Studies on the autoxidation of nonbranched aliphatic monocarboxylic acids and their methyl esters

Valeric, caproic, and heptanoic acid and their methyl esters were oxidized at 140°C by molecular oxygen. The oxidation mixtures were reduced by LiAlH₄ and the mono- and dihydroxy compounds formed were analyzed gaschromatographically. From the results obtained one can conclude that nonbranched aliphatic acids and their methyl esters are attacked by the chain-carrying peroxy radicals at the different C H bonds with almost the same regioselectivity as normal paraffins Only the ß- and to a smaller extent the α-positions are desactivated by the neighbouring carboxylic group.