Aktmct: Thermochemical studies of perpendicular alkene triplets demonstrate that their energies are almost exactly those expected from Benson estimations using group equivalents for appropriate free radicals as models for the termini (the two essential carbons of the alkene triplet). If these species are to he described as 1, 2-hiradicals, their reactivities in reactions for which the termini act indepcndently should he similar to corresponding ...