Tandem Synthesis of 3,5‐Dihydrocyclopenta[de]quinolin‐2(1H)‐one Scaffolds from α‐Bromocarbonyls and α‐Diazoesters under Copper and Palladium Catalysis

A Cu/Pd‐catalyzed tandem radical cyclization and C‐H activation/carbene insertion of α‐bromocarbonyls with α‐diazoesters has been developed for the construction of fused quinolin‐2(1H)‐one scaffolds. The reaction proceeded well to afford a series of 3,5‐dihydrocyclopenta[de]quinolin‐2(1H)‐one derivatives. Additionally, bioactive molecules such as sesamol and estrone could be modified by using this method.