A main‐group catalysis‐based strategy to access 8‐membered carbocycles via the direct carbofunctionalization of 2‐phenethyl‐substituted 1,3‐dienes is disclosed. Through the intervention of an I(I)/I(III) catalysis cycle, the synthesis of densely functionalized, fluorinated benzocyclooctenes can be achieved in an operationally simple manner. Modulating the oxidation/activation regime, and the external nucleophile, the process has been extended to unify the challenging cyclization with formation of allylic C−O, C−N, and C−C bonds (>30 examples). Derivatization of the product benzocyclooctenes is demonstrated together with X‐ray conformational analysis, preliminary validation of enantioselective catalysis and a scalable resolution protocol.