Gold(I)-Catalyzed Synthesis of Indenes and Cyclopentadienes: Access to (±)-Laurokamurene B and the Skeletons of Cycloaurenones and Dysiherbols

The formal (3 + 2) cycloaddition between terminal allenes with aryl or styryl gold(I) carbenes generated by retro-Buchner reaction of 7-substituted 1,3,5-cycloheptatrienes leads to indenes and cyclopentadienes, respectively. These cycloadditions have been applied to the construction of the carbon skeleton of the cycloaurenones and the dysiherbols as well as to the total synthesis of ()-laurokamurene B.