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| Names | |||
|---|---|---|---|
| Preferred IUPAC name 1,1,3,3,3-Pentafluoro-2-(trifluoromethyl)prop-1-ene | |||
| Other names Perfluoroisobutene, Perfluoroisobutylene, Octafluoroisobutylene, Octafluoro-sec-butene, PFIB | |||
| Identifiers | |||
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3D model (JSmol) | |||
| ChEMBL | |||
| ChemSpider |
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| ECHA InfoCard | 100.108.743 | ||
| EC Number |
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| RTECS number |
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| UNII | |||
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| Properties | |||
| C4F8 | |||
| Molar mass | 200.030 g/mol | ||
| Appearance | colorless gas | ||
| Density | 8.2 g/l | ||
| Melting point | −130 °C (−202 °F; 143 K) | ||
| Boiling point | 7.0 °C (44.6 °F; 280.1 K) | ||
| Hazards | |||
| GHS labelling: | |||
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| Danger | |||
| H330,H370 | |||
| P260,P264,P270,P271,P284,P304+P340,P307+P311,P310,P320,P321,P403+P233,P405,P501 | |||
Except where otherwise noted, data are given for materials in theirstandard state (at 25 °C [77 °F], 100 kPa). | |||
Perfluoroisobutene (PFIB) is theperfluorocarbon with the formula(CF3)2C=CF2. Classified as a perfluoroalkene, it is the fluorinated counterpart of the hydrocarbonisobutene. This colorless gas is notable for its high toxicity.[1]
PFIB is one product ofpyrolysis ofpolytetrafluoroethylene (PTFE).[2] Tetrafluoroethylene thermallydimerizes tooctafluorocyclobutane, which above 600 °C degrades tohexafluoropropylene and PFIB.[1]
Perfluoroisobutene is highly reactive towardnucleophiles, e.g. methanol.[1] It also forms addition compounds withthiols, and it is this reactivity that may be related to its toxicity.[3] It hydrolyzes readily to give the relatively innocuous (CF3)2CHCO2H, which readily decarboxylates to givehexafluoropropane.[citation needed]
Oxidation of HFIB withpotassium permanganate giveshexafluoroacetone.[4]
Perfluoroisobutene is highly toxic with an LCt = 880 mg⋅min⋅m−3 (mice).[3] It is aSchedule 2 substance of theChemical Weapons Convention. Its toxicity is comparable to that ofphosgene.[1]
