Substrate or Solvent-Controlled PdII-Catalyzed Regioselective Arylation of Quinolin-4(1H)-ones Using Diaryliodonium Salts: Facile Access to Benzoxocine and Aaptamine Analogues

Regioselective C3, C5, and C8 arylation of quinolin-4(1H)-ones have been accomplished either by substrate-control or by tuning the reaction solvent. A variety of aryl(mesityl)iodonium triflates could smoothly deliver arylated products in good to excellent yields. Additionally, it offers great flexibility by arylating medicinally potent quinolone related heterocycles such as acridin-9(10H)-one, and phenanthridin-6(5H)-one under standard reaction conditions. This strategy was further extended with diphenyleneiodonium triflate to access oxacine fused quinolines. The post-modifications of synthesized products enhance the further utility of this protocol in organic synthesis. To the best of our knowledge, this is the first report on C5 arylation of quinolin-4(1H)-ones using iodine(III) reagents.