Surface active N‐acylglutamate: I. Preparation of long chain N‐acylglutamic acid

Abstract Long chain N‐acylglutamic acid was prepared in a high yield by a reaction of glutamic acid with fatty acid chloride in a mixed solvent of water and a water miscible organic solvent such as acetone, methyl ethyl ketone, dioxane, tetrahydrofuran, t ‐butyl alcohol or cyclohexanone. In this reaction the composition of the mixed solvent influenced the yield of N‐acylated glutamic acid and the best yield was obtained when the reaction was carried out in the mixed solvent comprising 30–60% v/v of the organic solvent. Long chain N‐acylaspartic acid was also obtained in a high yield by the same method. As the other method to obtain N‐lauroyl‐ D L ‐glutamic acid, it was examined that N‐acyl‐α‐aminoglutarodinitrile which was obtained by a reaction of α‐aminoglutarodinitrile with fatty acid chloride was hydrolyzed with an aqueous alkaline solution. The salts of long chain N‐acylglutamic acid are known as the surface active agents that react mildly on the human skin.