PHOTOCHEMICAL REARRANGEMENT OF 3-PHENYLATED 2(3H)-OXEPINONES IN ACIDIC MEDIA. FORMATION OF 5-STYRYL-2(5H)-FURANONES

The sensitized photolysis of 3-phenylated 2(3H)-oxepinones in methylene chloride containing acids gives 5-styryl-2(5H)-furanones as the major products. The 1,5-phenyl migrated products, 7-pheny1-2(7H)-oxepinones, are proposed as the most plausible initial photoproducts.