Synthesis of 6-Substituted 3-(Alkoxycarbonyl)-5-aryl-α-pyrones.

An efficient synthesis of 6-substituted 3-(alkoxycarbonyl)-5-aryl-α-pyrones is reported. This methodology consists of the successive manipulation of an addition–elimination reaction between benzyl ketone derivatives and dimethyl methoxymethylenemalonate, and an acid-catalyzed condensation reaction. The synthesis is applicable to various 5- p -substituted-aryl 6-substituted α-pyrones and good to excellent yields were obtained over two steps from benzyl ketone derivatives that were easily prepared from phenylacetic acid by the Negishi coupling or the Claisen decarboxylation reaction.