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Oligothiophene-linked bisnaphthopyrans: sequential and temperature-dependent photochromism
1Laboratorium für Organische Chemie, ETH Zürich, HCI H335, 8093 Zürich, Switzerland.
Chemistry (Weinheim an Der Bergstrasse, Germany)
|December 23, 2006
Summary
New photochromic bisnaphthopyrans featuring oligothiophene linkers exhibit sequential and temperature-controlled photochromism. The bithiophene linker specifically enhances colorability and coloration quantum yield in these advanced photochromic materials.
Area of Science:
- Materials Science
- Organic Chemistry
- Photochemistry
Background:
- Photochromic compounds undergo reversible color changes upon light exposure.
- Bisnaphthopyrans are a class of photochromic molecules with potential applications.
- Oligothiophenes are conjugated systems known for their electronic properties.
Purpose of the Study:
- Synthesize novel photochromic bisnaphthopyrans linked with oligothiophenes.
- Investigate the photochromic behavior, including sequential and temperature-dependent effects.
- Analyze the influence of linker length and substituents on photochromic properties.
Main Methods:
- Chemical synthesis of bisnaphthopyran-oligothiophene conjugates.
- Spectroscopic analysis to study photochromic transitions.
- Kinetic studies of photo- and thermal-induced processes.
Main Results:
- Successful synthesis of photochromic bisnaphthopyrans linked by oligothiophenes.
- Observed sequential and temperature-dependent photochromism.
- Demonstrated linker length-dependent cross-talk between photochromophores.
- Bithiophene linkers resulted in high colorability and quantum yield.
Conclusions:
- Oligothiophene linkers significantly modulate the photochromic properties of bisnaphthopyrans.
- The length of the oligothiophene linker controls the interaction between photochromic units.
- Bisnaphthopyrans with bithiophene linkers show promising performance for photochromic applications.
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