Palladium-Catalyzed Spirocyclization through C-H Activation and Regioselective Alkyne Insertion
Hyung Yoon1, Martin Rölz1, Felicitas Landau1
1Department of Chemistry, Davenport Chemical Laboratories, University of Toronto, 80 St. George Street, Toronto, Ontario, M5S 3H6, Canada.
Angewandte Chemie (International Ed. in English)
|July 15, 2017
Summary
A novel palladium-catalyzed reaction efficiently creates complex spirocyclic compounds like spirooxindoles and spirodihydrobenzofurans. This scalable method offers high yields and excellent regiocontrol for synthesizing valuable molecular architectures.
Area of Science:
- Organic Chemistry
- Catalysis
- Synthetic Methodology
Background:
- Spirocyclic compounds are prevalent in natural products and pharmaceuticals.
- Efficient and regioselective synthesis of spirooxindoles and spirodihydrobenzofurans remains a synthetic challenge.
Purpose of the Study:
- To develop a novel palladium-catalyzed spirocyclization strategy.
- To achieve regioselective synthesis of spirooxindoles and spirodihydrobenzofurans.
Main Methods:
- Palladium-catalyzed reaction sequence.
- Sequential carbopalladation and intramolecular C-H activation.
- Regioselective alkyne insertion.
Main Results:
- Successful synthesis of spirooxindoles and spirodihydrobenzofurans.
- Good to excellent yields achieved for the target spirocyclic products.
- Complete regiocontrol demonstrated in the reaction.
Conclusions:
- A novel and efficient Pd-catalyzed spirocyclization has been established.
- The developed method is readily scalable and provides high regioselectivity.
- This approach offers a valuable tool for accessing complex spirocyclic scaffolds.
![Solid-phase Synthesis of [4.4] Spirocyclic Oximes](/_next/image?url=https%3A%2F%2Fcloudfront.jove.com%2FCDNSource%2Fteasers%2F58508.jpg&w=3840&q=50)
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