Bromyl fluoride and bromosyl trifluoride: preparation and chemical and spectroscopic properties

Abstract

The preparation of bromyl fluoride BrO₂F by several methods is described as well as its reaction with KF to give K[BrF₂O₂]. The Raman spectrum of BrO₂F has been interpreted in terms of a pyramidal structure. The preparation of bromosyl trifluoride BrOF₃ by the reaction of K[BrF₄O] with HF is described together with some of its properties. The ¹⁹F n.m.r. spectrum of molten BrOF₃ and its solutions in SO₂ClF and SO₂F₂ have been recorded and interpreted in terms of fluorine exchange. The Raman spectrum is interpreted on the basis of association in the liquid, solid, and in HF solution. The hydrolysis of BrF₅ and the reactions of BrF₅ with IO₂F, IOF₃, and I₂O₅ produce BrO₂F but not BrOF₃, whereas the reaction of BrF₅ with IO₂F₃ produces a mixture of BrO₂F and BrOF₃. The compound BrO₂F is fluorinated to BrOF₃ and then to BrF₅ by KrF₂, but no bromine(VII) species are formed.