Palladium-mediated cascade or multicomponent reactions: A new route to carbo- and heterocyclic compounds

In recent years, new processes based on transition-metal-mediated intramolecular addition reaction of heteronucleophiles and stabilized carbon nucleophiles to unactivated alkenes and alkynes have been developed in our laboratory. In this article, we summarize a number of recent synthetic applications of these new processes. Emphasis is placed on the development of multicomponent reactions based on a Pd-mediated intramolecular cyclization coupled with a carbon-carbon bond-forming reaction. Applications of this methodology to the synthesis of natural lignans are also reported.