Direct Asymmetric Michael Addition of Thioether-based Aryl Sulfanyl-propan-2-one to Nitroalkenes Catalyzed by a Chiral Amine-Thiourea Bifunctional Organocatalyst

Although the organocatalytic direct asymmetric Michael reactions of carbonyl compounds to nitroalkenes have been investigated intensely, the Michael reaction of the thioether-based donors remains a rather undeveloped field. This work concerns the asymmetric Michael addition of aryl sulfanyl-propan-2-one to nitroalkenes with benzoic acid as an additive, and chiral amine-thiourea as a bifunctional organocatalyst. The reactions provided the highly functionalized chiral adducts with excellent enantioselectivities (up to 96% ee) and good yields. Moreover, the further transformed products exhibited excellent diastereoselectivity.