Synthesis of fused α-methylene-γ-butyrolactone derivatives through pyridine-induced addition of phenols to dimethyl acetylenedicarboxylate

The reaction between dimethyl acetylenedicarboxylate and various phenols including phenol, 1-naphthol, 2-naphthol, 8-hydroxyquinoline, 1,6-dihydroxynaphthalene, cathechol, hydroquinone and resorcinol in the presence of catalytic amounts of pyridine leads to fused α-methylene-γ-butyrolactone derivatives in good yields.