Three‐Component Synthesis of Quinolines Based on Radical Cascade Visible‐Light Photoredox Catalysis

Synthesis of highly substituted quinolines has been developed based on three‐component radical cascade based on visible‐light photoredox catalysis. This tandem coupling reaction has been coordinated to proceed with high chemoselectivity based on the differential electronic properties of coupling partners. Subjection of electron‐rich β‐aminoacrylates with electron‐deficient halides and alkenes to the optimized conditions leads to the formation of quinolines in good yields after in situ oxidation of tetrahydroquinolines. Detailed mechanistic studies which reveal an unexpected reaction pathway is described.