1 / 17

Relay Ring Closing Metathesis

Relay Ring Closing Metathesis. Variations on a Theme. RCM Powerful and widely used method Limitations Sterically hindered alkenes Electronically deactivated alkenes. RRCM Substrate designed to dictate the sequence of metathesis events through the individual steps of the RCM

peers
Download Presentation

Relay Ring Closing Metathesis

An Image/Link below is provided (as is) to download presentation Download Policy: Content on the Website is provided to you AS IS for your information and personal use and may not be sold / licensed / shared on other websites without getting consent from its author. Content is provided to you AS IS for your information and personal use only. Download presentation by click this link. While downloading, if for some reason you are not able to download a presentation, the publisher may have deleted the file from their server. During download, if you can't get a presentation, the file might be deleted by the publisher.

E N D

Presentation Transcript

  1. Relay Ring Closing Metathesis Variations on a Theme

  2. RCM Powerful and widely used method Limitations Sterically hindered alkenes Electronically deactivated alkenes RRCM Substrate designed to dictate the sequence of metathesis events through the individual steps of the RCM Substrate controlled reaction Intramolecular loading of Ru catalyst RRCM (Relay Ring Closing Metathesis)

  3. Increasing Reactivity By RRCM E=CO2Et Hoye et al JACS2004, 126, 10210

  4. Bidirectional RRCM • Demonstrates cyclization • Onto an electron deficient alkene [ 6 to 7 ] • Into an electron deficient alkene [ 8 to 7 ]

  5. RRCM Choreography with G2 with G1

  6. Non Obvious Advantage • Remote atom and all it bears is expendable during RRCM. • Hoye used larger groups near the alcohol to increase resolution.

  7. Retrosynthetic Analysis of Oximidine III Porco Angew. Int. Ed. 2004,43, 3601

  8. Metathesis Strategy

  9. Enyne Synthesis Hansen, E.P.; Lee,D. Org. Lett.2004, 6, 2035

  10. Cross Metathesis of Conjugated Enynes

  11. Cross Metathesis of Conjugated Enynes

  12. Mechanism of CM without Relay

  13. Cross Metathesis

  14. Cross Metathesis of Conjugated Enynes

  15. CM Metathesis with Relay

More Related