Palladium-Catalyzed Tandem Synthesis of Fused Spiroquinolinones from Bicyclobutyl Amides

A palladium-catalyzed tandem cyclization and amination of bicyclobutyl (BCB) amides has been disclosed for the assembly of fused spiroquinolinone skeletons. By using di- t -butyldiaziridinone as the amination reagent, the reaction of bicyclobutyl amides with perfluoroalkyl iodides proceeded efficiently to furnish a broad range of fused spiroquinolinone derivatives in high yields. Notably, this strategy enables the rapid incorporation of a fused ring at the 4,5,10-position and a spiro ring at the 3-position of the quinolinone core.