Reaction of Maleic Anhydride with cis‐Isolated Unsaturated Fatty Acid Esters

Abstract

Abstract The structures of maleic anhydride adducts of essentially pure oleic, linoleic and linolenic methyl esters have been determined. The cleavage of the methyl oleate adduct yields a product with a succinyl structure, with or without shift of the double bond; four isomeric structures are possible. The first adduct of maleic anhydride with methyl linoleate is a succinyl derivative followed by a shift into the conjugated isomer with which the second maleic anhydride reacts via a 1–4 Diels Alder addition to yield a second adduct having a cyclohexene structure. The first two moles of maleic anhydride add to methyl linolenate to form di‐succinyl derivatives followed by a shift into conjugated diene and triene. The third maleic anhydride adds via a 1–4 addition to yield a disuccinyl and one 1–4 adduct. A number of isomers are possible for the linoleate and linolenate adduct.