Enantioselective Iridium-Catalyzed Allylic Substitutions with Hydroxamic Acid Derivatives as N-Nucleophiles

Enantioselective Ir-catalyzed allylic aminations with hydroxamic acid derivatives are described. Catalysts were prepared in situ from [Ir(cod)Cl](2) or [Ir(dbcot)Cl](2), a phosphoramidite and base. In addition, pure (pi-allyl)Ir complexes containing cod or dbcot as auxiliary ligands were used. Very high degrees of regio- and enantioselectivity were achieved. The reaction products were transformed Into piperidine derivatives suited as precursors for aza-sugars.