Formal Cycloadditions Driven by the Homolytic Opening of Strained, Saturated Ring Systems
Alexander S Harmata1, B J Roldan1, Corey R J Stephenson1
1Department of Chemistry, University of Michigan, 930 N University Ave, Ann Arbor, MI 48109-1055, USA.
Angewandte Chemie (International Ed. in English)
|October 14, 2022
Summary
Radical formal cycloadditions are rapidly advancing, driven by new free radical chemistry and the need for complex sp3-rich molecules. These methods offer efficient access to valuable ring systems previously difficult to synthesize.
Area of Science:
- Organic Chemistry
- Synthetic Chemistry
- Catalysis
Background:
- Renewed interest in free radical chemistry and the demand for sp3-rich ring systems are fueling research.
- Photoredox catalysis has significantly advanced free radical chemistry.
- The "Escape from Flatland" concept in medicinal chemistry drives the need for complex 3D molecular architectures.
Purpose of the Study:
- To summarize recent advancements in strain-driven, radical formal cycloaddition reactions.
- To analyze the current state and future directions of this rapidly evolving field.
- To highlight the synthesis of valuable sp3-rich ring systems.
Main Methods:
- Development of radical-mediated formal cycloaddition reactions.
- Exploration of catalytic and asymmetric variants.
- Application to various strained ring systems beyond cyclopropanes.
Main Results:
- Dozens of new radical formal cycloaddition reactions have been reported.
- These methods provide access to functionally decorated sp3-rich molecules.
- Cyclopropanes and other strained ring systems are effectively synthesized.
Conclusions:
- Strain-driven radical formal cycloadditions are a powerful strategy for constructing complex molecular scaffolds.
- The field is dynamic, with ongoing development of novel catalytic and asymmetric methodologies.
- These reactions are crucial for accessing valuable sp3-rich compounds in medicinal chemistry and beyond.
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