Visible-light-induced arylation via an electron–donor–acceptor complex: a catalyst-free approach for the synthesis of N-(hetero)aryl sulfonamides

Abstract

In the pharmaceutical sector, functionalized aryl sulfonamides are fundamental building blocks. The photoexcitation of aryl(hetero)diazonium salts and sulfonamides enabled this strategy under visible-light irradiation through an EDA complex used to carry out a one-step synthesis without a catalyst. This approach tolerated various functional groups of primary sulfonamides and (hetero)aryl diazonium salts, frequently found in modern medications and pharmacological intermediates. This method also enabled the direct arylation of secondary sulfonamides. The mechanistic study showed that the formed electron–donor–acceptor EDA complex and sulfonamide radical rapidly interact with the aryl radical intermediate through radical coupling to generate the desired product.