Palladium‐Catalyzed Synthesis of Tetrasubstituted Olefins by Triple Domino Process

An efficient, highly regio‐ and stereoselective protocol for the synthesis of tetrasubstituted olefins was developed to take place by a palladium(0)‐catalyzed triple domino process. It involves the formation of three new C−C bonds through double carbopalladation and C−H activation across 2‐bromoaryl alkynyl biaryls/heteroaryls with norbornene. This method is practically simple with broad substrate scope and tolerates a wide range of substituents. The products bearing 9H‐pyrrolo[1,2‐a]indole motifs reveal intriguing solid state fluorescence properties and thus form a new class of aggregation induced emission (AIE) fluorophores.