A short, general protocol for the synthesis of linear triquinane natural products is delineated. The key element of this approach is the stepwise (photothermal) metathesis of Diels-Alder adducts derived from substituted 1,3-cyclopentadiene and p-benzoquinone. The methodology has been applied to the total synthesis of sesquiterpene hydrocarbons (±)-hirsutene 2, (i)-capnellene 3, and the antitumor compound, (±)-coriolin 5. Thus, 1,3-cyclopentadiene and 2,5-dimethyl-p-benzoquinone furnish the Cu-bisenone 12 bearing 13 of the 15 carbon atoms of hirsutene and coriolin in only three steps. A series of regioand chemoselective operations were performed on 12 to deliver 2 and 5 in 10 and 17 steps, respectively. Similarly, 1methylcyclopentadiene and p-benzoquinone were employed as synthons for two syntheses of marine natural product capnellene

Oxidative allylation to sp(2)- and sp(3)-carbon attached to the nitrogen atom was accomplished. The alpha-allylation of tertiary amines was catalyzed by easily available hydrated iron(III) chloride in combination with air or aqueous (t)BuOOH. Remarkably, N-allyl- and N-propagyl-tethered tertiary amines were also allylated through this protocol.

A simple synthesis of (A) -coriolin (4) from the readily available cis,anti,cis-tricyclic C,,-dione ( 5 ) is reported.

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