Visible-Light-Mediated Sulfonylation of Arenes via Catalytic Electron Donor–Acceptor Complex of Thianthrenium Salts

A novel electron donor–acceptor (EDA) complex for photocatalytic sulfonylation has been developed, utilizing catalytic tris(4-methoxyphenyl)amine as the electron donor, thianthrene salts as the acceptor, and DABCO·(SO2)2 as a source of SO2 to generate sulfonyl radicals. This environmentally benign methodology eliminates the need for metal-based photocatalysts, organic dyes, or additives, offering a straightforward and efficient approach for the photocatalytic sulfonylation of arenes via thianthrenation. This method demonstrates good functional group tolerance and broad versatility, making it promising for the late-stage functionalization of a wide range of bioactive molecules. This advancement not only improves the synthetic accessibility of sulfones but also aligns with sustainable chemistry principles by minimizing the use of hazardous reagents and energy-intensive processes.