Gold-Catalyzed Diastereoselective Cycloisomerization of Alkylidene-Cyclopropane-Bearing 1,6-Diynes

An unprecedented gold‐catalyzed diastereoselective cycloisomerization of 1,6‐diynes bearing an alkylidene cyclopropane moiety has been developed. This methodology enables rapid access to a variety of 1,2‐trimethylenenorbornanes, which are important building blocks in the preparations of abiotic and sesquiterpene core structures. When gold met alkylidenecyclopropane: Cationic gold catalysts can mediate the highly exothermic (≈60 kcal mol−1) cycloisomerization of 1,6‐diynes bearing an alkylidene cyclopropane moiety. This diastereoselective methodology efficiently generates 1,2‐trimethylenenorbornanes, an important building block for abiotic targets and sesquiterpene natural products. DCE=1,2‐dichloroethane, Tf=trifluoromethanesulfonyl, Tol=Tolyl.