Acenes [n]ac, consisting of linearly fused benzene rings, are important materials for organic electronics and are currently in the focus of materials research.[1] Reactivity increases among the acene series significantly with length,[2] causing instability for acenes longer than hexacene.
The acenes beyond hexacene are assumed to be notoriously unstable,[3] but are valuable for studying the transition from stable organic molecules to zig-zag graphene nanoribbons that may be metallic in the limit of infinite length. To allow experimental investigations of larger acenes,[4] we have developed synthetic access to acenes up to undecacene [11]ac.[5] We report on the properties of those higher acenes, in particular with respect to their optical and magnetic properties.
References:
[1] a) J. E. Anthony, Angew. Chem. Int. Ed. 2008, 47, 452-483;
b) J. E. Anthony, Chem. Rev. 2006, 106, 5028-5048;
c) F. Ortmann, K. S. Radke, A. Günther, D. Kasemann, K. Leo, G. Cuniberti, Adv. Funct. Mater. 2015, 25, 1933-1954.
[2] D. Biermann, W. Schmidt, J. Am. Chem. Soc. 1980, 102, 3163-3173.
[3] a) R. Einholz, H. F. Bettinger, Angew. Chem., Int. Ed. 2013, 52, 9818-9820;
b) R. Einholz, T. Fang, R. Berger, P. Grüninger, A. Früh, T. Chassé, R. F. Fink, H. F. Bettinger, J. Am. Chem. Soc. 2017, 139, 4435-4442.
[4] H. F. Bettinger, C. Tönshoff, Chem. Rec. 2015, 15, 364-369.
[5] a) C. Tönshoff, H. F. Bettinger, Angew. Chem., Int. Ed. 2010, 49, 4125-4128;
b) B. Shen, J. Tatchen, E. Sanchez-Garcia, H. F. Bettinger, Angew. Chem. Int. Ed. 2018, 57, 10506-10509.
Institut für Organische Chemie, Tübingen, Germany