FeCl3-catalyzed convenient synthesis of 3-hydroxyphthalates has been achieved by a Diels–Alderreaction of furans with dimethylacetylenedicarboxylate, followed by ring-opening aromatization reaction of the Diels–Alder adducts, 7-oxabicyclo[2.2.1]hepta-2,5-diene derivatives. In addition, 7-azabicyclo[2.2.1]hepta-2,5-diene derivative, derived from N-Boc-pyrrole and dimethylacetylenedicarboxylate, also converted