Biomimetic tail-to-head terpene cyclizations using the resorcin[4]arene capsule catalyst
Ivan Cornu1, Leonidas-Dimitrios Syntrivanis1, Konrad Tiefenbacher2,3
1Department of Chemistry, University of Basel, Basel, Switzerland.
Nature Protocols
|December 1, 2023
Summary
Researchers developed a biomimetic protocol for tail-to-head terpene (THT) cyclizations using a resorcin[4]arene capsule as an artificial enzyme mimic. This method enables the synthetic access to complex terpene natural products previously difficult to obtain.
Area of Science:
- Organic Chemistry
- Biochemistry
- Catalysis
Background:
- Tail-to-head terpene (THT) cyclization is vital for generating diverse natural product skeletons.
- Synthetic THT cyclizations are challenging without enzymatic assistance.
Purpose of the Study:
- To develop a synthetic protocol for biomimetic THT cyclizations using a capsule catalyst.
- To enable efficient synthesis of complex terpene natural products.
Main Methods:
- Utilized a hexameric resorcin[4]arene capsule as an artificial enzyme mimic.
- Employed HCl as a co-catalyst for THT cyclizations and carbocationic rearrangements.
- Optimized reaction parameters including water content, HCl concentration, temperature, and solvent.
Main Results:
- Successfully synthesized two terpenes, isolongifolene and presilphiperfolan-1β-ol, using the capsule catalysis.
- Demonstrated the methodology's versatility by varying water content for different synthetic outcomes.
- Validated the reaction setup with a commercially available substrate, nerol.
Conclusions:
- The developed protocol provides a detailed procedure for biomimetic THT cyclizations.
- This capsule-catalysis methodology offers a novel approach for synthesizing complex terpene natural products.
- The protocol is adaptable and facilitates access to valuable chemical scaffolds.
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