Nucleophilic Allylic Alkylation and Hydroarylation of Allenes

The synthesis of benzylic stereocenters containing vinyl units is a stimulating and challenging target for organic chemists, due to the wide distribution of this key structural motif in biologically active natural products and pharmaceutical compounds. Aromatic electrophilic allylic substitution and intramolecular hydroarylation of allenes are the most promising synthetic routes to framework. In this chapter, a collection of inter- as well as intramolecular approaches working under catalytic regime, is presented with particular emphasis to their scope and limitations. Recent developments in the field of asymmetric Friedel-Crafts type allylic alkylation (ee constantly higher the 90%) are also presented. The known chiral catalysts employed, for enantioselective FC-allylation of arenes, are Ir, Pd, Pt and Au-organometallic species. Interestingly, no examples of organocatalyzed allylation of arenes have been described to date.