Oxidation by aqueous fluoroxysulfate: Catalysis by silver(I)

Article abstract of DOI:10.1021/ic50221a035

The oxidations of the ions Cr³⁺, Co²⁺, and VO²⁺ by the fluoroxysulfate ion, SO₄F^-, in aqueous solution are catalyzed by Ag⁺. The rate-determining step for all three catalyzed reactions is the bimolecular oxidation of Ag⁺ by SO₄F^-, which has a rate constant of (1.3 ± 0.2) × 10³ M^-1 s^-1 at 17°C. Activation parameters for this reaction are ΔH^≠ = 6.1 ± 0.5 kcal/mol and ΔS = -23 ± 2 cal/(mol deg). In the absence of Ag⁺, Co²⁺ and VO²⁺ react very slowly with SO₄F^-, while Cr³⁺ does not react at all. Despite its high thermodynamic oxidizing power, the fluoroxysulfate ion acts as a very selective oxidant.