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Isolating Free Carbenes, their Mixed Dimers and Organic Radicals
Published on: April 19, 2019
Hybrid super electron donors - preparation and reactivity
Jean Garnier1, Douglas W Thomson, Shengze Zhou
1WestCHEM, Department of Pure and Applied Chemistry, University of Strathclyde, 295 Cathedral Street, Glasgow G1 1XL, United Kingdom.
Beilstein Journal of Organic Chemistry
|September 29, 2012
Summary
New neutral organic electron donors, including pyridinylidene-imidazolylidene systems, efficiently convert iodoarenes to aryl radicals or anions at room temperature. These novel super electron donors show promise for organic synthesis applications.
Area of Science:
- Organic Chemistry
- Electron Transfer Reactions
- Radical Chemistry
Background:
- Development of efficient organic electron donors is crucial for synthetic transformations.
- Existing methods for aryl radical or anion generation often require harsh conditions.
Purpose of the Study:
- To report novel neutral organic electron donors with pyridinylidene-imidazolylidene, pyridinylidene-benzimidazolylidene, and imidazolylidene-benzimidazolylidene linkages.
- To investigate the ability of these donors to convert iodoarenes to aryl radicals and anions at room temperature.
- To explore the influence of base on these electron-transfer reactions.
Main Methods:
- Synthesis of novel neutral organic electron donors.
- Room temperature reactions of iodoarenes with the synthesized donors.
- Analysis of reaction products to confirm aryl radical and anion formation.
- Investigation of the effect of sodium hydride base concentration.
Main Results:
- Pyridinylidene-benzimidazolylidene and imidazolylidene-benzimidazolylidene systems function as the first super electron donors for aryl radical formation from iodoarenes at room temperature.
- The pyridinylidene-imidazolylidene donor efficiently converts iodoarenes to aryl anions under specific conditions.
- Excess sodium hydride base demonstrated a significant and selective effect on certain electron-transfer reactions.
Conclusions:
- Novel neutral organic electron donors have been successfully synthesized and characterized.
- These donors enable efficient generation of aryl radicals and anions from iodoarenes at room temperature, offering a milder alternative to existing methods.
- The study provides insights into the mechanism and selectivity of these electron-transfer processes, including the role of base.
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