[2.2.2.2]Paracyclophanetetraenes (PCTs): cyclic structural analogues of poly(p‑phenylene vinylene)s (PPVs)
File(s)
Author(s)
Pletzer, Matthias
Plasser, Felix
Rimmele, Martina
Heeney, Martin
Glöcklhofer, Florian
Type
Journal Article
Abstract
<b>Background</b>: Poly( <i>p</i>-phenylene vinylene)s ( <b>PPV</b>s) and [2.2.2.2]paracyclophanetetraene ( <b>PCT</b>) are both composed of alternating π-conjugated <i>para</i>-phenylene and vinylene units. However, while the former constitute a class of π-conjugated polymers that has been used in organic electronics for decades, the latter is a macrocycle that only recently revealed its potential for applications such as organic battery electrodes. The cyclic structure endows <b>PCT</b> with unusual properties, and further tuning of these may be required for specific applications. <b>Methods</b>: In this article, we adopt an approach often used for tuning the properties of <b>PPV</b>s, the introduction of alkoxy (or alkylthio) substituents at the phenylene units, for tuning the optoelectronic properties of <b>PCT</b>. The resulting methoxy- and methylthio-substituted <b>PCT</b>s, obtained by Wittig cyclisation reactions, are studied by UV-vis absorption, photoluminescence, and cyclic voltammetry measurements, and investigated computationally using the visualisation of chemical shielding tensors (VIST) method. <b>Results</b>: The measurements show that substitution leads to slight changes in terms of absorption/emission energies and redox potentials while having a pronounced effect on the photoluminescence intensity. The computations show the effect of the substituents on the ring currents and chemical shielding and on the associated local and global (anti)aromaticity of the macrocycles, highlighting the interplay of local and global aromaticity in various electronic states. <b>Conclusions</b>: The study offers interesting insights into the tuneability of the properties of this versatile class of π-conjugated macrocycles.
Date Issued
2021-01
Date Acceptance
2022-04-05
Citation
Open Research Europe, 2021, 1 (111), pp.111-111
ISSN
2732-5121
Publisher
F1000 Research Ltd
Start Page
111
End Page
111
Journal / Book Title
Open Research Europe
Volume
1
Issue
111
Copyright Statement
© 2022 Pletzer M et al. This is an open access work distributed under the terms of the Creative Commons Attribution License, which permits unrestricted use, distribution, and reproduction in any medium, provided the original work is properly cited.
License URL
Sponsor
Commission of the European Communities
EPRSC
Engineering & Physical Science Research Council (EPSRC)
FWF Austrian Science Fund (FWF)
Identifier
https://open-research-europe.ec.europa.eu/articles/1-111/v2
Grant Number
796024
EP/V048686/1
EP/V048686/1
J 4463
Publication Status
Published
Date Publish Online
2022-03-10