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Published on: February 7, 2017
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Conformationally Controlled Linear and Helical Hydrocarbons Bearing Extended Side Chains
Lin Guo1, Oliver J Dutton1, Murat Kucukdisli1
1School of Chemistry, University of Bristol, BS8 1TS, Bristol, U.K.
Journal of the American Chemical Society
|September 30, 2021
Summary
Flexible hydrocarbon chains with controlled conformations are crucial for medicine and materials. New substitution patterns allow large groups on linear or helical chains, enabling precise molecular design for applications like drug targeting.
Area of Science:
- Organic Chemistry
- Supramolecular Chemistry
- Materials Science
Background:
- Conformationally controlled flexible molecules are vital for applications where molecular shape and adaptability are key.
- Hydrocarbon chain conformation is typically governed by avoiding syn-pentane interactions, leading to linear (syn-anti) or helical (all-syn) structures.
- Incorporating large substituents often leads to unavoidable syn-pentane interactions, hindering conformational control.
Purpose of the Study:
- To identify substitution patterns that enable the incorporation of large groups onto conformationally controlled hydrocarbon chains.
- To design flexible molecules with predictable linear or helical conformations for specific applications.
- To overcome limitations in conformational control imposed by bulky substituents in flexible chains.
Main Methods:
- Computational analysis to predict conformational behavior.
- Chemical synthesis of novel hydrocarbon derivatives.
- Nuclear Magnetic Resonance (NMR) spectroscopy for structural and conformational analysis.
Main Results:
- Achieved near-linear conformations (95%) in syn-anti hydrocarbons with acetoxyethyl side chains by adopting nonideal eclipsed conformations.
- Demonstrated that maintaining helical conformations in all-syn hydrocarbons requires strategic removal of adjacent methyl groups.
- Successfully incorporated large substituents onto linear and helical hydrocarbon backbones while preserving conformational integrity.
Conclusions:
- Developed strategies to design conformationally controlled flexible hydrocarbon chains with large substituents.
- Enabled the precise orientation of functional groups for applications in multivalent binding and cooperative reactivity.
- Paved the way for designing molecules targeting protein-protein interactions in disease-relevant contexts.
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