Cascade Radical Cyclization of Propargylamines for Functionalized 3‐Arylthioquinoline Formation

A novel and efficient strategy for the direct synthesis of 3‐arylthioquinoline derivatives via radical induced tandem cyclization of propargylamines with diaryl disulfides was developed. This protocol undergoes a cascade sulfuration/ cyclization/ oxidation/ aromatization pathway to afford the desired products in a broad substrate scope using readily available starting materials under mild conditions. Based on this strategy, we further modified 3‐arylquinolines to obtain two novel deep blue fluorescent molecules, QLSCz and QLSTCz, with good optical properties through two‐step synthesis by oxidation and electron donor modification.