The reaction of (1-methoxycarbonylpentadienyl)iron(1+) cations 1 with alkenyl Grignard reagents affords (2-alkenylpentenediyl)iron(1+) complexes 2. The reactivity of these complexes will be presented, including epoxidation, Heck reactions, olefin cross-metathesis, and cycloadditions. The organic ligand present in functionalized complexes 2 can be liberated under oxidative conditions to afford divinylcyclopropanes. Cope rearrangement of the divinylcyclopropanes gives cycloheptadienes.