Gold‐Catalyzed Cascade Cyclizations of 1,6‐Diynyl Carbonates to Benzo[<i>b</i>]fluorenes Involving Arylation of Oxocarbenium Ion Intermediates and Decarboxylative Etherification

Abstract

Rearranged: The described gold-catalyzed cycloisomerizations give access to highly substituted benzo[b]fluorenes under mild reaction conditions (see scheme). Experimental results indicate that the in situ formed oxocarbenium ion intermediates, derived from gold-catalyzed 3,3-rearrangement and 6-endo-dig cyclization, undergo intramolecular arylation and subsequent decarboxylative etherification to furnish the final ether products.