Metathesis and Decomposition of Fischer Carbenes of Cyclometalated Z-Selective Ruthenium Metathesis Catalysts
The addition of vinyl ethers to Z-selective, cyclometalated ruthenium metathesis catalysts generates Fischer carbene complexes. Although Fischer carbenes are usually thought to be metathesis inactive, we show that Fischer carbenes are metathesis active under certain circumstances. These species were found to decompose facilely to Ru hydride complexes, as identified by both experiment and computation. Since vinyl ethers are often used to quench metathesis reactions implementing Ru-based metathesis catalysts, their decomposition to hydrides can have a deleterious effect on the desired stereochemistry of the olefin product.
© 2018 American Chemical Society. Received: March 10, 2018; Published: July 10, 2018. The research described was financially supported by the NSF (CHE-1502616), NIH (GM031332), and ONR (N000141310895 and N00014-14-1-0650). Calculations were performed using the NSF funded (OCI-1053575) Extreme Science and Engineering Discovery Environment (XSEDE), the UCLA IDRE Hoffman2 Cluster, and the ONR supported Copper Cluster. T.S.A. is grateful for support from the National Science Foundation through a Graduate Research Fellowship. D. VanderVelde is acknowledged for his assistance with NMR experiments. B. L. Quigley is thanked for helpful discussions. Materia, Inc. is thanked for generous donations of catalysts 3 and 4. Author Contributions: T.S.A. and J.M.G. contributed equally to this work. Ahmed performed the majority of experiments and Grandner performed all computations. The authors declare no competing financial interest.
Published - acs.organomet.8b00150.pdf
Supplemental Material - om8b00150_si_001.pdf
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