Paired electrolysis enables weak Brønsted base-promoted amination of arenes with N,N-dialkyl formamides as the amine source

Abstract

Herein, a paired oxidative and reductive electrolysis enabled weak Brønsted base-promoted amination of arenes with N,N-dialkyl formamides as the amine source is described. The transformation proceeds smoothly under mild conditions with a broad range of benzoxazoles, quinones and hydroquinones, providing valuable and versatile arylamines in moderate to good yields without stoichiometric amounts of chemical oxidants or addition of transition metals. Mechanistic studies revealed that acetate salts used as weak Brønsted bases promote the oxidation of DMF to form aminyl radicals; meanwhile, arenes are reduced on the cathode to give the corresponding radical anions. Density functional theory calculations were conducted to rationalize the weak Brønsted base-promoted regioselectivity of the electrooxidation of N,N-dialkyl formamides observed in the reaction. A preliminary investigation was also conducted on the antibacterial properties and optical properties of the products.