Anthracene-resorcin[4]arene-based capsules: synthesis and photoswitchable features
Sebastian Bringmann1, Ralf Brodbeck, Ramona Hartmann
1Bielefeld University, Department of Chemistry, Organic Chemistry I, Universitätsstraße 25, 33615, Bielefeld, Germany.
Organic & Biomolecular Chemistry
|September 20, 2011
Summary
Researchers synthesized novel hemicarcerands with anthracene units. Only one compound (11) reopened upon 300 nm irradiation, unlike related structures, highlighting specific photochemical responses in these complex molecules.
Area of Science:
- Supramolecular Chemistry
- Photochemistry
- Organic Synthesis
Background:
- Hemicarcerands are molecular capsules with unique host-guest properties.
- Anthracene derivatives are known for their photochemical reactivity, including dimerization.
- Understanding the photochemical behavior of complex molecules is crucial for developing new materials and applications.
Purpose of the Study:
- To synthesize novel hemicarcerands incorporating photoactive anthracene units.
- To investigate the photochemical behavior and dimerization modes of these new compounds.
- To determine the conditions required for the photoinduced opening of the hemicarcerand cages.
Main Methods:
- Synthesis of novel hemicarcerand derivatives.
- Nuclear Magnetic Resonance (NMR) spectroscopy for structural elucidation.
- Photochemical irradiation studies using UV-Vis spectroscopy and specific wavelengths (e.g., 300 nm).
Main Results:
- Several new hemicarcerands with anthracene units were successfully synthesized.
- NMR studies confirmed a 9,10-9',10'-dimerization mode for compounds 9 and 11, typical of anthracene.
- Only compound 11 exhibited photoinduced reopening upon irradiation at 300 nm; compounds 9 and 10 did not reopen under tested conditions (heating or irradiation).
Conclusions:
- The photochemical behavior of hemicarcerands is influenced by their specific structure and the incorporated photoactive units.
- Selective photoinduced opening was achieved for a specific hemicarcerand derivative (compound 11).
- Further research is needed to understand the factors preventing the reopening of compounds 9 and 10.
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