Diastereo- and Enantioselective Iridium-Catalyzed Allylation of Cyclic Ketone Enolates: Synergetic Effect of Ligands and Barium Enolates

We
report asymmetric allylic alkylation of barium enolates of cyclic
ketones catalyzed by a metalla­cyclic iridium complex containing
a phosphor­amidite ligand derived from (R)-1-(2-naphthyl)­ethylamine.
The reaction products contain adjacent quaternary and tertiary stereocenters.
This process demonstrates that unstabilized cyclic ketone enolates
can undergo diastereo- and enantio­selective Ir-catalyzed allylic
substitution reactions with the proper choice of enolate counter­cation.
The products of these reactions can be conveniently transformed to
various useful poly­carbo­cyclic structures.