Autoxidation of Polyunsaturated Fatty Acids, an Expanded Mechanistic Study

Article abstract of DOI:10.1021/ja00321a022

The autoxidation of four isomeric methyl 9,12-octadecadienoates in benzene/1,4-cyclohexadiene has been investigated.Autoxidation of the isomers 9-Z,12-Z (methyl linoleate); 9-Z,12-E;9-E,12-Z; and 9-E,12-E (methyl linoelaidate) octadecadienoates was studied.With no cyclohexadiene or with low cyclohexadiene solvent composition, the distribution of product hydroperoxides from the various isomeric precursors was equivalent or nearly so.With higher cyclohexadiene solvent composition, the product mixtures became nonequivalent and reflected the stereochemistry of the particular diene precursor.A steady-state and iterative computer kinetic analysis is reported, and a scheme for diene fatty acid autoxidation involving reversible oxygen addition to intermediate pentadienyl carbon radicals is proposed.