An Enantioselective Approach to Heteroatom-Containing Bicyclic Derivatives via Inverse-Electron-Demand Diels-Alder Reactions

Comprehensive Summary Chiral heteroatom-containing bicyclic scaffolds are important pharmacophores and prevalent in bioactive natural products and drug molecules. Herein, we report a unified approach for the divergent synthesis of chiral heteroatom-containing bicyclic derivatives by lanthanide (III)-catalyzed asymmetric inverse-electron-demand Diels-Alder reactions of 2-pyrones. These reactions occur with various readily available dihydropyrroles and dihydrofurans as dienophiles, providing a step-economical synthetic platform for densely functionalized cis-hydroindoles and cis-hydrobenzofurans with excellent yields and enantioselectivities. The synthetic utility of this approach is demonstrated by the concise synthesis of (-)-alpha-lycorane and (-)-lycorine alkaloids.