Pivalic acid

Pivalic acid is a carboxylic acid with a molecular formula of (CH3)3CCO2H. This colourless, odoriferous organic compound is solid at room temperature. Two abbreviations for pivalic acid are t-BuC(O)OH and PivOH. The pivalyl or pivaloyl group is abbreviated t-BuC(O). Salts of the acid is called pivalates. Pivalic acid is an isomer of valeric acid, the other two isomers of it are 2-methylbutanoic acid and 3-methylbutanoic acid. Pivalic acid is prepared on a commercial scale by hydrocarboxylation of isobutene via the Koch reaction: Such reactions require an acid catalyst such as hydrogen fluoride. tert-Butyl alcohol and isobutyl alcohol can also be used in place of isobutene. Globally, several million kilograms are produced annually. Pivalic acid is also economically recovered as a byproduct from the production of semisynthetic penicillins like ampicillin and amoxycillin. It was originally prepared by the oxidation of pinacolone with chromic acid.