Undecanoic acid

Undecanoic acid is a saturated fatty acid with the molecular formula: C11H22O2. The monocarboxylic acid is nearly insoluble in water, but soluble in organic solvents. Undecanoic acid has a melting point of 29 °C, so at room temperature it is a (white) solid. Undecanoic acid is found in some vegetable essential oils.

Synthetically, the acid can be produced by hydrogenation from the monounsaturated undecylenic acid. The methyl and ethyl esters are used in perfumery.

Undecanoic acid is used in cosmetic formulations under the INCI designation"Undecanoic acid". It acts as emulsifier (changes the interfacial tension of liquids like water and oil so that they can be mixed together) and skin cleansing agent (cleans the body surface). Furthermore, the acid has an antiseborrhoeic effect (helps to inhibit sebum production).