Skeletal diversity via a folding pathway: synthesis of indole alkaloid-like skeletons

Inspired by the skeletal diversity of naturally occurring indole alkaloids and the rich potential of chemistry developed by Padwa and co-workers, we conceived a pathway entailing six modes of intramolecular reactions leading to indole alkaloid-like skeletons. In this context, an efficient folding pathway via a rhodium-catalyzed tandem cyclization-cycloaddition involving three of the modes has been developed (two of which are shown above) that affords densely functionalized compounds with three distinct skeletons in a stereocontrolled manner.