Studies on the Intramolecular photocycloaddition of Dihydro-4-pyrones

Article abstract of DOI:10.1016/S0040-4039(00)61747-1

Dihydropyrones 3 shown to undergo intramolecular photocycloaddition in high regioselectivity and good yields.The oxygen-heteroatom plays an important role in the regioselectivity of this reaction and in the subsequent fragmentations.Two possible approaches of the olefin to the cyclic enone have been described.