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

Abstract

A substrate‐induced synthesis of coumarin‐fused quinolinones is achieved from 4‐(phenylamino)‐2<i>H</i>‐chromen‐2‐ones using <i>N</i>‐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)‐2<i>H</i>‐chromen‐2‐ones which were not only used as reactants but also as an internal oxidant selectively activated <i>N</i>‐<i>α</i>‐C(sp<sup>3</sup>)–H bond. This reaction features catalyst‐free, broad substrate scopes (<i>N</i>‐alkyl amines 27 examples and quinolinones 24 examples), operationally simple for the one‐step synthesis, and recovery and recycling of the solvent.