Transition Metal-free Alkyl Ketone-directed Site-selective Monoiodination Of Arenes

Aryl iodide is a class of important organic compounds,and it has been widely applied in organic synthesis,pharmaceutical,molecular recognition and materials chemistry.Therefore,it has attracted the interest of organic synthetic communities.To solve the address of excellent regioselective and chemoselective of aromatics iodination,transition metal catalyzed,directing group(DG)assisted iodination of arylring has become a popular synthetic strategy,resulting in the development of numerous synthetic strategies.However,the transition metal-free site-selective C(sp~2)-H iodination of arenes has been seldom studied.This thesis mainly focuses on the transition metal-free selective mono-iodination of arenes using alkyl ketone as a weakly DG.This dissertation was divided into two chapters:chapter 1:Directing group(DG)assisted site-selective C-H iodination reaction of aryl compounds has been reviewed.chapters 2:After extensive investigation of reaction conditions,such as reaction solvent,iodinated reagent,oxidant,and reaction concentration,ultimately,we developed a general selective iodination of arenes using alkyl ketone as a weakly DG under transition-metal free conditions,generating iodoarenes in good to excellent yields with excellent site selectivity.In this new transformation,the 0.5 equivalent of I2 and the 0.8 equivalent of phenyliodosodiacetate(PIDA)was served as iodine source and oxidant,respectively,hexafluoroisopropanol(HFIP)as reaction solvent.The protocol features a wide range of aryl-substituted ketones,short reaction time,mild reaction conditions,and scalable synthetic procedure.Additionally,a possible reaction mechanism was proposed based on a series of designed control experiments.