MgI2-Mediated Solvent-Controlled Divergent Ring-Opening Cyclization/Addition of Spirocyclopropyl Indanediones
Ting Yang1, Ze-Gang Ma2, Wen-Hui Zhang1
1College of Pharmacy, Guizhou University of Traditional Chinese Medicine, Guiyang 550025, P. R. China.
The Journal of Organic Chemistry
|November 17, 2025
Summary
Magnesium iodide (MgI2) enables divergent synthesis of indanedione derivatives through controlled reactions. This method efficiently produces spirocyclopentyl indandiones and 2,2-disubstituted indanediones using different solvents.
Area of Science:
- Organic Chemistry
- Synthetic Chemistry
- Catalysis
Background:
- Indanediones are valuable scaffolds in medicinal chemistry.
- Developing efficient and selective synthetic routes to substituted indanediones is crucial.
Purpose of the Study:
- To develop a novel, solvent-controlled divergent synthesis of indanedione derivatives.
- To explore the utility of magnesium iodide (MgI2) as a catalyst in cycloaddition and Michael addition reactions.
Main Methods:
- Formal (3 + 2) cycloaddition reactions mediated by MgI2 in tetrahydrofuran.
- Ring-opening iodination-Michael addition reactions mediated by MgI2 in toluene.
- Utilized spirocyclopropyl indanediones and nitroalkenes as starting materials.
- Employed high-resolution mass spectrometry for mechanistic studies.
Main Results:
- Achieved efficient synthesis of spirocyclopentyl indandiones with up to 95% yield and >20:1 diastereomeric ratio (dr).
- Successfully synthesized 2,2-disubstituted indanediones with up to 68% yield.
- Demonstrated solvent-controlled divergent synthesis based on reaction conditions.
Conclusions:
- The developed MgI2-mediated protocol offers an efficient pathway for divergent synthesis of complex indanedione structures.
- The study provides insights into a plausible reaction mechanism based on experimental evidence.
- This method expands the synthetic toolbox for accessing diverse indanedione derivatives.
![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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