Palladium-Catalyzed Intramolecular Diarylation of 1,3-Diketone in Total Synthesis of (±)-Spiroaxillarone A.

A sterically congested all-carbon quaternary center was installed for the first time via a Pd-catalyzed cascade diarylation with aryl bromides and acyclic 1,3-diketones. This method was used as a key step in the total synthesis of (±)-spiroaxillarone A. Computational experimental results indicated that the selective diarylation is accelerated by the higher free-energy barriers of the endothermic transmetalation and reductive elimination in the first arylation step.