Study On Lewis Acid-Catalyzed [2+2] Cycloaddtion

4H-Chromen-4-one and its derivatives are important organic heterocyclic compounds, which present various bioactivities of concern in organic synthesis. We developed a cascade method to construct2-aryl-3-alkoxycarbonyl chromones using3-phenylpropiolate through [2+2] cycloaddition and O-Michael addition.2-Aryl-3-alkoxycarbonyl chromones were effectively constructed from aldehydes and3-(2-(methoxymethoxy)phenyl)propiolates via Lewis acid catalyzed formal (2+2) cycloaddition, ring-opening of oxetene, oxa-Michael addition, and DDQ oxidation with high atom efficiency. This reaction expanded the range of applications of the substrate, which is expected to become a new method to the synthesis of flavonoid drug.