Electrochemical Oxidative C-H/N-H Coupling Between ?-Lactams And Anilines

Carbon–nitrogen bond formation is important in synthetic organic chemistry,due to the high prevalence of the nitrogen-containing compounds in natural products,pharmaceutical-,and materials science.The oxidative sp3 C–H bond activation is an important method for the construction of nitrogen-containing compounds,which has been developed in recent years.However,most of the nitrogen containing substrates were limited to amides,sulfonamides,azoles and anilines.The direct use of anilines,a group of substrates susceptible to oxidization as N sources through oxidative sp3 C-H bond activation remains challenging and typically the substrate scope is limited.In this paper,a review of electrochemistry methods to construct C-N bonds was presented,and the recent developed synthetic methods for constructing C-N bonds via oxidative sp3 C–H bond activations adjacent to a nitrogen atom were also introduced.On the basis of previous work,and the advantages of electrochemistry compared with traditional chemistry.we envisioned that the construction of C-N bond could be accomplished via electrochemistry oxidation of sp3 C–H bond adjacent to a nitrogen atom.In this paper,reaction conditions such as current,electrolyte,solvent were screened.We found that in an undivided cell,using Pt wire as anode and Pt foil cathode,acetonitrile as solvent and ammonium perchlorate(0.24 M)as electrolyte,the reaction of ?-lactams and anilines proceeded in excellent yield in the constant current without transition metals.A wide range of anilines either is bearing electron-deficient groups or electron-rich groups on the aromatic rings,can give corresponding products.Both heterocyclic aromatic primary amine and sterically hindered substrates were suitable for this transformation.Notably,iodiosubstituted aniline could also give the desired products in moderate yield.In this paper,the reaction mechanism has been studied in detail.It is speculated that 1-methylpyrrolidin-2-one was oxidized on the anode to form intermediates and then the intermediate was trapped by a nucleophile to give the target product.