One-Pot Allylation–Intramolecular Vinylogous Michael Addition–Isomerization Cascade of <i>o</i>-Hydroxycinnamates and Congeners: Synthesis of Substituted Benzofuran Derivatives
intramolecular vinylogous Michael addition leading to the synthesis of heterocycles has been disclosed. Base-promoted one-pot sequential O-allylation of o-hydroxy-cinnamates or -cinnamonitrile or -chalcones with γ-bromocrotonates followed by an intramolecular conjugate addition of vinylogous Michael donors resulted in the formation of highly substituted benzofuran derivatives in good to excellent yields. The intramolecular