A facile Zr-mediated multicomponent approach to arylated allylic alcohols and its application to the synthesis of highly substituted indenes and spiroindenes.

An efficient and one-pot procedure for the synthesis of arylated and stereodefined allylic alcohols has been achieved through zirconium-mediated multicomponent coupling reactions of alkynes, aldehydes (or ketones), and aryl iodides. The subsequent intramolecular Friedel-Crafts reactions of these allylic alcohols catalyzed by Brønsted or Lewis acids afford highly substituted indenes and spiroindenes under extremely mild reaction conditions. This methodology also provided a highly efficient route to the synthesis of spiroindenepiperidines.