Perfluoroisobutene (PFIB) is the
perfluorocarbon
Fluorocarbons are chemical compounds with carbon-fluorine bonds. Compounds that contain many C-F bonds often has distinctive properties, e.g., enhanced stability, volatility, and hydrophobicity. Fluorocarbons and their derivatives are commerci ...
counterpart of the hydrocarbon
isobutene
Isobutylene (or 2-methylpropene) is a hydrocarbon with the chemical formula . It is a four-carbon branched alkene (olefin), one of the four isomers of butylene. It is a colorless flammable gas, and is of considerable industrial value.
Producti ...
and has the formula (CF
3)
2C=CF
2. An
alkene
In organic chemistry, an alkene is a hydrocarbon containing a carbon–carbon double bond.
Alkene is often used as synonym of olefin, that is, any hydrocarbon containing one or more double bonds.H. Stephen Stoker (2015): General, Organic, an ...
, it is a colorless gas that is notable as a highly toxic
perfluoroalkene. Few simple alkenes are as toxic.
Safety
Perfluoroisobutene is quite toxic with an LCt = 880 mg⋅min⋅m
−3 (mice).
It is a
Schedule 2 substance of the
Chemical Weapons Convention.
Perfluoroisobutene is highly reactive toward
nucleophiles. It hydrolyzes readily to give the relatively innocuous (CF
3)
2CHCO
2H, which readily decarboxylates to give hexafluoropropane. It forms addition compounds with
thiols
In organic chemistry, a thiol (; ), or thiol derivative, is any organosulfur compound of the form , where R represents an alkyl or other organic substituent. The functional group itself is referred to as either a thiol group or a sulfhydryl grou ...
, and it is this reactivity that may be related to its toxicity.
[
PFIB is a product of ]pyrolysis
The pyrolysis (or devolatilization) process is the thermal decomposition of materials at elevated temperatures, often in an inert atmosphere. It involves a change of chemical composition. The word is coined from the Greek-derived elements ''py ...
of polytetrafluoroethylene (PTFE), one of the substances invoked to explain polymer fume fever __NOTOC__
Polymer fume fever or fluoropolymer fever, also informally called Teflon flu, is an inhalation fever caused by the fumes released when polytetrafluoroethylene (PTFE, known under the trade name Teflon) reaches temperatures of 300 ° ...
.
External links
International Chemical Safety Card 1216
See also
* Phosgene
* Bis(trifluoromethyl) disulfide
References
{{Chemical agents
Perfluorinated compounds
Haloalkenes
Pulmonary agents
Trifluoromethyl compounds