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[Intramolecular cyclization reaction of multiple bonds and its application]
1Division of Pharmaceutical Sciences, Graduate School of Natural Science and Technology, Kanazawa University, Kanazawa, Japan. finagaki@p.kanazawa-u.ac.jp
Yakugaku Zasshi : Journal of the Pharmaceutical Society of Japan
|October 4, 2011
Summary
New methods for synthesizing ring systems use allenes for efficient cycloaddition and cycloisomerization reactions. These strategies enable the construction of complex molecules, including natural products.
Area of Science:
- Organic Chemistry
- Synthetic Chemistry
Context:
- Cycloaddition and cycloisomerization reactions are fundamental in organic synthesis.
- Allenes offer unique reactivity compared to alkenes and alkynes.
- Construction of medium-sized rings remains a synthetic challenge.
Purpose:
- To develop novel cycloaddition and cycloisomerization reactions utilizing allene functionality.
- To explore the efficiency of allene-based methods for constructing monocyclic and bicyclic ring systems.
- To apply these methods in the asymmetric synthesis of natural products.
Summary:
- Developed efficient cycloaddition and cycloisomerization reactions involving allenes with alkynes, alkenes, or other allenes.
- These methods leverage the dual reactivity of allenes, facilitating the construction of diverse monocyclic and bicyclic structures.
- Successfully synthesized medium-sized rings with high efficiency.
- Achieved asymmetric formal synthesis of (+)-nakadomarin A and total synthesis of (+)-fawcettimine and (+)-lycoposerramine-B via stereoselective Pauson-Khand reactions.
Impact:
- Provides versatile synthetic routes for complex ring systems.
- Highlights the utility of allenes as valuable building blocks in organic synthesis.
- Demonstrates the power of these methods in natural product synthesis, advancing stereoselective synthesis strategies.
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