Triiodine fluorosulfate

Triiodine fluorosulfate
Names
	Other names Iodine fluorosulfate iodide; Triiodine fluorosulfonate;
Identifiers
CAS Number	13537-36-5;
3D model (JSmol)	Interactive image;
	InChI InChI=1S/FHO3S.I3/c1-5(2,3)4;1-3-2/h(H,2,3,4);/q;+1/p-1 Key: GBXBCNLVCWGHPO-UHFFFAOYSA-M;
	SMILES O=S(=O)([O-])F.I[I+]I;
Properties
Chemical formula	FI3O3S
Molar mass	479.77 g·mol−1
Appearance	brown solid
Density	1.7844 g/cm3
Melting point	92 °C (198 °F; 365 K)
	Except where otherwise noted, data are given for materials in their standard state (at 25 °C [77 °F], 100 kPa). Infobox references

Triiodine fluorosulfate is the inorganic compound with the chemical formula I₃SO₃F. It is the fluorosulfate (SO₃F⁻) salt of the I+3 polyhalogen ion.^[2]

Synthesis

Triiodine fluorosulfonate is obtained from iodine and iodine(I) fluorosulfonate at 85 °C.^[3]

I₂ + ISO₃F → I₃SO₃F

Also, a reaction of iodine with peroxydisulfuryl difluoride:^[2]^[4]

3I₂ + S₂O₆F₂ → 2I₃SO₃F

The compound hydrolyzes well in water and dissolves in sulfuric acid.

It reacts with tetrafluoroethylene (C₂F₄) to form ICF₂CF₂O₃SF and I₂.^[5]

^ Williamson, Stanley M. (1966). Recent Progress in Sulfur-Fluorine Chemistry. Progress in Inorganic Chemistry. Vol. 7. John Wiley & Sons, Ltd. pp. 39–81. doi:10.1002/9780470166086.ch2. ISBN 978-0-470-17675-7.
^ ^a ^b U.S. Government Research Reports. U.S. Department of Commerce, Office of Technical Services. 1964. p. 24. Retrieved 18 August 2025.
^ Aubke, Friedhelm; Cady, George H. (1 March 1965). "Iodine Fluorosulfates". Inorganic Chemistry. 4 (3): 269–273. doi:10.1021/ic50025a001. ISSN 0020-1669. Retrieved 18 August 2025.
^ Macintyre, Jane E. (23 July 1992). Dictionary of Inorganic Compounds. CRC Press. p. 3131. ISBN 978-0-412-30120-9. Retrieved 18 August 2025.
^ Fokin, A. V.; Studnev, Yu. N.; Rapkin, A. I.; Tatarinov, A. S. (1 August 1983). "Reaction of iodine fluosulfate and tris(fluosulfate) with haloalkanes". Bulletin of the Academy of Sciences of the USSR, Division of Chemical Science. 32 (8): 1700–1702. doi:10.1007/BF00954296. ISSN 1573-9171.