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Updated: May 12, 2026
09:33
Determination of the Photoisomerization Quantum Yield of a Hydrazone Photoswitch
Published on: February 7, 2022
Molecular photoswitches based on spiro-acridans
Alina Raskosova1, Reinhard Stösser, Werner Abraham
1Humboldt-Universität zu Berlin, Institute for Chemistry, Brook-Taylor-Str. 2, D-12489 Berlin, Germany.
Chemical Communications (Cambridge, England)
|April 4, 2013
Summary
New thermally reversible photochromic spiro-acridans were synthesized, showing high ring opening efficiencies. Their zwitterions, lacking a merocyanine structure, result in millisecond to second lifetimes, with side reactions preventable via substitution.
Area of Science:
- Organic Chemistry
- Materials Science
- Photochemistry
Background:
- Photochromic compounds change color upon light exposure.
- Spiro compounds are known for their unique structural properties.
- Thermally reversible photochromism allows color change reversal with heat.
Purpose of the Study:
- To synthesize novel thermally reversible photochromic spiro-acridans for the first time.
- To investigate the photochromic properties and stability of these new compounds.
- To understand the factors influencing the lifetime of the photoinduced species.
Main Methods:
- Synthesis of spiro-acridan derivatives.
- Photochromic performance evaluation under UV irradiation.
- Spectroscopic analysis to characterize the photoinduced species.
- Kinetic studies to determine the lifetime of the colored form.
Main Results:
- Successful synthesis of thermally reversible photochromic spiro-acridans.
- Demonstrated high ring-opening efficiencies upon photoirradiation.
- The photoinduced zwitterions, lacking a merocyanine structure, exhibited lifetimes ranging from milliseconds to seconds.
- Identified a side reaction that can be suppressed through appropriate substitution.
Conclusions:
- The newly synthesized spiro-acridans represent a novel class of photochromic materials.
- Their tunable lifetimes and high efficiencies make them promising for applications in optical data storage and smart windows.
- Strategic substitution can control reactivity and enhance the stability of the photochromic system.
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