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Reusable Ru and Rh catalysts for ester hydrogenations and enyne cycloisomerizations

  • Author / Creator
    Hass, Michael J.
  • A method was developed to immobilize and reuse a catalyst for the asymmetric cycloisomerization of enynes. Immobilization is achieved through use of metal containing monomers, which are reacted with a cycloolefin via an alternating ring-opening metathesis polymerization, assembling a three-dimensional catalyst-organic framework. For example, [RhCl((R)-5,5'-dinorimido BINAP)]2 was copolymerized with ciscyclooctene using trans-RuCl2(CHPh)(PCy3)2 as a catalyst. After supporting the resulting framework on barium sulphate, silver(I) hexafluoroantimonate was added in the presence of enyne substrates to generate cationic rhodium(I) sites. These catalytic rhodium(I) sites catalyzed the asymmetric cycloisomerization of enynes, and afforded a maximum of 620 turnovers and >99% ee over the course of six runs. This catalyst was also used for batch reactions with turnovers as high as 800. The maximum number of turnovers reported in literature for a homogeneous non-tandem cycloisomerization reaction is ten.

  • Subjects / Keywords
  • Graduation date
    2011-06
  • Type of Item
    Thesis
  • Degree
    Master of Science
  • DOI
    https://doi.org/10.7939/R3SP7J
  • License
    This thesis is made available by the University of Alberta Libraries with permission of the copyright owner solely for non-commercial purposes. This thesis, or any portion thereof, may not otherwise be copied or reproduced without the written consent of the copyright owner, except to the extent permitted by Canadian copyright law.
  • Language
    English
  • Institution
    University of Alberta
  • Degree level
    Master's
  • Department
    • Department of Chemistry
  • Supervisor / co-supervisor and their department(s)
    • Bergens, Steven H. (Chemistry)
  • Examining committee members and their departments
    • Buriak, Jillian M. (Chemistry)
    • Bergens, Steven H. (Chemistry)
    • Semagina, Natalia (Chemical and Materials Engineering)