Acyclic sec. -Peroxy-esters

The mechanism of the chemiluminescent decomposition of secondary peroxy-esters shows similar features [7], in that the loss of the secondary proton allows electron transfer to the activator radical cation. Activators are fluorescent compounds of low ionisation potential. In the example shown below the activator is not consumed, and the products, acetophenone and acetic acid, are formed quantitatively. The unactivated decomposition is very closely related to peroxide decomposition generally, and it is not surprising to find that the quantum yield is very low. 

Addition of a fluorescer, such as the easily oxidised dihydro-dibenzo-[a, c]-phenazine gives a much enhanced light yield and the reaction then has much in common with the mechanism proposed by Linschitz for ZnTPP activated luminescence reactions previously discussed. 

The cleavage of the peroxide bond is thought to be preceded by electron transfer from the fluorescer and then back transfer occurs from the ketyl formed by loss of a proton from the secondary peroxide. 

Some models of the excitation reaction in bacterial bioluminescence seem to require a similar explanation [8]. 

Biochemical studies [9] have resulted in the scheme shown  

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