Substrate‐induced Selective α‐C(sp3)−H Activation of N‐alkyl Amines: Synthesis of Coumarin‐fused Quinolinones under Air

A substrate‐induced synthesis of coumarin‐fused quinolinones is achieved from 4‐(phenylamino)‐2H‐chromen‐2‐ones using N‐alkyl amines as the solvent and a carbon source under air conditions without any catalysts in one pot. This protocol highlights the special roles of 4‐(phenylamino)‐2H‐chromen‐2‐ones which were not only used as reactants but also as an internal oxidant selectively activated N‐α‐C(sp3)−H bond. This reaction features catalyst‐free, broad substrate scopes (N‐alkyl amines 27 examples and quinolinones 24 examples), operationally simple for the one‐step synthesis, and recovery and recycling of the solvent.