Abstract
cis-9, 10-Epoxyoctadecanoic acid was hydrolyzed with a diluted sulfuric acid in the presence of a small amount of a surface-active sulfonic acid [5, 8-diisopropyl-2-naphthalenesulfonic acid (HDNS)], and it was found that a considerably large amount of mono-HDNS esters of threo-9, 10-dihydroxyoctadecanoic acid were produced, besides threo-9, 10-dihydroxyoctadecanoic acid, well-known usually as a main reaction product in such acidic hydrolysis. Since HDNS was difficultly soluble in toluene, used as an oil phase in this reaction, under the reaction conditions, and moreover, threo-9, 10-dihydroxyoctadecanoic acid was found as a major reaction product of the similar reaction, carried out in a homogeneous reaction system applying dioxane as a solvent, it was considered that HDNS, used in the heterogeneous reaction, oriented and was locally concentrated on the oil-water interface, and consequently the monosulfonic acid esters of threo-9, 10-dihydroxyoctadecanoic acid, usually obtained in homogeneous reactions carried out in anhydrous organic solvents, were readily produced.
