Gold(III) chloride-catalyzed addition reactions of electron-rich arenes to methyl vinyl ketone

For the reaction of alpha,beta-unsaturated ketones with electron-rich arenes catalyzed by gold(III) chloride both, a Friedel-Crafts-type mechanism and an initial metallation, are evaluated. Gold(III) chloride has proven to be an efficient catalyst under very moderate reaction conditions, however, in the case of sterically demanding products HBF4 turned out to be the superior catalyst.