Aerobic oxidation of 1, 4, 4a, 10a-tetrahydro-1, 4-alkano-5, 10-anthraquinones and thiophene-analogues in dichloromethane–DBU yielded the corresponding dihydroalkanoquinones which, depending on their structures, react with in situ generated hydroperoxide anion to give quinone epoxides and/or hydroperoxides. The calcium hydroxide-induced rearrangement of quinone epoxides yielded furan-containing angular ...