Fatty acids,part 54. Some reactions of long-chain oxygenated acids with special reference to those furnishing furanoid acids

C₁₈ furanoid acids are prepared from natural oxygenated acids by palladium (II)-catalysed cyclodehydrogenation, by rearrangement of epoxides with iodopropane-sodium iodide-dimethylsulphoxide, and by dehydration of endoperoxides. Some reactions give mixed products but routes to the individual 10,13-, 9,12- and 8,11-furans are reported. The endoperoxide route leads to speculation about the biosynthesis of natural furanoid acids.