Remote Stereocontrol of All-Carbon Quaternary Centers via Cobalt-Catalyzed Asymmetric Olefin Isomerization

Asymmetric olefin isomerization has become a powerful tool for positional migration of C=C double bonds to afford valuable chiral olefins. However, the synthesis of optically active all-carbon quaternary stereocenters via this strategy is still rare. Herein, we report a cobalt-catalyzed desymmetric olefin isomerization to access 1-methylcyclohexenes bearing beta-quaternary stereocenters in a chemo-, site-, and stereoselective fashion. Preliminary mechanistic studies have revealed the Co-H insertion/beta-Helimination reaction pathway and the origin of remote stereocontrol of all-carbon quaternary centers. The gram-scale synthesis and stereoretentive transformations of spirocyclic products demonstrate the synthetic utility of this reaction. [GRAPHICS] .