Studies toward the Syntheses of Functionally Substituted γ-Butyrolactones and Spiro-γ-butyrolactones and Their Reaction with Strong Acids: A Novel Route to α-Pyrones

Article abstract of DOI:10.1021/jo00271a023

A general strategy for the conversion of 5-keto carboxylic acids, 6 (via their enol-lactones 7), to a variety of γ-lactones, 8a-c, and spiro-γ-lactones, 8d-g, is described.Lactones 8b and 8d,e may be further converted into the corresponding α-pyrones, 17b and 17d,e, respectively, in the presence of strong acids.