Steric Tuning of Sulfinamide/Sulfoxides as Chiral Ligands with , Pseudo-, and Pseudo- Symmetries: Application in Rhodium(I)-Mediated Arylation.

A new family of sulfinamide/sulfoxide derivatives was synthesized as chiral bidentate ligands by stereoselective additions of methylsulfinyl carbanions to -butylsulfinylimines. The new ligands, with , pseudo-, and pseudo- symmetries, were successfully assayed in Rh-catalyzed additions of arylboronic acids to activated ketones. The sterically dissymmetric ligand (,,)--[1-(phenylsulfinyl)-3-methylbut-2-yl] -butylsulfinamide turned out to be the optimal one, allowing the 1,4-additions of diverse arylboronic acids, on different α,β-unsaturated cyclic ketones with high chemical yields and enantioselectivities up to >99% ee.