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

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 >2g) was achieved with this simple method.