Chemiluminescence from reactions of bis(pentachloro-phenyl)oxalate, hydrogen peroxide and fluorescent compounds. Role of the fluor and nature of chemielectronic process(es)

Abstract

The effect of fluorescence activators on the quantum yields and emission decay rates of the chemiluminescence arising from the reaction between bis(pentachlorophenyl)oxalate and hydrogen peroxide has been examined in detail. Chemiluminescence was detected for a range of fluors with excited-singlet-state energies <400 kJ mol^–1. The chemiluminescence quantum yields were strongly dependent upon the nature and concentrations of the fluorescent activators, but the chemiluminescence decay rates were independent of the properties of the fluor. Delayed addition of the fluor had no effect upon both chemiluminescence quantum yields and decays.

A quantitative relationship has been shown to exist between the normalised chemiluminescence quantum yields (ϕ_CL/ϕ_F) and the half-wave oxidation potential of the fluorescence activators. The results are discussed in terms of chemically initiated electron transfer between a reactive intermediate and the fluorescence activators. A mechanism involving 3-pentachlorophenoxy-3-hydroxy-1,2-dioxetanone as an intermediate is proposed.