Reaction of sulfate and phosphate radicals with α,α,α-trifluorotoluene

Abstract

The aqueous phase reactions of α,α,α-trifluorotoluene (TFT) with sulfate and phosphate radicals have been investigated by conventional flash-photolysis. The bimolecular rate constants obtained for the reactions of SO₄^˙–, H₂PO₄˙, HPO₄^˙– and PO₄˙^2– with TFT are (2 ± 1) × 10⁷, (3.5 ± 0.5) × 10⁷, (2.7 ± 0.5) × 10⁶ and (9 ± 1) × 10⁵M^–1 s^–1, respectively. The organic radicals produced from these reactions exhibit a common absorption peak at 290–300 nm. Additionally, the transients generated from sulfate radicals show a shoulder at 360–370 nm and those generated from phosphate radicals a less intense maximum at 400 nm. Based on the experimental results, the nature of the organic radicals is discussed. Additional information on the hydroxycyclohexadienyl radicals of TFT is obtained from independent experiments with hydrogen peroxide solutions containing TFT.

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