Strain-ring construction enabled by boronate complex/1,2-metalate rearrangement.
Kanak Kanti Das1, Sutapa Dey2,3
1Universität des Saarlandes, Institut für Organische Chemie, D-66123, Saarbrücken, Germany. kanakiitkgp@gmail.com.
Chemical Communications (Cambridge, England)
|March 3, 2026
Summary
Boronate complex rearrangement offers a powerful synthetic strategy for constructing strained rings. This method overcomes energetic barriers, enabling the creation of complex carbocycles and heterocycles with high stereocontrol.
Area of Science:
- Synthetic organic chemistry
- Organic synthesis
- Strain-ring construction
Background:
- Forming small, strained ring systems is a significant challenge in organic synthesis.
- 1,2-metalate rearrangement of boronate complexes has become a key strategy to overcome these challenges.
- Carbon substituents on boron exhibit high migratory aptitude, facilitating skeletal reorganization.
Purpose of the Study:
- To review key developments in strain-ring construction using boronate complex/1,2-metalate rearrangement.
- To highlight the versatility of this strategy across various boron frameworks.
- To showcase the application of different activation modes in accessing strained rings.
Main Methods:
- Leveraging the 1,2-metalate rearrangement of boronate complexes.
- Utilizing the migratory aptitude of carbon substituents from boron.
- Combining electrophilic, radical, and metal-mediated activation modes with boron migration.
Main Results:
- Successful construction of strained carbocycles and heterocycles.
- Demonstration of ring contraction via skeletal reorganization.
- Access to strained ring systems with high stereocontrol.
Conclusions:
- Boronate complex/1,2-metalate rearrangement is a powerful and unifying strategy for strain-ring construction.
- This approach effectively overcomes the energetic penalties associated with strained ring formation.
- The methodology provides access to diverse strained carbocycles and heterocycles with excellent stereocontrol.
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