AbstractThe nonthermal structural rearrangements of cyclooctatetraene to semibullvalene and 2,3‐dihydrotriquinacen‐2‐one are described. The first pathway, which is entirely general in its scope, entails as its key step the Ag(I)‐catalyzed 1,8‐bishomocubane → snoutane isomerization reaction. Subsequent hydrolysis‐oxidation provides 9,10‐diazasnoutenes, which cannot be isolated but lose nitrogen rapidly with generation of the semibullvalenes. The equilibrium imbalances that arise upon monosubstitution and 2,8‐annulation of this divinylcyclopropane system are also outlined. Cycloaddition of TCNE to cyclooctatetraeneiron tricarbonyl affords an unusual α,π‐Fe(CO)3 complex, oxidative decomposition of which gives 2,2,3,3‐tetracyanodihydrotriquinacene. A four‐step conversion of the latter to triquinacene‐2‐carboxylic acid is outlined. Resolution of the acid and conversion of the chiral material to (+)‐2,3‐dihydrotriquinacen‐2‐one serves as a prelude to dimerization of these “halves” to potential dodecahedrane precursors. The thermally promoted degenerate isomerization and rearrangement reactions of a variety of cyclooctatetraenes are next presented. Lastly, the latent potential of the [8]annulene ring system to function as a neighboring group in carbonium ion processes is discussed.