Efficient nucleophilic aromatic substitution between aryl nitrofluorides and alkynes
Patrick L DeRoy1, Simon Surprenant, Megan Bertrand-Laperle
1Department of Chemistry, Boehringer Ingelheim (Canada) Ltd, Research and Development, 2100 Cunard Street, Laval, Quebec, Canada.
Organic Letters
|June 8, 2007
Summary
Sodium bis(trimethylsilyl)amide efficiently promotes nucleophilic aromatic substitution reactions. This method yields 2-ethynylnitrobenzene products under mild conditions with good results.
Area of Science:
- Organic Chemistry
- Synthetic Chemistry
Background:
- Nucleophilic aromatic substitution (SNAr) is a fundamental reaction in organic synthesis.
- Electron-deficient aryl fluorides are important substrates in SNAr reactions.
- Efficient methods for coupling aryl fluorides with alkynes are highly sought after.
Purpose of the Study:
- To develop an efficient method for the synthesis of 2-ethynylnitrobenzene derivatives.
- To investigate the use of sodium bis(trimethylsilyl)amide as a base in SNAr reactions.
Main Methods:
- Reaction of electron-deficient aryl fluorides with terminal alkynes.
- Utilizing sodium bis(trimethylsilyl)amide as the base.
- Optimization of reaction conditions for mildness and efficiency.
Main Results:
- The reaction proceeds efficiently, yielding 2-ethynylnitrobenzene products.
- Moderate to excellent yields were obtained.
- The reaction was effective under mild conditions.
Conclusions:
- Sodium bis(trimethylsilyl)amide is an effective base for promoting SNAr reactions between aryl fluorides and terminal alkynes.
- This method provides a facile route to 2-ethynylnitrobenzene derivatives.
- The reaction conditions are mild and the yields are good, making it a valuable synthetic tool.
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