Brønsted Base-Catalyzed Domino Annulation of α-oxo-β, γ-Unsaturated Ketones and Malononitrile: Facile Access to Poly-substituted Tetrahydrocyclopenta[b]furanols

An efficient and atom-economical Brϕnsted base-catalyzed domino reaction of α-oxo-β, γ-unsaturated ketone is described. Under the catalysis of 20 mol% K2CO3, both symmetrical cinnamils and unsymmetrical β, γ-unsaturated diketones can react with malononitrile to produce polysubstituted tetrahydrocyclopenta[b]furanols in good to high yields and excellent diastereoselectivity. Three quaternary carbon centers and one tertiary carbon center can be constructed simultaneously, and the reaction can be easily scaled up.