1,2-Dioxetanes thermal decomposition kinetics

In addition to ready thermal decomposition, 1,2-dioxetanes are also rapidly decomposed by transition metals (39), amines, and electron-donor olefins (10). However, these catalytic reactions are not chemiluminescent as determined by the temperature drop kinetic method. 

The kinetics of the thermal decomposition of 1,2-dioxetanes and a-peroxylactones are first order and are usually unimolecular. A variety of experimental methods can be used to monitor the rates. These include direct chemiluminescence of the excited carbonyl product,energy-transfer chemiluminescence of the chemienergized excited carbonyl product to an efficient fluorescer, dioxetane consumption or carbonyl product formation by nmr spectroscopy iodometry of the cyclic... 

A kinetics study has been performed on the aqueous iodine oxidation of the thiolactam (78). The rate of oxidation of (78) was found to be approximately 100 times that of a simple cyclic thioether, and this enhancement was ascribed to transannular anchimeric assistance provided by the nitrogen of the amide group <87JOC258i>. The thermal decomposition of the fused dioxetane (79) has been monitored by chemiluminescence decay, and this has been shown to follow first-order kinetics. The activation parameters have been calculated <83CL431>. Second-order rate constants for the quatemization of octahydro-lfl-azonine (9) and other azacycloalkanes with iodomethane in acetonitrile and methanol have been measured <68CCC1429>. The kinetics of the hydrogen-deuterium... 

Kinetic data for the thermal decomposition of 1,2-dioxetans (209) and (210) indicate a first-order reaction, and the activation parameters suggest a two-step decomposition mechanism via the biradical (211). The analogous... 

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