Simple Units Integration Brings New Reactivity: Neighboring Group Effect in the Synthesis of Polyfunctionalized 5-Alkenyl-3-furanones from γ-Hydroxyl Enal

With the hypothesis of simple units integration to create new reactivities, a strategy for the synthesis of polyfunctionalized 5-alkenyl-3-carbonylfurans from γ-hydroxyl enal and 1,3-dicarbonyl compounds is established, featuring readily available starting materials, high efficiency, good functional groups compatibility, green chemistry with high atom economy and only water release, etc., to provide a series of polyfunctionalized 5-alkenyl-3-carbonylfurans, which could be applied to the late-stage functionalization of naturally occurring compounds and bioactive molecules, as well as the transformation to pyrroles and polycyclic aromatic hydrocarbon via electrocyclic reaction. The γ-hydroxyl has played an important role in the unexpected process of ring opening isomerization of 2H-pyran to furanones, as confirmed by detailed mechanistic studies.