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Substituent Effects on Transient, Carbodiimide-Induced Geometry Changes in Diphenic Acids
Isuru M Jayalath1, Madelyn M Gerken1, Georgia Mantel1
1Department of Chemistry & Biochemistry, Miami University, Oxford, Ohio 45056, United States.
The Journal of Organic Chemistry
|August 19, 2021
Summary
Chemically fueled molecular clamps change geometry via carbodiimide-induced anhydride formation. This system allows for the study of structure-property relationships in diphenic acid derivatives.
Area of Science:
- Chemical Biology
- Supramolecular Chemistry
Background:
- Motor proteins undergo nucleotide-induced conformational changes crucial for cellular functions.
- Diphenic acids are versatile molecular building blocks.
Purpose of the Study:
- To develop a chemically fueled system mimicking biological conformational changes.
- To investigate carbodiimide-induced geometry changes in substituted diphenic acids.
Main Methods:
- Utilized carbodiimide chemistry to form transient diphenic anhydrides.
- Studied the kinetics of anhydride formation and decay.
- Analyzed structure-property relationships based on substituent effects.
Main Results:
- Achieved a molecular clamp system with reduced twist about the biaryl bond.
- Established a kinetic model to determine system characteristics like yield and lifetime.
- Demonstrated that steric hindrance is tolerated, but electronic effects significantly impact performance.
Conclusions:
- Transient diphenic anhydrides offer a tunable platform for molecular geometry control.
- Electronic properties of substituents are critical for optimizing system efficiency and stability.
- Provides design principles for functional systems using diphenic acid units.
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