On the Gold‐Catalyzed Generation of Phenyl Cations from 1,5‐Diynes

cis ‐Enediyne systems bearing two non‐terminal alkyne functionalities were transformed in the presence of a gold catalyst. A selective 6‐ endo ‐ dig ‐cyclization generates mono‐aurated phenyl cation intermediates, high energy species that are able to activate even primary sp 3 ‐C–H‐bonds. Via insertion into intramolecularly offered, unactivated C–H‐bonds, penta‐substituted benzene derivatives are obtained as final products. In most cases selective insertions into the γ‐ sp 3 ‐C—H bonds of the offered tethers were observed.