3methylbutanoic

3-methylbutanoic acid, also known as isovaleric acid or isopentanoic acid, is a carboxylic acid with the formula C5H10O2. It is the branched isomer of pentanoic acid and has the structure CH3-CH(CH3)-CH2-CO2H. The IUPAC name is 3-methylbutanoic acid.

Physically, isovaleric acid is a colorless liquid at room temperature and is notable for a characteristic pungent, sweaty odor. It is soluble in organic solvents and moderately soluble in water. The acid has a typical carboxylic acid functionality, with a pKa around 4.8, reflecting its acidity in aqueous solution.

Biosynthesis and occurrence: isovaleric acid is produced in biological systems as a metabolite of leucine catabolism and can appear in human sweat and sebum, contributing to odor. It also occurs in certain foods and fermentation products, including aged cheeses and some flavors and fragrances. In flavor science, it is valued both for its distinctive aroma and as a precursor to various esters used to shape fragrance and taste profiles.

Applications and synthesis: commercially it can be prepared by oxidation of the corresponding alcohol or aldehyde derivatives derived from 3-methyl-1-butanol (isopentyl alcohol). In industry, it serves as a chemical intermediate for esters and other derivatives used in perfumery and flavoring.

Safety: isovaleric acid is an irritant and should be handled with appropriate protective equipment. It is flammable and should be stored away from oxidizers and heat sources.