Enantioselective Formation of Quaternary Centers by Allylic Alkylation with First-Row Transition-Metal Catalysts
Asymmetric allylic alkylation mediated by transition metals provides an efficient strategy to form quaternary stereogenic centers. While this transformation is dominated by the use of second- and third-row transition metals (e.g., Pd, Rh, and Ir), recent developments have revealed the potential of first-row transition metals, which provide not only a less expensive and potentially equally efficient alternative but also new mechanistic possibilities. This review summarizes examples for the assembly of quaternary stereocenters using prochiral allylic substrates and hard, achiral nucleophiles in the presence of copper complexes and highlights the complementary approaches with soft, prochiral nucleophiles catalyzed by chiral cobalt and nickel complexes.
Additional Information© 2021 American Chemical Society. Received: October 13, 2020; Published: February 11, 2021. We thank NIH-NIGMS (R01GM080269) and Caltech for financial support. L.S. gratefully acknowledges the Alexander von Humboldt Foundation for a postdoctoral fellowship (2020). Author Contributions: The manuscript was written through contributions of all authors. The authors declare no competing financial interest.
Accepted Version - nihms-1746780.pdf