Optimizing the lifetimes of phenoxonium cations derived from vitamin E via structural modifications
Yanni Yue1, Maria L Novianti, Malcolm E Tessensohn
1Division of Chemistry and Biological Chemistry, School of Physical and Mathematical Sciences, Nanyang Technological University, Singapore 637371, Singapore. webster@ntu.edu.sg.
Organic & Biomolecular Chemistry
|October 21, 2015
Summary
New sterically hindered phenolic compounds, similar to vitamin E, form stable phenoxonium diamagnetic cations upon oxidation. These cations resist hydrolysis, with their reactivity studied using cyclic voltammetry and digital simulation in acetonitrile solutions.
Area of Science:
- Organic Chemistry
- Electrochemistry
- Physical Chemistry
Background:
- Vitamin E analogs are crucial antioxidants.
- Phenolic compounds are widely studied for their chemical properties.
- Understanding the stability and reactivity of oxidized phenolic species is important.
Purpose of the Study:
- To synthesize novel sterically hindered phenolic compounds.
- To investigate the electrochemical oxidation of these compounds.
- To characterize the resulting phenoxonium ions and their reactivity towards hydrolysis.
Main Methods:
- Systematic synthesis of new phenolic compounds.
- Electrochemical oxidation in acetonitrile using a -2e(-)/-H(+) process.
- Cyclic voltammetry with controlled water addition.
- Digital simulation for data modeling.
Main Results:
- Identification of sterically hindered phenolic compounds.
- Formation of diamagnetic phenoxonium cations resistant to hydrolysis.
- Quantification of phenoxonium ion reactivity in the presence of water.
Conclusions:
- Sterically hindered phenoxonium diamagnetic cations exhibit significant stability against hydrolysis.
- Electrochemical methods coupled with simulation provide insights into the reactivity of these transient species.
- The findings contribute to the understanding of phenolic compound electrochemistry and stability.
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