Propionitrile, also known as ethyl cyanide and propanenitrile, is an organic compound with the formula CH3CH2CN. It is a simple aliphatic nitrile. The compound is a colourless, water-soluble liquid. It is used as a solvent and a precursor to other organic compounds.[7]
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| Names | |||
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| Preferred IUPAC name Propanenitrile[5] | |||
| Other names | |||
| Identifiers | |||
3D model (JSmol) | |||
| 773680 | |||
| ChEBI | |||
| ChEMBL | |||
| ChemSpider | |||
| ECHA InfoCard | 100.003.151 | ||
| EC Number |
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| MeSH | propionitrile | ||
PubChem CID | |||
| RTECS number |
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| UNII | |||
| UN number | 2404 | ||
CompTox Dashboard (EPA) | |||
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| Properties | |||
| C3H5N | |||
| Molar mass | 55.080 g·mol−1 | ||
| Appearance | Colourless liquid | ||
| Odor | Sweetish, pleasant, ethereal[6] | ||
| Density | 772 mg mL−1 | ||
| Melting point | −100 to −86 °C; −148 to −123 °F; 173 to 187 K | ||
| Boiling point | 96 to 98 °C; 205 to 208 °F; 369 to 371 K | ||
| 11.9% (20 °C)[6] | |||
| log P | 0.176 | ||
| Vapor pressure | 270 μmol Pa−1 kg−1 | ||
| -38.5·10−6 cm3/mol | |||
Refractive index (nD) | 1.366 | ||
| Thermochemistry | |||
Heat capacity (C) | 105.3 J K−1 mol−1 | ||
Std molar entropy (S⦵298) | 189.33 J K−1 mol−1 | ||
Std enthalpy of formation (ΔfH⦵298) | 15.5 kJ mol−1 | ||
Std enthalpy of combustion (ΔcH⦵298) | −1.94884–−1.94776 MJ mol−1 | ||
| Hazards | |||
| GHS labelling: | |||
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| Danger | |||
| H225, H300, H310, H319, H332 | |||
| P210, P264, P280, P301+P310, P302+P350, P305+P351+P338 | |||
| NFPA 704 (fire diamond) | |||
| Flash point | 6 °C (43 °F; 279 K) | ||
| Explosive limits | 3.1%-?[6] | ||
| Lethal dose or concentration (LD, LC): | |||
LD50 (median dose) | 39 mg kg−1 (oral, rat) | ||
| NIOSH (US health exposure limits): | |||
PEL (Permissible) | none[6] | ||
REL (Recommended) | TWA 6 ppm (14 mg/m3)[6] | ||
IDLH (Immediate danger) | N.D.[6] | ||
| Related compounds | |||
Related alkanenitriles | |||
Related compounds | DBNPA | ||
Except where otherwise noted, data are given for materials in their standard state (at 25 °C [77 °F], 100 kPa). | |||
Production
The main industrial route to this nitrile is the hydrogenation of acrylonitrile. It is also prepared by the ammoxidation of propanol (propionaldehyde can also be used instead):[7]
- CH3CH2CH2OH + O2 + NH3 → CH3CH2CN + 3 H2O
Propionitrile is a byproduct of the electrodimerisation of acrylonitrile to adiponitrile.
In the laboratory propanenitrile can also be produced by the dehydration of propionamide, by catalytic reduction of acrylonitrile, or by distilling ethyl sulfate and potassium cyanide.
Applications
Propionitrile is a solvent similar to acetonitrile but with a slightly higher boiling point. It is a precursor to propylamines by hydrogenation. It is a C-3 building block in the preparation of the drug flopropione by the Houben-Hoesch reaction.
The nitrile aldol reaction with benzophenone, followed by reduction of the nitrile with lithium aluminium hydride gives 2-MDP. This agent possesses appetite suppressant and antidepressant properties.
Chemical structure of 2-MDP
Safety
The toxicity LD50 of propionitrile is listed as 39 mg/kg[8] and as 230 my (both rats, oral).[7]
In 1979, the Kalama (Vega) plant in Beaufort, South Carolina experienced an explosion during the production of propionitrile by nickel-catalyzed hydrogenation of acrylonitrile.[9] This site is now one of the two Superfund cleanup sites in South Carolina.[9]