Copper(I)‐Catalyzed Hydroalkoxylation/Hydrogen‐Bonding‐Induced Asymmetric Hetero‐Diels–Alder Cycloaddition Cascade: An Approach to Aromatic Spiroketals

Abstract

One thing leads to another: Bis(benzannelated) 5,6-spiroketal skeletons can be constructed by an efficient cascade process involving an unprecedented CuI-catalyzed intramolecular alkyne hydroalkoxylation and an asymmetric hetero-Diels–Alder cycloaddition. The method yields a series of diversely functionalized spiroketals from two readily available open-chained starting materials in good yields and excellent diastereoselectivities.