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Updated: Jul 29, 2025
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Preparation of a Corannulene-functionalized Hexahelicene by CopperI-catalyzed Alkyne-azide Cycloaddition of Nonplanar Polyaromatic Units
Published on: September 18, 2016
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Xanthene-Separated 24 π-Electron Antiaromatic Rosarin Dimer.
Seokwon Lee1, Yuying Wang2, Ranjan Dutta3
1Department of Chemistry, Spectroscopy Laboratory for Functional π-Electronic Systems, Yonsei University, Seoul, 03722, Korea.
Chemistry (Weinheim an Der Bergstrasse, Germany)
|May 19, 2023
Summary
This study reports a covalently linked rosarin dimer, demonstrating reduced antiaromaticity at low temperatures due to intramolecular interactions. This finding offers insights into the behavior of stacked antiaromatic molecules.
Area of Science:
- Organic Chemistry
- Materials Science
- Computational Chemistry
Background:
- Antiaromatic molecules exhibit high reactivity and narrow HOMO-LUMO gaps.
- Stacking of antiaromatic molecules may induce three-dimensional aromaticity through frontier orbital interactions.
Purpose of the Study:
- To investigate the properties of a covalently linked π-π stacked rosarin dimer.
- To explore the impact of temperature on the antiaromaticity of the dimer.
Main Methods:
- Experimental examination using steady-state absorption and transient absorption spectroscopy.
- Theoretical analysis via quantum chemical calculations, including TD-DFT, AICD, and NICS.
Main Results:
- The rosarin dimer exhibits diminished antiaromaticity at 77 K compared to its monomer.
- Intramolecular interactions between rosarin subunits are identified as the cause for reduced antiaromaticity.
Conclusions:
- Covalently linked π-π stacking can modulate the antiaromatic character of molecules.
- Temperature-dependent intramolecular interactions play a crucial role in the electronic properties of stacked antiaromatic systems.
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