Sugar-based monodentate phosphoramidite ligands for Cu-catalyzed enantioselective conjugate addition to enones

In this paper we present new, monodentate phosphoramidite ligands based on amines derived from the easy available monosaccharide d-xylose and BINOLs. Ligands were used for copper-catalyzed conjugate addition to acyclic and cyclic enones. The highest enantioselectivity achieved in this study was 77% ee for the conjugate addition to trans-chalcone, which is comparable to the best results published to date for phosphoramidite ligands based on carbohydrate-derived amines.