Chemistry Reference
In-Depth Information
Beyond Pentacenes: Synthesis and Properties
of Higher Acenes
Christina T¨nshoff and Holger F. Bettinger
Abstract Acenes consist of linearly annulated benzene rings. Their reactivity
increases quickly with increasing chain length. Therefore acenes longer than
pentacene are very sensitive towards oxygen in the presence of light and thus
these molecules have not been well studied or have remained elusive in spite of
synthetic efforts dating back to the 1930s. This review gives an historical account of
the development of the chemistry of acenes larger than pentacene and summarizes
the recent progress in the field including strategies for stabilization of higher acenes
up to nonacene.
Keywords Acenes
Alternant hydrocarbon
Polymer
Spectroscopy
Synthesis
Contents
1 Introduction ................................................................................... 2
2 Hexacenes ..................................................................................... 3
2.1 Parent Hexacene . . . ..................................................................... 3
2.2 Substituted Hexacenes . ................................................................ 7
3 Heptacenes .................................................................................... 9
3.1 Parent Heptacene . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 9
3.2 Substituted Heptacenes ................................................................. 14
4 Octacene and Nonacene ...................................................................... 21
4.1 Parent Octacene and Nonacene . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 21
4.2 Silylethynyl Substituted Nonacenes . . . ................................................ 23
4.3 Thioaryl Substituted Nonacenes . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 26
5 Conclusions and Outlook ..................................................................... 28
References . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . 28
