Gold‐Catalyzed Cyclopenta‐ and Cycloheptannulation Cascades: A Stereocontrolled Approach to the Scaffold of Frondosins A and B

Golden cascades: Two diastereoselective gold-catalyzed cascade processes in which propargyl acetates react with alkenes or 1,4-dienes afford highly substituted five- and seven-membered rings, respectively (see scheme). The concerted nature of the gold-catalyzed Cope rearrangement has been used in the formal enantioselective synthesis of marine norsesquiterpenoids Frondosins A and B.