Photocatalyst-free, visible-light-mediated copper catalysed S-arylation of sulfenamides with aryl thianthrenium salts

The site-selective incorporation of sulfilimine functionalities into aromatic compounds provides a vital strategy for drug discovery in medicinal chemistry. However, the green and sustainable methods for realizing the goal are still limited and urgently need to be developed. Here, we reported a copper-catalyzed S-arylation of sulfenamides with aryl thianthrenium salts irradiated by visible light without the photocatalyst, which exhibited fine functional-group compatibility and gave the desired products with high yields. Notably, the reaction could be performed in PBS buffer and water. Mechanistic investigations revealed that the key to achieving these results is the generation of an EDA complex between sulfenamides and aryl thianthrenium salts under basic conditions. Furthermore, gram-scale reactions and divergent transformations were successfully realized under mild conditions, underscoring the practicality of the methodology.