Enantioselective Access to Lactam-Fused Eight-Membered Bridged Biaryls via N-Heterocyclic Carbene-Catalyzed [5 + 3]-Domino Annulation

We disclose herein an efficient asymmetric synthesis of axially chiral lactam-fused bridged biaryls through an N-heterocyclic carbene-catalyzed [5 + 3] annulation of ortho-indolizinyl N-sulfonylanilines with α-bromoenals. This transformation proceeds via a Michael/lactamization domino sequence under mild conditions, enabling facile access to a diverse array of valuable medium-sized bridged heterobiaryls in good to high yields with excellent enantiocontrol. The scalability and facile derivatization of the enantioenriched products underscore the synthetic utility of this method.