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Activation parameters and excitation yields of 1,2-dioxetanes of photogenotoxic interest

✍ Scribed by Prof. Dr. Waldemar Adam; Axel Beinhauer; Hermann Hauer; Chantu Saha-Möller

Publisher
John Wiley and Sons
Year
1990
Tongue
English
Weight
459 KB
Volume
332
Category
Article
ISSN
1615-4150

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✦ Synopsis

Abstract

The chemiluminescent decomposition of functionalized 1,2‐dioxetanes was examined in toluene solution. Activation energies were measured by isothermal and nonisothermal kinetic methods. Quantum efficiencies were determined by Stern‐Volmer kinetics, using the fluorescers 9,10‐dibromo‐ and 9,10‐diphenylanthracene for the triplet and singlet excitation yields. The derivatives of 3‐hydroxymethyl‐3,4,4‐trimethyl‐1,2‐dioxetane (1a) have free energies of activation (ΔG^≠^) of ca. 25 kcal/mol, but the ΔG^≠^ values of the annelated benzofuran‐type dioxetanes (5) are ca. 1 kcal/mol lower. There exists a reasonable correlation between the free energies of activation (ΔG^≠^) for the thermal decomposition of the dioxetanes and their triplet excitation flux (E~p~^T^).

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