A new route to 4-hydroxytetralones and 1-naphthols

Abstract

The lithium salts, derived from position 3 of phthalides by treatment with hindered bases, participate in Michael addition reactions with a variety of conjugated olefins. For singly-activated olefins the conjugate anion reacts intramolecularly with the lactone group to produce 4-hydroxytetralones in moderate to good yield. Dehydration of these hydroxytetralones, by brief treatment with acid, produces the corresponding α-naphthol. Substituted phthalides react similarly making the method a general one for the production of substituted α-naphthols.