A palladium-catalyzed reaction, accelerated by microwave heating, forms two alkyl-aryl bonds and one alkenyl-aryl bond in a single vessel. This method produces a range of symmetrical and unsymmetrical tricyclic heterocycles containing oxygen, nitrogen, silicon, or sulfur atoms, starting from a Heck acceptor and an aryl iodide with two attached alkyl halides. The approach was used to synthesize a tricyclic analogue of mescaline.
A one-pot catalytic sequence uses palladium and norbornene to form two alkyl-aryl bonds and one alkenyl-aryl bond simultaneously. Starting from a Heck acceptor and an aryl iodide with two attached alkyl bromides, the method produces a range of symmetrical and unsymmetrical tricyclic heterocycles in good yields. The approach was demonstrated by synthesizing a tricyclic analogue of mescaline.