Reaction of aromatic amines with Cu(ClO4)2 in acetonitrile as a facile route to amine radical cation generation

This Letter describes a very simple and effective method for the generation and study of radical cations of aromatic amines. It is shown that simple mixing of micro molar solutions of aromatic amines with micro molar amounts of Cu(ClO4)2 in acetonitrile solution leads to formation of amine radical cations in good yields. The radical cations thus generated are unequivocally characterized by their absorption and electron spin resonance spectra. It is proposed that the radical cations are formed through the donation of an electron from the amines to Cu2+.