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Published on: June 10, 2021
Isomerism tunes the diradical character of difluorenopyrroles at constant Hückel-level anti-aromaticity
Ryotaro Moriyasu1, Sergio Moles Quintero2, Carlos J Gómez-García3
1Department of Materials Chemistry, School of Engineering, The University of Shiga Prefecture 2500 Hassaka-cho Hikone Shiga 522-8533 Japan kato.s@mat.usp.ac.jp.
Abstract:
A new diradical based on diindenocarbazole or difluorenopyrrole was synthesized and experimentally characterized by optical, electrochemical, and magnetic techniques, as well as quantum chemical calculations. The isomerism of these structures tunes the diradical character and the associated properties, representing a unique case of such important modulation. A full study of the electronic structure was carried out considering the perturbative interactions between different canonical forms as well as the anti-aromatic character of the molecular cores. Such a study reveals how we can tune diradical character simply by reorganizing the bonding patterns at constant chemical costs (composition).
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