A catalytic amount of pTSA has been found to be effective to carry out a one-pot three-component coupling of aromatic aldehydes, enolizable ketones or ketoesters, and acetonitrile in the presence of acetyl chloride to afford β-acetamidoketones in high yields. Short reaction times and inexpensive catalyst are main advantages of this protocol.Key words: β-acetamidoketone, pTSA, multicomponent reaction, diastereoselectivity.