Harnessing Molecular Strain to Program 1,2-Migration in Boronic Ester Chemistry
1Kekulé-Institut Für Organische Chemie Und Biochemie, Rheinische Friedrich-Wilhelms-Universität, Bonn, Germany.
Chemistry, an Asian Journal
|June 7, 2026
Summary
Strain energy in small rings drives stereospecific 1,2-metalate rearrangements in boronic ester chemistry. This approach offers a programmable strategy for synthesizing complex molecules with controlled stereochemistry.
Area of Science:
- Organic Chemistry
- Synthetic Chemistry
- Stereochemistry
Background:
- Strain in small-ring systems is an intrinsic driver for chemical reactions.
- Classical electrophilic activation is a common method for promoting rearrangements.
Purpose of the Study:
- To explore the use of stored strain energy in small rings as a driver for stereospecific 1,2-metalate rearrangements.
- To demonstrate a programmable strategy for controlling 1,2-migration in boronic ester chemistry.
Main Methods:
- Embedding strain energy within nitrogen-containing rings, cyclopropanes, epoxides, and bicyclo[1.1.0]butanes.
- Utilizing transition-metal-mediated and metal-free triggers to release strain energy.
- Analyzing the stereospecificity and efficiency of the carbon migration process.
Main Results:
- Strain release lowers activation barriers and enforces concerted pathways for 1,2-migrations.
- Stereochemical information is faithfully transferred from boron to carbon.
- Efficient access to complex, sp3-rich frameworks from simple precursors is achieved.
Conclusions:
- Deliberate exploitation of molecular strain provides a general and programmable strategy for controlling 1,2-migration.
- This approach expands the synthetic toolbox for constructing stereochemically defined molecules.
- Strain-driven rearrangements offer an alternative to classical activation methods in boronic ester chemistry.
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