The endoperoxide of tetrabenzopentancene. A new photochromic endoperoxide
- The thermal and the photochemical reactions of the endoperoxide of Tetrabenzo(bc,fg.lm,pq)- pentacene have been investigated with respect to its photochromic properties. The thermal yield of irreversible rearrangement reactions was determined to be Adec = 0.045. From the activation parameters of the thermal cycloreversion. forming the parent hydrocarbon and oxygen, a half life time of 114 years at 20 °C has been extrapolated. For the quantum yield of the irreversible photochemical rearrangement a value of Qdec = 0.03 was obtained. As can be seen from the wavelength dependence of the photocycloreversion quantum yield Q1, cycloreversion occurs not only from the thermalized S2(πccπ*cc) but from higher excited states too. The maximum quantum yield was found at 302 nm to be (Q1 = 0.15. From our results it follows that this endoperoxide is of high quality in respect to the colour change colourless/blue and to thermal stability, whereas the reversibility is only moderate.
Author: | Reinhard Schmidt |
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URN: | urn:nbn:de:hebis:30:3-743223 |
DOI: | https://doi.org/10.1515/zna-1984-1015 |
ISSN: | 1865-7109 |
Parent Title (German): | Zeitschrift für Naturforschung, A |
Publisher: | Verlag der Zeitschrift für Naturforschung |
Place of publication: | Tübingen |
Document Type: | Article |
Language: | English |
Date of Publication (online): | 2014/06/02 |
Year of first Publication: | 1984 |
Publishing Institution: | Universitätsbibliothek Johann Christian Senckenberg |
Release Date: | 2023/06/27 |
Volume: | 39 |
Issue: | 10 |
Page Number: | 5 |
First Page: | 998 |
Last Page: | 1002 |
HeBIS-PPN: | 510764258 |
Institutes: | Biochemie, Chemie und Pharmazie / Biochemie und Chemie |
Dewey Decimal Classification: | 5 Naturwissenschaften und Mathematik / 54 Chemie / 540 Chemie und zugeordnete Wissenschaften |
Sammlungen: | Universitätspublikationen |
Licence (German): | ![]() |