Oxidation of Lipids. IX. Decomposition of Methyl Linoleate and Methyl Linolenate Hydroperoxides in Solution

Decompositions of methyl linoleate hydroperoxide (LOOH) induced by di-t-butyl diperoxyoxalate and cobalt ions were investigated in benzene at 50 °C under vacuum to elucidate the degradation mechanism. The major products were dimer (LOOL), oxodiene, hydroxydiene and epoxyhydroxyene (and/or epoxyoxoene). It was suggested that these products were formed by the recombination of L· and LOO· radicals, β-scission of LO· radical, hydrogen abstraction of LO· radical, and intramolecular epoxidation of LOO· radical, respectively. The decomposition of methyl linolenate hydroperoxide (L′OOH) was also studied. The major products were dimer, oxotriene, hydroxytriene, and thiobarbituric acid reactive substances, which were suggested to be formed by the intramolecular cyclization of L′OO· radical.