Toward a Unified Approach for the Lycopodines: Synthesis of 10-Hydroxylycopodine, Deacetylpaniculine, and Paniculine

The enantioselective syntheses of 10-hydroxylycopodine, deacetylpaniculine, and paniculine have been accomplished through use of a common intermediate. Key steps in the synthetic sequence toward these lycopodium alkaloids include formation of the tricyclic core via a conformationally accelerated, intramolecular Mannich cyclization and an organocatalyzed, intramolecular Michael addition to form the C7–C12 linkage.