Abstract: A total synthesis of the marine natural product A9 ('2)-capnellene (6) is described. An intramolecular 1, 3-diyl trapping reaction constituted the cornerstone of the strategy that was utilized to achieve this objective. Unlike all previous intramolecular diyl trapping reactions that have been conducted, the major product was not a linearly fused tricyclopentanoid. Rather, ketone 16, possessing a tricyclo [5.3. 1. 02* 6] undecane ring ...
