Palladium-Catalyzed Double C–H Arylation Reaction: Tandem Synthesis of Benzo[a]imidazo[5,1,2-cd]indolizines from Imidazo[1,2-a]pyridines and o-Dihaloarenes

Abstract A palladium-catalyzed direct arylation of 2-arylimidazo[1,2-a]pyridines with o-dihaloarenes via double C–H activation is described. The process comprises intermolecular C3-arylation of 2-arylimidazo[1,2-a]pyridines followed by an intramolecular C5-arylation in a highly regioselective fashion, affording benzo[a]imidazo[5,1,2-cd]indolizine derivatives in moderate to good yields.