The reactions of furfuryl alcohols with maleic anhydride

Abstract
The reactions of furfuryl alcohols (1a) and (1b) with maleic anhydride were investigated and, for the first time, conditions defined for the production of intramolecular Diels–Alder adducts. Under basic conditions the adducts (3a, b) yield phthalides in high yield. Furfuryl alcohols (1c) and (8a) afford normal intermolecular Diels–Alder adducts with maleic anhydride.