Catalyst-free, facile, one-pot and safe waste synthesis of new benzofurans via electrochemical methods under ECEC mechanism

The electro-oxidation of N,N,N',N'-Tetramethyl-benzene-1,4-diamine (1a) is carried out in the presence of cyanoacetates (3a–c), as nucleophiles, in a phosphate buffer solution (0.2 M, pH 7) mixed with EtOH using voltammetric methods. The results indicate that quinone-imine 2a derived from N,N,N',N'-Tetramethyl-benzene-1,4-diamine participates in a 1,4-Michael-type addition reaction with cyanoacetate derivatives form the new benzofuran derivatives (7a–c) in good yields and with high purities using a simple, catalyst-free, clean, fast and one-pot electrochemical method using six carbon electrodes.