A Scalable Stereoselective Synthesis of Polysubstituted Housanes
Valentin V Veselinov1, Ayan Dasgupta1, Andreas Pielmeier1
1Chemistry Research Laboratory, Department of Chemistry, University of Oxford, 12 Mansfield Road, Oxford, OX1 3TA, U.K.
Organic Letters
|June 4, 2026
Summary
Researchers developed a new method to create diverse bicyclo[2.1.0]pentanes (housanes), valuable in medicinal chemistry. This approach allows for precise functionalization, expanding access to complex, enantioenriched housane scaffolds.
Area of Science:
- Organic Chemistry
- Medicinal Chemistry
- Synthetic Chemistry
Background:
- Small ring bicyclic carbocycles offer unique structural and physicochemical properties for drug discovery.
- Bicyclo[2.1.0]pentanes (housanes) are underutilized due to limited synthetic diversification methods.
- Late-stage functionalization of strained ring systems remains a synthetic challenge.
Purpose of the Study:
- To develop novel methods for the late-stage diversification of bicyclo[2.1.0]pentanes.
- To explore the potential of housanes as isosteres for ortho-substituted benzene rings.
- To enable access to enantioenriched polysubstituted housane scaffolds.
Main Methods:
- Directed metalation for sequential bridgehead and cyclopropane bridge functionalization.
- Computational and X-ray crystallographic analysis to study housane structure-activity relationships.
- Stereospecific boron-mediated 1,2-metalate rearrangement for cyclopentaneboronic ester synthesis.
- Enantioselective synthesis of substituted housanes.
Main Results:
- A straightforward directed metalation approach for di- and trisubstituted housanes with high regio- and diastereoselectivity.
- Demonstration of housanes as viable isosteres for ortho-substituted benzene rings.
- Synthesis of a highly substituted cyclopentaneboronic ester via a novel rearrangement.
- Establishment of an enantioselective route to complex housane derivatives.
Conclusions:
- The developed directed metalation strategy significantly expands the synthetic utility of bicyclo[2.1.0]pentanes.
- Housanes represent promising scaffolds for medicinal chemistry applications.
- The new synthetic methods provide access to valuable, enantioenriched polysubstituted housane building blocks.
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