Electrochemical Formation Of Nitrogen-centered Radicals And Their Applications In Organic Synthesis

Nitrogen-containing compounds are an important class of organic molecules and building blocks,which have the unique effects,such as antibacterial,anti-inflammatory,anti-tumor,anti-parasitic and anti-protozoal,thus widely found in natural products,drug molecules and act as supramolecular constituent units exist in functional materials.Among the series of methods to synthesis the nitrogen-containing compounds,N-centered radicals are an important class of intermediates.Consequently,much efforts have been devoted for their simple,efficient and sustainable formation,especially for the formation of diverse C-N bonds to synthesis various nitrogen-containing compounds.And most of the traditional aza-Michael addition reactions proceed under strong acidic or basic condition or various transition metals involved conditions,even need elevated reaction temperature or long reaction time.It is of great significance for the development of mild and practical methods for the aza-Michael addition reactions.In this paper,nitrogen-centered radicals,which were induced by the use of halogen under electrochemical conditions,were added to deficient alkenes for the realization of aza-Michael addition reactions to synthesis a series of β-amines.Likely,nitrogen-centered radicals react with olefins with allylic leaving groups afforded the allylamines.The paper conducted the following research:(1)Electrochemical synthesis of β-aminesA simple,mild and efficient method of electrochemical aza-Michael addition reactions for the synthesis of β-amines was established.This method is carried out in an undivided cell,exploring the effects of reactions by solvents,types and amount of additives and electrode materials.This method avoided the use of transition metals,strong acids and bases,has the advantages of simple operation,mild conditions,various aza-heterocycles and Ts-protected amines or deficient alkenes were suitable substrates.The experiment of scale up also shows that this method has a potential application value.(2)Electrochemical synthesis of allylaminesA green,economic and efficient method for the synthesis of allylamines was established.In an undivided cell,examing the effects of reactions by solvents,types of additives,temperature and electrode materials.This method avoided the use of transition metals that needed in traditional methods,and adding Na I as not only a redox catalyst but also a supporting electrolyte,no other extra supporting electrolyte.Interrelated experiments indicates that different leaving groups with the different ability of leaving,and this have good references to design the route of the organic synthesis.