Tetrakis ethylene chemiluminescence

Freeman T.F., Seitz W.R., Oxygen probe based on tetrakis(alkylamino)ethylene chemiluminescence. Anal. Chem. 1981 53 98. 

Me Capra in particular proposed n> that the chemiluminescence reactions of a large number of organic compounds had this concerted dioxetane decomposition step as key reaction in the production of electronically excited products, namely acridinium salts 25,26,27) indolylperoxides 28>, activated oxalic esters 29>, diphenyl carbene 30>, tetrakis-dimethylamino-ethylene 31 32>, lucigenin 33>, and substituted imidazoles 23>. 

Figure 7 Chemiluminescent reaction of tetrakis(dimethylamino) ethylene (TDE).

This compound chemiluminesces when exposed to air or oxygen. Its CL was first demonstrated by Fletcher and Heller [47, 48] and suggested to occur via formation of a dioxetane by addition of oxygen across the ethylenic double bond. Cleavage of the dioxetane to form excited tetramethylurea results in excitation of the tetrakis (dimethylamino) ethylene, whose CL is in good agreement with the fluorescence spectrum of the parent compound. The reaction has been used for the analysis of oxygen [49, 50],... 

When oxygen is removed from a reaction solution of tetrakis-(dimethylamino)ethylene (TMAE), the chemiluminescence decays slowly enough to permit rate studies. The decay rate constant is pseudo-first-order and depends upon TMAE and 1-octanol concentrations. The kinetics of decay fit the mechanism proposed earlier for the steady-state reaction. The elementary rate constant for the dimerization of TMAE with TMAE2+ is obtained. This dimerization catalyzes the decomposition of the autoxidation intermediate. 

VITThen tetrakis(dimethylamino)ethylene (TMAE) is autoxidized, it chemiluminesces with the reaction catalyzed by proton donors (12). The 1-octanol-catalyzed reaction has been studied in detail at 30°C. (2, 3, 8). The over-all oxidation (11) can be written as the sum of two reactions ... 

The chemiluminescent autoxidation of tetrakis(dimethylamino)-ethylene (35) is spectacular.62 Ground-state oxygen is sufficiently reactive to produce the dioxetane laq, presumably via electron transfer, radical cage coupling, and cyclization [Eq. (22)]. Besides tetramethyl-... 

Selectivity of chemiluminescence reactions can be a concern. Some reactions are essentially compound-specific. An example is tetrakis(dime-thylamino)ethylene, which undergoes chemiluminescence reaction only with Oz- Although such specificity provides freedom from measurement interference, that chemiluminescence reaction then lacks universal application. In other cases, several species could yield emission with a given reagent. These situations then require coupling of the chemiluminescence detection with some sort of highly selective physical or chemical step (such as chromatography, immunoassay, enzyme reactions) to achieve an interference-free measurement. An... 

Apart from the tetrakis dialkylamino-ethylenes, the only other compounds which have been reported to be spontaneously chemiluminescent in air, are certain thioesters [5]. In contrast, the tetrakis alkylthio-ethylenes are not luminescent [6]. Sulphuric acid is the only product to be identified in what is evidently a gas phase reaction. The light intensity is roughly in proportion to the volatility of the esters (9-11). Although the report is sufficiently detailed as to describe the formation of luminescent smoke rings, attempts to reproduce the phenomenon have not been successful [7]. 

This can be achieved by chemiluminescent smokes [139,140], aerosols and sprays [141-143], or emulsions in water [144] - all of them containing tetrakis-dialky lamino ethylenes. 

---