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On the Stability of Cyclophane Derivates Using a Molecular Fragmentation Method
Oinam Romesh Meitei1, Andreas Heßelmann1
1Lehrstuhl für Theoretische Chemie, Universität Erlangen-Nürnberg, Egerlandstr. 3, D-91058, Erlangen, Germany.
Chemphyschem : a European Journal of Chemical Physics and Physical Chemistry
|September 23, 2016
Summary
This study introduces a molecular fragmentation method to analyze cyclophane stability. Increased conjugation in paracyclophane systems reduces repulsive intramolecular interactions, enhancing overall molecular stability.
Area of Science:
- Computational chemistry
- Molecular modeling
- Physical organic chemistry
Background:
- Cyclophanes are cyclic organic compounds known for their unique structural properties.
- Understanding the factors influencing cyclophane stability is crucial for designing novel materials and catalysts.
- Previous studies have explored cyclophane stability through various experimental and theoretical approaches.
Purpose of the Study:
- To investigate the stability of cyclophane derivatives using a novel molecular fragmentation method.
- To decompose molecular energy into strain and intramolecular interaction energies.
- To analyze the nature of intramolecular interactions in systematically varied paracyclophane systems.
Main Methods:
- Application of a molecular fragmentation method to calculate molecular strain and intramolecular interaction energies.
- Utilizing the random-phase approximation (RPA) and its extensions.
- Employing density functional theory (DFT) methods with dispersion corrections.
Main Results:
- Molecular strain energies calculated by the fragmentation method show good agreement with experimental data.
- Intramolecular interaction energies in the studied cyclophanes are found to be repulsive.
- Increasing conjugation in doubled layered paracyclophane systems reduces repulsive interactions and enhances stability.
Conclusions:
- The molecular fragmentation method provides accurate insights into cyclophane stability.
- Repulsive intramolecular interactions play a significant role in cyclophane stability.
- Systematic structural modifications, such as increased conjugation, can be used to tune cyclophane stability.
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