Stereoselective Sequential Diels–Alder Reactions on a Cyclic Furan Trimer for the Construction of an Asymmetric Scaffold

Multiple Diels–Alder reactions are a powerful method to construct large asymmetric scaffolds, but these reactions often produce numerous isomers. We now report a triple Diels–Alder reaction between a cyclic furan trimer and N-substituted maleimides, achieving selective synthesis of a single asymmetric tris-adduct. The stereoselectivity of cycloaddition to π-extended furan derivatives was clarified by the experimental analysis of intermediates and theoretical calculations. Furthermore, the potential of the method to synthesize a chiral, optically active molecule was demonstrated.