Concise Formal Synthesis of the Pseudopterosins via Anionic Oxy-Cope/Transannular Michael Addition Cascade

An anionic oxy-Cope/transannular Michael addition cascade converts a spirocyclic architecture—readily available by Diels–Alder cycloaddition—into the hydrophenalene carbon skeleton of the pseudopterosin aglycones. Oxidation of the resulting cyclohexenone ring to the phenol that is characteristic of the targets completes a short formal synthesis.