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Published on: April 19, 2019
Reversible σ-dimerizations of persistent organic radical cations
Xiaoyu Chen1, Xingyong Wang, Zhaoyi Zhou
1State Key Laboratory of Coordination Chemistry, School of Chemistry and Chemical Engineering, Nanjing University, China.
Angewandte Chemie (International Ed. in English)
|November 23, 2012
Summary
Stable radical cations undergo reversible dimerization. This study presents reversible σ-dimerizations of 9,10-dialkoxyanthracene radical cations, confirmed by crystal and solution studies.
Area of Science:
- Organic Chemistry
- Supramolecular Chemistry
- Photochemistry
Background:
- Anthracene derivatives are known for their unique photophysical properties.
- Radical cations are reactive species often involved in electron transfer processes.
- Dimerization can alter the electronic and optical properties of aromatic systems.
Purpose of the Study:
- To investigate the reversible σ-dimerization of 9,10-dialkoxyanthracene radical cations.
- To characterize the properties and stability of these radical cations and their dimers.
- To provide evidence for reversible dimerization in persistent radical cations of aromatic systems.
Main Methods:
- Synthesis and characterization of 9,10-dialkoxyanthracene derivatives.
- Generation and spectroscopic analysis of radical cations (e.g., UV-Vis, EPR).
- Crystallographic studies of the dimerized dication species.
Main Results:
- Well-defined reversible σ-dimerizations of 9,10-dialkoxyanthracene radical cations were achieved.
- Yellow crystalline σ-dimerized dications dissociated into purple solutions of monomeric radical cations.
- The identity and stability of the radical cations were unequivocally confirmed.
Conclusions:
- Reversible σ-dimerizations of persistent radical cations are feasible in aromatic systems.
- This work demonstrates a novel class of reversible dimerization reactions.
- The findings contribute to understanding the behavior of radical cations in solution and solid states.
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