I2‐DMSO‐Mediated Cascade Cyclization of β‐Ketosulfoxonium Ylides and β‐Enaminones: Synthesis of Quaternary‐Carbon‐Centered 2‐Hydroxy‐pyrrol‐3(2H)‐ones

A novel I2‐DMSO‐mediated cascade cyclization approach for synthesizing 2‐hydroxy‐pyrrol‐3(2H)‐one scaffold from readily accessible β‐ketosulfoxonium ylides and β‐enaminone derivatives has been developed. Under metal‐free and mild conditions, this cascade transformation facilitates the formation of one C−C bond and one C−N bond in a single reaction vessel, exhibiting a wide range of functional group compatibility. In addition, this method added an active hydroxyl group to a quaternary carbon center.