Aluminum-Catalyzed Intramolecular Vinylation of Arenes by Vinyl Cations

This study addresses the challenges associated with vinyl cation generation, a process that traditionally requires quite specific counterions. Described herein is a novel intramolecular vinylation of arenes catalyzed by aluminum(III) chloride, utilizing practical conditions and readily available vinyl triflates derived from 2-aceto-3-arylpropionates. Comprehensive experimental data support diverse carbocycle synthesis, exemplified by indenes and higher analogues. Control experiments verify the applicability of the vinylation protocol, and synthetic applications showcase a potent tubulin polymerization inhibitor with anticancer properties. Density functional theory computations reveal a Lewis-acid-driven mechanism involving triflate moiety abstraction to generate a reactive vinyl cation.