Names | |
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IUPAC name
Hexanedinitrile
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Other names
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Identifiers | |
3D model (Jmol)
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1740005 | |
ChemSpider | |
ECHA InfoCard | 100.003.543 |
EC Number | 203-896-3 |
MeSH | adiponitrile |
PubChem CID
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RTECS number | AV2625000 |
UNII | |
UN number | 2205 |
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Properties | |
C6H8N2 | |
Molar mass | 108.14 g·mol−1 |
Appearance | Colourless liquid |
Density | 951 mg mL−1 |
Melting point | 1 to 3 °C; 34 to 37 °F; 274 to 276 K |
Boiling point | 295.1 °C; 563.1 °F; 568.2 K |
50 g/L (20 °C) | |
Vapor pressure | 300 mPa (at 20 °C) |
Refractive index (nD)
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1.438 |
Thermochemistry | |
Std enthalpy of
formation (ΔfH |
84.5–85.3 kJ mol−1 |
Hazards | |
GHS pictograms | |
GHS signal word | DANGER |
H301, H315, H319, H330, H335 | |
P260, P284, P301+310, P305+351+338, P310 | |
EU classification (DSD)
|
T |
R-phrases | R25, R36/37/38 |
S-phrases | S26, S36, S45 |
NFPA 704 | |
Flash point | 93 °C; 199 °F; 366 K (open cup) |
550 °C (1,022 °F; 823 K) | |
Explosive limits | 1.7–4.99% |
Lethal dose or concentration (LD, LC): | |
LD50 (median dose)
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155 mg kg−1(oral, rat) |
US health exposure limits (NIOSH): | |
PEL (Permissible)
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none |
REL (Recommended)
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TWA 4 ppm (18 mg/m3) |
IDLH (Immediate danger)
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N.D. |
Related compounds | |
Related alkanenitriles
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Glutaronitrile |
Related compounds
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hexanedioic acid hexanedihydrazide hexanedioyl dichloride hexanediamide |
Except where otherwise noted, data are given for materials in their standard state (at 25 °C [77 °F], 100 kPa).
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what is ?) | (|
Infobox references | |
Adiponitrile is the organic compound with the formula (CH2)4(CN)2. This dinitrile, a viscous, colourless liquid, is an important precursor to the polymer nylon-6,6. In 2005, about one billion kilograms were produced annually.
Because of the industrial value of adiponitrile, many methods have been developed for its synthesis. Early industrial routes started from furfural and later by the chlorination of butadiene to give 1,4-dichloro-2-butene, which with sodium cyanide, converts to 3-hexenedinitrile, which in turn can be hydrogenated to adiponitrile:
Adiponitrile has also been produced from adipic acid, by dehydration of the diamide, but this route is rarely employed.
The majority of adiponitrile is prepared by the nickel-catalysed hydrocyanation of butadiene, as discovered at DuPont, pioneered by Drinkard. The net reaction is:
The process involves several stages, the first of which involves monohydrocyanation (addition of one molecule of HCN), affording isomers of pentenenitriles as well as 2- and 3-methylbutenenitriles. These unsaturated nitriles are subsequently isomerized to the 3-and 4-pentenenitriles. In the final stage, these pentenenitriles are subjected to a second hydrocyanation, in an anti-Markovnikov sense, to produce adiponitrile.
Research has shown that the 3-pentenenitrile, formed in the first hydrocyanation, can undergo alkene metathesis to give dicyanobutenes, which are readily hydrogenated as described above.