2,5-Bis(4-methylphenyl)-4-oxopentanoic acid

The title compound, C19H20O3, was obtained from 1,4-bis(4-methylphenyl)but-3-yn-2-one in the presence of carbon monoxide by Ni(CN)2 catalysis in a basic aqueous medium. Intermolecular O—H...O hydrogen bonds lead to the formation of hydrogen-bonded carboxylic acid dimers [graph-set motif R22(8)]. Weak C—H...O hydrogen bonds between neighbouring dimers further extend the structure to give rise to a three-dimensional supramolecular network.