Photochemical rearrangement of 5,6-epoxy derivatives of the Diels–Alder adduct of levoglucosenone and piperylene

Photolysis of 5,6-epoxy 4-keto derivatives of the Diels–Alder adduct of levoglucosenone and piperylene in C₆H₆–MeOH causes cleavage of the C⁴–C⁵ bond giving product containing vicinal acetone and alkyl acetate moieties, the latter would further transform into 1-alkoxycarbonyl-2-hydroxy-2-methylcyclopentane derivative annulated to 5,8-dioxabicyclo[3.2.1]octane cage.