Transition-metal-free Catalytic Transformations Of Diazo Quinones

With chemical properties of aromatization and feasible introduction of phenol/naphthol structures,diazo quinones（quinone diazides）are widely used in various fields.In the past few decades,a series of reactions catalyzed by transition-metal have been mainly reported.These reactions are carried out by C-H insertion or metal carbene migration insertion,most of the reaction site selectivity is determined by directing groups.Herein,various transition metal catalyzed transformations of diazo quinones in recent years are summarized.Transition-metal-free catalytic transformations of diazo quinones remain highly desirable.Thus,this paper mainly investigates the transformations of diazo quinones using common acids or bases.This paper is divided into the following three chapters:Chapter 1:Research progress on transition metal-catalyzed transformations of diazo quinonesThis section mainly summarizes the relevant conversion reactions in recent years according to the types of transition metals,such as Rh（III）/Rh（III）,Ir（II）,Pd（0）/Pd（II）,Fe（III）,Ru（II）,Cu（II）.The reaction uses the unique chemical properties of diazo quinones to construct C-C bonds by forming metal carbene during the migration insertion reaction.Chapter 2:Transformation reaction of base-catalyzed diazo quinones to hydrazonesIn this study,we used K₂CO₃ as a catalyst which is cheap and readily available.The transformation occurs under mild reaction conditions with high atomic economy,avoids the use of transition-metals,and is tolerated with various functional groups.Chapter 3:Study on the transformation reaction of acid-catalyzed diazo quinones to synthesize azo compoundsIn this study,we have developed a transition-metal-free C（sp²）-N bond forming reaction by the cross-coupling of diazo quinones with electron-rich aromatic compounds.The reaction is catalyzed by Tf OH and successfully obtained a variety of symmetric aromatic azo compounds under mild reaction conditions with high atom economy.This method introduces an azo group at the ortho-site of the phenolic hydroxyl group.