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Ethylene Polymerizations Using Parallel Pressure Reactors and a Kinetic Analysis of Chain Transfer Polymerization
Published on: November 27, 2015
Electron-transfer reactions with significant changes in structure. Unsymmetrical crowded ethylenes
Norma A Macías-Ruvalcaba1, Dennis H Evans
1Department of Chemistry, University of Arizona, Tucson, Arizona 85721, USA.
The Journal of Physical Chemistry. B
|December 1, 2006
Summary
Electrochemical reduction mechanisms of four anthrone derivatives were studied. Structural changes during reduction vary, with some compounds exhibiting folded-to-twisted transformations and others showing minimal structural changes.
Area of Science:
- Electrochemistry
- Organic Chemistry
- Physical Chemistry
Background:
- Anthrone derivatives are complex organic molecules with unique structural properties.
- Understanding their electrochemical behavior is crucial for various applications in materials science and organic electronics.
Purpose of the Study:
- To elucidate the electrochemical reduction mechanisms of xanthylideneanthrone (6), thioxanthylideneanthrone (7), 10-(diphenylmethylene)anthrone (8), and 9-(diphenylmethylene)-9H-fluorene (9).
- To investigate the relationship between molecular structure and electrochemical reduction pathways in these compounds.
Main Methods:
- Electrochemical reduction studies were performed using dimethylformamide as the solvent.
- Analysis involved observing structural changes from neutral to charged states (anion radical, dianion).
Main Results:
- Compounds 6 and 7 showed reduction from folded neutral forms to twisted anion radical forms via a square scheme.
- Compound 8's reduction data aligned with the same square scheme, though a concerted one-step reduction was also possible.
- Compound 9, lacking a foldable fluorene system, existed in twisted forms throughout reduction and underwent two reversible steps, with the second complicated by dianion instability.
Conclusions:
- The electrochemical reduction pathways are significantly influenced by the initial molecular conformation and the ability of the ring system to undergo structural changes.
- Compound 9's rigid structure leads to a different reduction mechanism compared to the more flexible anthrone derivatives.
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