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Polyalkynylanthracenes--syntheses, structures and their behaviour towards UV irradiation
Jan-Hendrik Lamm1, Johanna Glatthor, Jan-Henrik Weddeling
1Universität Bielefeld, Fakultät für Chemie, Lehrstuhl für Anorganische Chemie und Strukturchemie, Centrum für Molekulare Materialien CM2, Universitätsstraße 25, D-33615 Bielefeld, Germany. mitzel@uni-bielefeld.de.
Organic & Biomolecular Chemistry
|August 28, 2014
Summary
New anthracene compounds with trimethylsilyl-protected ethynyl groups were synthesized. One derivative undergoes reversible photodimerization upon UV exposure, offering potential in materials science.
Area of Science:
- Organic Chemistry
- Materials Science
Background:
- Anthracene derivatives are known for their photophysical properties.
- Functionalization of anthracene with ethynyl groups can tune its electronic and structural characteristics.
Purpose of the Study:
- To synthesize novel bis- and tris[(trimethylsilyl)ethynyl]anthracenes.
- To investigate the photochemical behavior of these derivatives, particularly photodimerization.
- To explore the potential of these compounds as building blocks in cross-coupling reactions.
Main Methods:
- Multistep synthesis involving cross-coupling reactions.
- Nuclear Magnetic Resonance (NMR) spectroscopy, including variable temperature (VT) NMR, to study photochemical reactions and thermal reversibility.
- High-resolution mass spectrometry and X-ray diffraction for compound characterization.
Main Results:
- Successful synthesis of various bis- and tris[(trimethylsilyl)ethynyl]anthracenes.
- Observation of photodimerization in 9,10-bis[(trimethylsilyl)ethynyl]anthracene upon UV irradiation, which is thermally reversible.
- Conversion of deprotected diethynylanthracenes to SnMe3-functionalized alkynes.
Conclusions:
- The synthesized ethynylanthracenes exhibit interesting photochemical properties, including reversible photodimerization.
- The SnMe3-functionalized alkynes are potential building blocks for constructing highly conjugated systems via Stille cross-coupling reactions.
- The study expands the scope of functionalized anthracenes for advanced materials applications.
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