The resonance stabilization energies, E(s), of polyenyl radicals can b
e estimated by the equation E(s)(N)= -13.2 + [3.95-15.8(2)-(2/n) ] kca
l mol(-1), where N is the number of C, C-pi bonds in the polyenyl radi
cals. This correlation has been extended for predicting the weakest H-
C, C-C and C-OH bond dissociation energies in vitamin A and similar co
mpounds.