The total syntheses of penicibilaenes A and B are described. The key step is the t BuOK/DMSO-mediated tandem 5- exo - dig Conia-ene type reaction and 6- exo - dig Conia-ene type reaction to install the tricyclic [6.3.1.0 1,5 ] dodecane core of penicibilaenes from dibutynyl cyclohexanone in a single step, together with a sequence of copper-mediated conjugate addition and Crabtree's hydrogenation to forge the stereogenic centers at C5 and C2, respectively.
Keyphrases