Oligomerization of the Cu(II) and Ni(II) tetraazaannulene complexes: A pulse radiolysis study of the associated reaction mechanism

• Published in: Inorganica Chimica Acta 2009-05, Vol.362 (7), p.2177-2182
• Main Authors: Villagran, M., Muena, J.P., Costamagna, J., Zagal, J., Lappin, A.G., Ferraudi, G.
• Format: Article
• Language: English
• Subjects: Cu(II) and Ni(II) tetraazaannulene complexes; Oligomerization; Pulse radiolysis; Reaction mechanism
• ISSN: 0020-1693; 1873-3255
• DOI: 10.1016/j.ica.2008.09.051

The oligomerization of [Cu II(H x (tmdnTAA))] x + ( x = 0, 1, 2 and (tmdnTAA)) 2− is 2,4,9,11-tetramethyl-dinaphto[14]-2,4,6,9,11,13-hexaeneN 4) was initiated in homogeneous solution via the reaction of this Cu(II) complex with pulse radiolytically generated N 3 radicals. The reaction produces Cu(III) intermediates which are rapidly converted to Cu(II) ligand–radical species. The oligomerization of [Cu II(H x (tmdnTAA))] x + ( x = 0, 1, 2 and (tmdnTAA)) 2− is 2,4,9,11-tetramethyl-dinaphto[14]-2,4,6,9,11,13-hexaeneN 4) was initiated in homogeneous solution via the reaction of this Cu(II) complex with pulse radiolytically generated N 3 radicals. The reaction produces Cu(III) intermediates which are rapidly converted to Cu(II) ligand–radical species. In contrast to the mechanism proposed for the electrochemical oligomerization, where the local concentration of radicals is probably high, the reaction kinetics in homogeneous solution is propagated by a process where the Cu(II) ligand–radical precursors react with [Cu II(H x (tmdnTAA))] x +.