Sulfur chloride pentafluoride

Sulfur chloride pentafluoride is an inorganic compound with the formula SF
5
Cl
. It exists as a colorless gas at room temperature and is highly toxic, like most inorganic compounds containing the pentafluorosulfide (SF5) functional group.[1] The compound adopts an octahedral geometry with C
4v
symmetry. Sulfur chloride pentafluoride is the only commercially available reagent for adding the SF
5
group to organic compounds.[2][3]

Sulfur chloride pentafluoride
Skeletal formula of sulfur chloride pentafluoride
Ball-and-stick model of the sulfur chloride pentafluoride molecule
Names
Other names
Pentafluorochlorosulfanyl
Identifiers
CAS Number
3D model (JSmol)
ChemSpider
ECHA InfoCard 100.034.014
PubChem CID
CompTox Dashboard (EPA)
Properties
Chemical formula
SClF
5
Molar mass 162.510 g mol−1
Appearance Colorless gas
Density 6.642 g dm−3
Melting point −64 °C (−83 °F; 209 K)
Boiling point −19 °C (−2 °F; 254 K)
Hazards
Main hazards Toxic
Except where otherwise noted, data are given for materials in their standard state (at 25 °C [77 °F], 100 kPa).
N (what is YN ?)
Infobox references

Reactivity

In contrast to the high reactivity and toxicity of SF
5
Cl
, sulfur hexafluoride (SF
6
), is inert and nontoxic despite having a closely related chemical formula. This difference highlights the lability of the S-Cl bond in this molecule.

Under free-radical conditions, SF
5
Cl
adds across double bonds. The following reaction involves the reaction of propene:

CH
3
CHCH
2
+ SF
5
Cl
→ CH3CH(Cl)CH2SF5

The addition reaction is catalyzed by Et
3
B
at around -30 °C. SF
5
Br
is used similarly.[2]

SF
5
Cl
is also a precursor to O(SF5)2 and F2NSF5 (from tetrafluorohydrazine).

Synthesis

Sulfur chloropentafluoride can be synthesized by several routes, starting from two lower sulfur fluorides, sulfur tetrafluoride and disulfur decafluoride:[1]

SF
4
+ Cl
2
+ CsFSF
5
Cl
+ CsCl
ClF + SF
4
SF
5
Cl
S
2
F
10
+ Cl
2
→ 2 SF
5
Cl

The corresponding SF
5
Br
is prepared similarly from in-situ generated bromine monofluoride.[4]

References

  1. Nyman, F., Roberts, H. L., Seaton, T. "Sulfur Chloride Pentafluoride" Inorganic Syntheses, 1966, Volume 8, p. 160. doi:10.1002/9780470132395.ch42
  2. Dolbier, William R.; et al. (2006). "A convenient and efficient method for incorporation of pentafluorosulfanyl (SF5) substituents into aliphatic compounds". Journal of Fluorine Chemistry. 127 (10): 1302–10. doi:10.1016/j.jfluchem.2006.05.003.
  3. Savoie, Paul R.; Welch, John T. (2015). "Preparation and Utility of Organic Pentafluorosulfanyl-Containing Compounds". Chemical Reviews. 115 (2): 1130–1190. doi:10.1021/cr500336u. PMID 25341449.
  4. Winter, Rolf; Terjeson, Robin J.; Gard, Gary L. (1998). "An Improved and Facile Preparation of SF5Br". Journal of Fluorine Chemistry. 89: 105–106. doi:10.1016/S0022-1139(98)00094-3.