The oxidation of non-phenolic alkanoic acid derivatives to oxygen heterocycles was investigated; a new oxidative route to dienone lactones has been developed using a combination of hypervalent iodine (III) reagent, phenyliodine (III) bis (trifluoroacetate)(PIFA), and heteropoly acid (HPA).
[Taylor, Edward C.; Andrade, Juan G.; Rall, Gerhardus J. H.; Turchi, Ignatius J.; Steliou, Kosta; et al. Journal of the American Chemical Society, 1981 , vol. 103, # 23 p. 6856 - 6863]