Thionyl fluoride

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Thionyl fluoride
Ball-and-stick model SOF2.png
Ball-and-stick model
structure Thionyl-fluoride-3D-balls.png
structure
Names
IUPAC name
Thionyl fluoride
Identifiers
3D model (JSmol)
ChemSpider
ECHA InfoCard 100.029.088 OOjs UI icon edit-ltr-progressive.svg
EC Number
  • 231-997-2
PubChem CID
UNII
  • InChI=1S/F2OS/c1-4(2)3 Yes check.svgY
    Key: LSJNBGSOIVSBBR-UHFFFAOYSA-N Yes check.svgY
  • InChI=1/F2OS/c1-4(2)3
    Key: LSJNBGSOIVSBBR-UHFFFAOYAL
  • FS(F)=O
Properties
SOF2
Molar mass 86.06 g·mol−1
Appearancecolorless gas
Melting point −110.5 °C (−166.9 °F; 162.7 K)
Boiling point −43.8 °C (−46.8 °F; 229.3 K)
hydrolysis
Solubility soluble in ethanol, ether, benzene
Vapor pressure 75.7 kPa (-50 °C) [1]
Structure
trigonal pyramidal
Thermochemistry [2] [ better source needed ]
Std molar
entropy
(S298)
278.6 J/(mol·K)
−715 kJ/mol
56.8 J/(mol·K)
Hazards
GHS labelling:
GHS-pictogram-acid.svg GHS-pictogram-skull.svg
Danger
H300, H310, H314, H330
P260, P262, P264, P270, P271, P280, P284, P301+P310, P301+P330+P331, P302+P350, P303+P361+P353, P304+P340, P305+P351+P338, P310, P320, P321, P322, P330, P361, P363, P403+P233, P405, P501
Related compounds
Related oxohalides
Thionyl chloride
Thionyl bromide
Related compounds
Thiothionyl fluoride
Nitrosyl fluoride
Carbonyl fluoride
Except where otherwise noted, data are given for materials in their standard state (at 25 °C [77 °F], 100 kPa).
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Thionyl fluoride is the inorganic compound with the formula S O F 2. This colourless gas is mainly of theoretical interest, but it is a product of the degradation of sulfur hexafluoride, an insulator in electrical equipment. The molecule adopts a distorted pyramidal structure, with Cs symmetry. The S-O and S-F distances are 1.42 and 1.58 Å, respectively. The O-S-F and F-S-F angles are 106.2 and 92.2°, respectively. [3] [ page needed ]

Contents

Synthesis and reactions

Thionyl fluoride can be produced by the reaction of thionyl chloride with fluoride sources such as antimony trifluoride. [4] [3] :542

3 SOCl2 + 2 SbF3 → 3 SOF2 + 2 SbCl3

Alternatively, it arises via the fluorination of sulfur dioxide: [3] :542

SO2 + PF5 → SOF2 + POF3

Thionyl fluoride arises as a fleeting intermediate from the decomposition of sulfur hexafluoride as the result of electrical discharges which generate sulfur tetrafluoride. SF4 hydrolyzes to give thionyl fluoride, which in turn hydrolyzes further as described below. [5]

As expected from the behavior of the other thionyl halides, this compound hydrolyzes readily, giving hydrogen fluoride and sulfur dioxide: [3] :542

SOF2 + H2O → 2 HF + SO2

In contrast to thionyl chloride and bromide, thionyl fluoride is not useful for halogenation. The related derivative, sulfur tetrafluoride is however useful for that purpose.[ citation needed ]

References

  1. Thionyl fluoride in Linstrom, Peter J.; Mallard, William G. (eds.); NIST Chemistry WebBook, NIST Standard Reference Database Number 69, National Institute of Standards and Technology, Gaithersburg (MD) (retrieved 2014-05-11)
  2. "Thionyl Fluoride". chemister.ru database.
  3. 1 2 3 4 Holleman, A.F. (2001). Holleman, A.F.; Wiberg, Egon; Wiberg, Nils (eds.). Inorganic Chemistry (1st ed.). San Diego, CA: Academic Press. ISBN   0-12-352651-5.
  4. Smith, W. C.; Muetterties, E. L.; Park, J. D.; Settine, Robert (January 1960). "Thionyl Fluoride". Inorganic Syntheses. Vol. 6. pp. 162–163. doi:10.1002/9780470132371.ch50. ISBN   978-0-470-13165-7.
  5. Pepi, Federico; Andreina Ricci; Marco Di Stefano; Marzio Rosi; Giuseppe D'Arcangelo (September 18, 2002). "Thionyl Fluoride from Sulfur Hexafluoride Corona Discharge Decomposition: Gas-Phase Chemistry of (SOF2)H+ Ions". Journal of Physical Chemistry A. 106 (40): 9261–9266. Bibcode:2002JPCA..106.9261P. doi:10.1021/jp021074v.