Sequential Photoredox Catalysis for Cascade Aerobic Decarboxylative Povarov and Oxidative Dehydrogenation Reactions of N‐Aryl α‐Amino Acids

Abstract A visible‐light‐driven sequential photoredox catalysis to allow N ‐aryl α‐amino acids to experience efficient cascade aerobic decarboxylative Povarov and oxidative dehydrogenation (ODH) reactions is described. With a dicyanopyrazine‐derived chromophore (DPZ) as a photoredox catalyst in both transformations, two series of valuable azaarenes, i. e., 4‐amino tetrahydroquinolines (THQs) and quinolines, were obtained in satisfactory yields featuring diverse 2‐ and 2,3‐substituent patterns. To enable the ODH reaction of 4‐amino THQs, a cooperative catalysis with N ‐hydroxyphthalimide was developed. Additionally, an unprecedented synthesis of chiral N ‐amino‐2‐methyl THQs with high enantioselectivities was realized. magnified image