improved Procedure for the Synthesis of Enamine N-Oxides

  David Bernier, Alexander J. Blake and Simon Woodward
  The Journal of Organic Chemistry2008 73 (11), 4229-4232

  • Improved Procedure for the Synthesis of Enamine N-Oxides

    David Bernier, Alexander J. Blake and Simon Woodward
    The Journal of Organic Chemistry2008 73 (11), 4229-4232

    An improved procedure for the preparation of enamine N-oxides involving aminolysis of epoxides, chlorination, N-oxidation, and dehydrochlorination is described. Although isolated β-chloroamine N-oxides are prone to rearrangements when isolated, these ...

    Abstract | Full Text HTML | Hi-Res PDF | PDF w/ Links

SciFinder Links

• Get Reference Detail
• Get Substances
• Get Reactions
• Get Cited
• Get Citing