Photocatalyzed Site-Selective Formal β-C(sp ³ )–H Sulfonylation of Ketones with Sulfinates

Herein, we report a photocatalytic strategy for the site-selective formal β-C(sp³)-H sulfonylation of ketones. This method operates under mild conditions and exhibits broad functional group compatibility. Its utility is demonstrated through scalable synthesis and the late-stage functionalization of complex molecules. Mechanistic investigations suggest a reaction pathway involving a photoinduced hydrogen atom transfer (HAT) step, followed by copper-mediated reductive elimination. This protocol provides a direct route to valuable β-sulfonyl ketones from readily available starting materials and inexpensive reagents.