Synthesis of β‐Keto Sulfones via Coupling of Aryl/Alkyl Halides, Sulfur Dioxide and Silyl Enolates through Metal‐Free Photoinduced C–X Bond Dissociation

A photoinduced sulfonylative coupling of aryl/alkyl halides, DABCO·(SO2)2 (1,4-diazabicyclo[2.2.2]octane-sulfur dioxide), and silyl enolates under metal-free conditions is developed, giving rise to β-keto sulfones in good yields. This transformation proceeds smoothly at room temperature under ultraviolet irradiation with good tolerance of various functional groups. Aryl iodides/bromides and alkyl halides are all good substrates in the sulfonylative reaction. A plausible mechanism is proposed, which undergoes through a radical process under photoinduced conditions.