Silver-Mediated Allylation of Aryl Alkenes to Synthesize 1,4-Dienes

An efficient silver-mediated allylation of aryl alkenes is described, which provides a variety of skipped 1,4-dienes. Without the need for other traditional transition metals or gold, this AgOTf-mediated allylation proceeds smoothly with high regio- and stereoselectivity. Mechanistic and computational studies suggest that this silver-mediated allylation takes place via a Friedel-Crafts-type pathway of aryl alkenes to the silver-activated allyl acetates.