Despite the possibility of intermolecular attack at four different locations, the Bu₃Sn-mediated radical cyclization of aromatic enynes is surprisingly selective. The observed reaction path originates from the least stable of the equilibrating pool of isomeric radicals produced by intermolecular Bu₃Sn attack at the π-bonds of substrates. The radical pool components are kinetically self-sorted via 5-exo-trig closure, the fastest of the four possible cyclizations. The resulting Sn-substituted indenes are capable of further transformations in reactions with electrophiles.