CC BY 4.0 · Organic Materials 2024; 06(01): 12-17
DOI: 10.1055/a-2241-0243
Soluble Graphene Nanoarchitectures
Original Article

Pentacene to Octacene: The Limit of Fourfold TIPS-Ethynylation

Nico Zeitter
a   Organisch-Chemisches Institut, Ruprecht-Karls-Universität Heidelberg, Im Neuenheimer Feld 270, 69120 Heidelberg, Germany
,
Nikolai Hippchen
a   Organisch-Chemisches Institut, Ruprecht-Karls-Universität Heidelberg, Im Neuenheimer Feld 270, 69120 Heidelberg, Germany
,
b   Anorganisch-Chemisches Institut, Ruprecht-Karls-Universität Heidelberg, Im Neuenheimer Feld 270, 69120 Heidelberg, Germany
,
Tamara V. Unterreiner
a   Organisch-Chemisches Institut, Ruprecht-Karls-Universität Heidelberg, Im Neuenheimer Feld 270, 69120 Heidelberg, Germany
,
Frank Rominger
a   Organisch-Chemisches Institut, Ruprecht-Karls-Universität Heidelberg, Im Neuenheimer Feld 270, 69120 Heidelberg, Germany
,
a   Organisch-Chemisches Institut, Ruprecht-Karls-Universität Heidelberg, Im Neuenheimer Feld 270, 69120 Heidelberg, Germany
,
a   Organisch-Chemisches Institut, Ruprecht-Karls-Universität Heidelberg, Im Neuenheimer Feld 270, 69120 Heidelberg, Germany
› Author Affiliations


Abstract

Soluble acenes beyond hexacene are rare. Their sensitivity complicates isolation, purification and application in devices. To increase the stability of acenes, functionalization with trialkylsilylethynyl substituents prevents [4 + 4] dimerization and oxidation. At the same time, such acenes are soluble and processible. Here we present the modular synthesis of fourfold tri-iso-propylsilylethynyl-ethynylated pentacenes to octacenes and investigate their optical and redox properties, frontier orbital positions (CV, density functional theory calculations) as well as their stability in solution (UV/vis, NMR spectroscopy). We also investigated their magnetic properties as a function of acene length. Pentacene, hexacene and heptacene are sufficiently stable to serve as semiconductors in thin-film transistors – the octacene rapidly decays to its butterfly dimer evidence by time-dependent NMR spectroscopy and crystal structure analysis.

Primary Data

Compound characterization data are available through heiDATA, the institutional research data repository of Heidelberg University, under https://doi.org/10.11588/data/DDJFGS.



Publication History

Received: 31 August 2023

Accepted after revision: 04 December 2023

Accepted Manuscript online:
09 January 2024

Article published online:
01 February 2024

© 2024. The Authors. This is an open access article published by Thieme under the terms of the Creative Commons Attribution License, permitting unrestricted use, distribution, and reproduction so long as the original work is properly cited. (https://creativecommons.org/licenses/by/4.0/).

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