An open-and-shut strategy: preparation of benzo-fused indanes by ring-opening of a vinylogous acyl triflate and metal-catalyzed Asao-Yamamoto benzannulation

A two-step strategy for the synthesis of benzo-fused indanes is outlined herein. The strategy draws on two independent methodologies: the tandem addition/fragmentation of vinylogous acyl triflates (VATs) and the intramolecular benzannulation of o-alkynylphenyl ketones. Reduction of this strategy to practice involves the use of aryltriazenes as masked aryl iodides; a synthetic equivalent of 2-iodophenyllithium is featured. Benzo-fused indanes are prepared efficiently and in high yield.