HYPOFLUOROUS ACID

Hypofluorous acid
Hypofluorous acid Hypochlorous acid The dimensions shown above refer to HOF in the gas phase[1]
General
Systematic name	hypofluorous acid
Other names	hydrogen hypofluorite hydrogen fluorate(I) fluoric(I) acid
Molecular formula	HFO
SMILES	HOF
Molar mass	36.0057 g mol−1
Appearance	pale yellow liquid above −117 °C white solid below −117 °C
CAS number	[14034-79-8]
Properties
Density and phase	? g/cm3, ?
Solubility in water	?
Other solvents	?
Melting point	−117 °C (? K)
Boiling point	< 0 °C decomposes at 0 °C
Acidity (p''K''a)
Structure
Dipole moment	? D
Hazards
MSDS	External MSDS
Main hazards	?
NFPA 704
R/S statement	R: ? S: ?
RTECS number	?
Supplementary data page
Structure and properties	''n'', εr, etc.
Thermodynamic data	Phase behaviour Solid, liquid, gas
Spectral data	UV, IR, NMR, MS
Related compounds
Other cations	lithium hypofluorite, LiOF
Related compounds	hypochlorous acid, HOCl
Except where noted otherwise, data are given for materials in their standard state (at 25 °C, 100 kPa)

'Hypofluorous acid' is the chemical compound with the formula HOF. It is an intermediate in the oxidation of water by fluorine, which affords HF and oxygen. It is the only hypohalic acid that can be isolated as a solid. HOF is explosive, decomposing to oxygen and HF^[2].
The compound has been characterized in the solid phase by X-ray crystallography as a bent molecule with an angle of 101°. The O-F and O-H bond lengths are 1.442 and 0.78 A, respectively. The solid framework consists of chains with O-H---O linkages. Note that these solid phase measurements differ somewhat from those observed in the gaseous phase, which are shown in the accompanying illustration.
Hypofluorous acid in acetonitrile (generated ''in situ'' by passing gaseous fluorine through "wet" acetonitrile) serves as a highly electrophilic oxygen-transfer agent.^[3] Treating phenanthroline with this reagent yielded the previously elusive ''1,10-phenanthroline dioxide'',^[4] more than 50 years after the first unsuccessful attempt.^[5]

Contents

See also

References

See also

★ Hypochlorous acid, a related species that is more technologically important but has not been obtained in pure form.

References

1. p. 857
2. W. Poll, G. Pawelke, D. Mootz, E. H. Appelman, “The Crystal Structure of Hypofluorous Acid : Chain Formation by O-H ^{. . .} O Hydrogen Bonds” ''Angewandte Chemie International Edition in English'' '1988', volume ''27'', pp 392-3.
3. S. Rozen, M. Brand, ''Angew. Chem. Int. Ed.'' '1986', ''25'', 554-5; S. Dayan, Y. Bareket, S. Rozen, ''Tetrahedron'' '1999', ''55'', 3657.
4. S. Rozen, S. Dayan, ''Angew. Chem. Int. Ed.'' '1999', ''38'', 3471-3.
5. F. Linsker, R.L. Evans, ''J. Am. Chem. Soc.'' '1946', ''68'', 403.