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Boron-Wittig olefination with gem-bis(boryl)alkanes
Ana B Cuenca1, Elena Fernández
1Dept. Organic and Pharmaceutic Chemistry, Institut Químic de Sarrià, Universitat Ramon Llull, Barcelona, Spain.
Chemical Society Reviews
|December 15, 2020
Summary
The boron-Wittig reaction offers a direct route to metalloid-substituted alkenes using boron reagents and carbonyl compounds. This method enables stereoselective synthesis of versatile building blocks for complex organic molecules.
Area of Science:
- Organic Chemistry
- Synthetic Methodology
- Organoboron Chemistry
Background:
- The synthesis of substituted alkenes is crucial in organic chemistry.
- Existing olefination methods may lack stereoselectivity or broad substrate scope.
- Metalloid-substituted alkenes are valuable synthetic intermediates.
Purpose of the Study:
- To provide a tutorial review on the boron-Wittig reaction.
- To systematically present the concept and applications of this olefination.
- To highlight factors influencing stereochemical outcomes.
Main Methods:
- Condensation of lithium α-bis(boryl)carbanions with various carbonyl derivatives (ketones, aldehydes, amides, esters, carboxylic acids).
- Analysis of reaction parameters affecting stereoselectivity.
- Demonstration of applications in target-oriented synthesis.
Main Results:
- The boron-Wittig reaction provides a straightforward method for synthesizing metalloid-substituted alkenes.
- The reaction proceeds with good efficiency and often high stereoselectivity.
- Subsequent C-C bond-forming processes showcase the utility of the generated alkenes.
Conclusions:
- The boron-Wittig reaction is a powerful and versatile tool for alkene synthesis.
- Understanding stereochemical control allows for targeted synthesis of specific alkene isomers.
- This methodology expands the synthetic chemist's toolkit for constructing complex molecules.
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