If the results of the measurements performed at the PEPR Facility are included in a publication, the following statement shall be added to the Acknowledgments section: "The EPR measurements were performed at the Centre for Pulse EPR at Imperial College London (PEPR), supported by the EPSRC grant EP/T031425/1."

We would be grateful if the Facility could be informed of the submission by sending an e-mail to m.roessler@imperial.ac.uk and a.collauto@imperial.ac.uk.

Citation

BibTex format

@article{Rimmele:2021:10.1039/d1qo00901j,
author = {Rimmele, M and Nogala, W and Seif-Eddine, M and Roessler, M and Heeney, M and Plasser, F and Glöcklhofer, F},
doi = {10.1039/d1qo00901j},
journal = {Organic Chemistry Frontiers},
pages = {4730--4745},
title = {Functional group introduction and aromatic unit variation in a set of πconjugated macrocycles: revealing the central role of local and global aromaticity},
url = {http://dx.doi.org/10.1039/d1qo00901j},
volume = {8},
year = {2021}
}
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RIS format (EndNote, RefMan)

TY  - JOUR
AB  - π-Conjugated macrocycles are molecules with unique properties that are increasingly exploited for applications and the question of whether they can sustain global aromatic or antiaromatic ring currents is particularly intriguing. However, there are only a small number of experimental studies that investigate how the properties of πconjugated macrocycles evolve with systematic structural changes. Here, we present such a systematic experimental study of a set of [2.2.2.2]cyclophanetetraenes, all with formally Hückel antiaromatic ground states, and combine it with an in-depth computational analysis. The study reveals the central role of local and global aromaticity for rationalizing the observed optoelectronic properties, ranging from extremely large Stokes shifts of up to 1.6 eV to reversible fourfold reduction, a highly useful feature for charge storage/accumulation applications. A recently developed method for the visualization of chemical shielding tensors (VIST) is applied to provide unique insight into local and global ring currents occurring in different planes along the macrocycle. Conformational changes as a result of the structural variations can further explain some of the observations. The study contributes to the development of structure–property relationships and molecular design guidelines and will help to understand, rationalize, and predict the properties of other πconjugated macrocycles.
AU  - Rimmele,M
AU  - Nogala,W
AU  - Seif-Eddine,M
AU  - Roessler,M
AU  - Heeney,M
AU  - Plasser,F
AU  - Glöcklhofer,F
DO  - 10.1039/d1qo00901j
EP  - 4745
PY  - 2021///
SN  - 2052-4110
SP  - 4730
TI  - Functional group introduction and aromatic unit variation in a set of πconjugated macrocycles: revealing the central role of local and global aromaticity
T2  - Organic Chemistry Frontiers
UR  - http://dx.doi.org/10.1039/d1qo00901j
UR  - https://pubs.rsc.org/en/Content/ArticleLanding/2021/QO/D1QO00901J#!divAbstract
UR  - http://hdl.handle.net/10044/1/89893
VL  - 8
ER  -
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