Synthesis of Bridged Bicyclic Systems peri‐Annulated to the Indole Ring: Tropane‐Fused Indoles

Abstract Ytterbium triflate catalysed domino reaction of (3‐formyl‐4‐indolyl)‐derived donor‐acceptor cyclopropane with primary amines provides a simple approach to an unprecedented tetracyclic skeleton in which tropane system is peri ‐annulated with an indole core. This process involves the formation of an imine and its (3+2)‐cross‐cycloaddition with donor‐acceptor cyclopropane moiety, yielding tropane‐fused indole core under mild reaction conditions. These products are of significant interest for pharmacology as potential hybrid molecules with a dual mode of action.