Direct N‐Acylation of Sulfoximines with Aldehydes by N‐Heterocyclic Carbene Catalysis under Oxidative Conditions

Abstract An active acyl donor intermediate generated in situ from an aldehyde by oxidative N‐heterocyclic carbene (NHC)‐catalysis enables direct acylation of NH‐sulfoximine, affording various N‐acylsulfoximines in excellent yields. The reaction was performed with an inexpensive carbene catalyst and easily accessible bisquinone oxidant. This straightforward transformation demonstrated a broad substrate scope with respect to sulfoximines and aldehydes. Importantly, the method allowed amidation of several unactivated aliphatic aldehydes in good‐to‐moderate yields. Preparative synthesis of N‐acylsulfoximine (up to >2 g) was achieved with this simple method.