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Published on: July 17, 2020
Photochemistry of anthracene-9,10-endoperoxide
Henk Fidder1, Alexandra Lauer, Wolfgang Freyer
1Institut für Physik, Freie Universität Berlin, Arnimallee 14, D-14195 Berlin, Germany. hendrik.fidder@fu-berlin.de
The Journal of Physical Chemistry. A
|May 14, 2009
Summary
The photochemistry of anthracene-9,10-endoperoxide (APO) was studied using UV-Vis spectroscopy. Anthracene and a diepoxide were primary products, with secondary products forming from APO and its photoproducts.
Area of Science:
- Photochemistry
- Organic Chemistry
- Spectroscopy
Background:
- Anthracene-9,10-endoperoxide (APO) is a key intermediate in photochemical reactions.
- Understanding APO photochemistry is crucial for synthetic applications and reaction mechanism elucidation.
Purpose of the Study:
- To quantitatively investigate the wavelength dependence of APO photochemistry in acetonitrile.
- To identify primary and secondary photoproducts and their formation pathways.
- To determine the total photochemistry quantum yield across a range of excitation wavelengths.
Main Methods:
- UV-Vis spectroscopy was used to study APO photochemistry.
- Reactions were conducted in acetonitrile at 5 degrees C.
- Excitation wavelengths ranged from 240 to 450 nm.
- Photoproducts were identified and quantified.
Main Results:
- Anthracene (AC) and a diepoxide (DE) were identified as primary photoproducts.
- DE dominated at short exposure times, while AC formed for wavelengths <= 320 nm, with a maximum quantum yield of 29% at 270 nm.
- Anthraquinone (AQ) and a bicyclic acetal (BA) were secondary products formed from both DE and ground-state APO.
- Total photochemistry quantum yield was near unity for wavelengths <= 310 nm and decreased monotonically from 300 to 450 nm.
Conclusions:
- APO exhibits complex photochemistry dependent on excitation wavelength.
- Both primary and secondary photoproducts play roles in the overall reaction pathway.
- The quantum yield is high for shorter wavelengths, indicating efficient photochemical transformation.
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