Investigation of 2,6-disubstituted N,N,N′,N′-tetramethyl-p-phenylenediamines as precursors/building blocks for molecular magnets

Abstract

The synthesis of 2,6-disubstituted N,N,N′,N′-tetramethyl-p-phenylenediamines (R = Cl, Br, I, CN, or CCSi(CH3)3), potential precursors/building blocks for molecular magnets, is presented. In addition to standard methods (1H NMR, 13C NMR, MS, IR, UV), the products were also characterised by means of cyclic voltammetry. Completely reversible electrochemical behaviour was observed for both the CN and the CCSi(CH3)3 derivatives. Moreover, the corresponding radical cations and the dications were observed by cyclic voltammetry for these compounds. The first oxidation step of the Cl and the Br derivatives was also found to be reversible, although a chemical side reaction was detected after oxidation to the corresponding dication. The radical cation could not be detected for the I derivative. In this case direct oxidation to the dication followed by a chemical reaction was observed.