Iodine/DMF-Mediated Regioselective Sulfenylation Using Arenediazonium Tosylates and Sodium Metabisulfite: An Easy Access to 3‑Arylthioindoles

A practical C3 sulfenylation of indoles has been accomplished using arenediazonium tosylates and sodium metabisulfite, with a key role of iodine/DMF combination in the reaction. The method involves scarce use of sodium metabisulfite as a divalent sulfur source and offers an array of structurally diverse 3-arylthioindoles in high yields under operationally simple transition-metal-free and mild conditions.