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Diastereoselective Construction of All-Carbon Quaternary Stereocenters via Intramolecular Oxidative Cross-Coupling Reaction

The formation of sterically hindered C — C bond represents a great challenge in modern synthetic organic chemistry. A particularly challenging issue is the construction of all-carbon quaternary stereocenters. Herein, a ceric ammonium nitrate (CAN)-mediated intramolecular oxidative cross-coupling of silyl ethers for direct construction of valuable polycyclic scaffolds is described. The reaction enables sterically congested vicinal all-carbon quaternary and tertiary stereocenters to be installed diastereoselectively. The developed method provides a concise and efficient approach for ligation of two different segments through a compact C — C bond formation, which has potential applications in the synthesis of com-plex molecules as well as sterically congested natural products.