Hexafluoro-2-butyne

Hexafluoro-2-butyne
Skeletal formula of hexafluoro-2-butyne
Ball-and-stick model of hexafluorobut-2-yne
Names
Preferred IUPAC name
1,1,1,4,4,4-Hexafluorobut-2-yne
Other names
HFB
Identifiers
3D model (JSmol)
ChemSpider
ECHA InfoCard 100.010.667 Edit this at Wikidata
EC Number
  • 211-732-7
RTECS number
  • ES0702500
  • InChI=1S/C4F6/c5-3(6,7)1-2-4(8,9)10 checkY
    Key: WBCLXFIDEDJGCC-UHFFFAOYSA-N checkY
  • InChI=1/C4F6/c5-3(6,7)1-2-4(8,9)10
    Key: WBCLXFIDEDJGCC-UHFFFAOYAY
  • FC(F)(F)C#CC(F)(F)F
Properties
C4F6
Molar mass 162.034 g·mol−1
Appearance Colorless gas
Density 1.602 g/cm3
Melting point −117 °C (−179 °F; 156 K)
Boiling point −25 °C (−13 °F; 248 K)
Insoluble
Structure
0 D
Hazards[1]
Occupational safety and health (OHS/OSH):
Main hazards
 Toxic gas
GHS labelling:
GHS06: Toxic
Danger
H331
P261, P311, P410+P403
Related compounds
Related compounds
 Dimethyl acetylenedicarboxylate
Hexachlorobutadiene
Acetylene
Except where otherwise noted, data are given for materials in their standard state (at 25 °C [77 °F], 100 kPa).
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Hexafluoro-2-butyne (HFB) is a fluorocarbon with the chemical structure CF3C≡CCF3. HFB is a particularly electrophilic acetylene derivative, and hence a potent dienophile for Diels–Alder reactions.[2][3]

Synthesis and reactions

HFB is prepared by the action of sulfur tetrafluoride on acetylenedicarboxylic acid or by the reaction of potassium fluoride (KF) with hexachlorobutadiene.

It reacts with sulfur to give 3,4-bis(trifluoromethyl)-1,2-dithiete.

Cycloaddition of HFB and dithionitronium (NS2+) gives the 1,2,5-dithiazolium cation. This derivative can be reduced to the 7 electron neutral radical. This particular 1,3,5-dithiazole is also rare example of a radical that can be obtained as solid, liquid, and gaseous states. As a gas, it is blue.[4]

References

  1. ^ "Hexafluoro-2-butyne 99%". Sigma-Aldrich.
  2. ^ Essers, Michael; Haufe, Günter (2006). "Hexafluoro-2-butyne". Encyclopedia of Reagents for Organic Synthesis. doi:10.1002/047084289X.rn00669. ISBN 0471936235.
  3. ^ E S Turbanova, A A Petrov (1991). "Perfluoroalkyl(aryl)acetylenes". Russian Chemical Reviews. 60 (5): 501–523. Bibcode:1991RuCRv..60..501T. doi:10.1070/RC1991v060n05ABEH001092.
  4. ^ Brownridge, Scott; Du, Hongbin; Fairhurst, Shirley A.; Haddon, Robert C.; Oberhammer, Heinz; Parsons, Simon; Passmore, Jack; Schriver, Melbourne J.; Sutcliffe, Leslie H.; Westwood, Nicholas P. C. (2000). "The Isolation, Characterisation, Gas Phase Electron Diffraction and Crystal Structure of the Thermally Stable Radical CF3CSNSCCF3". Journal of the Chemical Society, Dalton Transactions (19): 3365–3382. doi:10.1039/B001489N.