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Published on: July 17, 2020
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Porphyrin-Polyyne [3]- and [5]Rotaxanes
Daniel R Kohn1, Levon D Movsisyan1, Amber L Thompson1
1University of Oxford , Department of Chemistry, Chemistry Research Laboratory, Oxford OX1 3TA, United Kingdom.
Organic Letters
|January 6, 2017
Summary
New porphyrin-polyyne rotaxanes were synthesized. These molecules exhibit unique energy transfer properties between their components, paving the way for novel molecular electronic devices.
Area of Science:
- Supramolecular Chemistry
- Organic Synthesis
- Photochemistry
Background:
- Rotaxanes are mechanically interlocked molecules with potential applications in molecular machines and electronics.
- Porphyrins and polyynes are chromophores with distinct photophysical properties.
Purpose of the Study:
- To synthesize novel porphyrin-polyyne rotaxanes.
- To investigate the structural and photophysical properties of these new rotaxane systems.
Main Methods:
- Synthesis of porphyrin-polyyne [3]- and [5]rotaxanes via condensation reactions.
- X-ray crystallography to determine the solid-state structure of a [3]rotaxane.
- Fluorescence spectroscopy to study excited-state energy transfer.
Main Results:
- Successful synthesis of porphyrin-polyyne [3]- and [5]rotaxanes.
- Crystal structure revealed compact macrocycle conformations and intermolecular π-stacked dimers.
- Fluorescence data demonstrated singlet excited-state energy transfer between hexayne, porphyrin, and phenanthroline units.
Conclusions:
- Porphyrin-polyyne rotaxanes possess unique structural features influencing their photophysical behavior.
- Efficient energy transfer pathways were identified within the rotaxane architecture.
- These findings contribute to the design of advanced functional supramolecular materials.
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