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Updated: Mar 31, 2026
Efficient Synthesis of All-Carbon Quaternary Centers via the Conjugate Addition of Functionalized Monoorganozinc Bromides
Published on: May 26, 2019
Rh-Catalyzed Desymmetrization of α-Quaternary Centers by Isomerization-Hydroacylation
Jung-Woo Park1, Kevin G M Kou1, Daniel K Kim1
1Department of Chemistry, University of California-Irvine, 4403 Natural Sciences 1, Irvine, California 92697, USA.
Abstract:
We describe a Rh-catalyzed desymmetrization of all-carbon quaternary centers from α,α-bis(allyl)aldehydes by a cascade featuring isomerization and hydroacylation. This desymmetrization competes with two other novel olefin functionalizations that are triggered by C-H bond activation, including carboacylation and bisacylation. A BIPHEP ligand promotes enantioselective formation of α-vinylcyclopentanones. Mechanistic studies support irreversible and enantioselective olefin-isomerization followed by olefin-hydroacylation.
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