Gold(I)-Catalyzed Synthesis of Furopyrans: Insight into Hetero-Diels-Alder Reactions.

We report herein the synthesis of complex molecules containing furopyran cores through a gold(I)-catalyzed hetero-Diels-Alder cascade reaction. During this process, the diene and the dienophile are produced concomitantly by the action of a single catalyst from a single starting material. Moreover, six bonds, four heterocycles, and four controlled stereogenic centers are formed in a one-step operation. DFT calculations provide the mechanistic basis of this unprecedented reaction.