1,4-Palladium Migration via C−H Activation, Followed by Arylation:  Synthesis of Fused Polycycles

A novel palladium migration/arylation methodology for the synthesis of complex fused polycycles has been developed, in which one or more sequential Pd-catalyzed intramolecular migration processes involving C−H activation are employed. The chemistry works best with electron-rich aromatics, which is in agreement with the idea that these palladium-catalyzed C−H activation reactions parallel electrophilic aromatic substitution.