Toward the synthesis of phomoidride D.

An efficient and highly stereoselective approach toward the phomoidride family of natural products is described. The carbocyclic core structure was assembled using a tandem phenolic oxidation/Diels–Alder cycloaddition and a tandem 5-exo-trig/5-exo-trig radical cyclization to deliver an isotwistane intermediate that, upon a late-stage xanthate-initiated Grob fragmentation, furnishes the requisite bicyclo[4.3.1]decene.