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Preparation of Contiguous Bisaziridines for Regioselective Ring-Opening Reactions
Published on: July 28, 2022
An Evans-Tishchenko-ring-closing metathesis approach to medium-ring lactones
Jennifer I Aird1, Alison N Hulme, John W White
1School of Chemistry, The University of Edinburgh, West Mains Road, Edinburgh EH9 3JJ, UK.
Organic Letters
|January 30, 2007
Summary
Researchers developed a new synthesis for medium-ring lactones using sequential Evans-Tishchenko and ring-closing metathesis reactions. This method achieves high diastereoselectivity and yields, demonstrating its utility in complex molecule synthesis.
Area of Science:
- Organic Chemistry
- Synthetic Chemistry
- Lactone Synthesis
Background:
- Medium-ring lactones are important structural motifs in natural products.
- Efficient synthetic routes to these compounds are highly sought after.
- Existing methods may lack efficiency or stereocontrol.
Purpose of the Study:
- To develop a novel and efficient synthetic strategy for medium-ring lactones.
- To achieve high diastereoselectivity and yields in the synthesis.
- To demonstrate the applicability of the method in synthesizing complex natural products.
Main Methods:
- Sequential application of the Evans-Tishchenko reaction and ring-closing metathesis (RCM).
- Optimization of reaction conditions for both steps.
- Synthesis of unsaturated aldehydes and beta-hydroxy ketones as precursors.
Main Results:
- High diastereoselectivity (>95:5) achieved in the Evans-Tishchenko reaction.
- Optimized RCM conditions provided high yields of medium-ring lactones.
- The synthetic sequence was successfully applied to construct the core of octalactin A.
Conclusions:
- The combined Evans-Tishchenko and RCM approach offers a powerful new route to medium-ring lactones.
- This strategy provides excellent stereocontrol and efficiency.
- The method is viable for the synthesis of complex, functionalized lactones.
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