Acetonitrile
From Wikipedia, the free encyclopedia
| Acetonitrile | |
|---|---|
 |
 |
| IUPAC name | Ethanenitrile |
| Other names | Methyl cyanide; cyanomethane |
| Identifiers | |
| CAS number | [75-05-8] |
| RTECS number | AL7700000 |
| SMILES | CC#N |
| InChI | 1/C2H3N/c1-2-3/h1H3 |
| Properties | |
| Molecular formula | C2H3N |
| Molar mass | 41.05 g/mol |
| Appearance | colorless liquid |
| Density | 0.786 g/mL liquid |
| Melting point |
-45 °C |
| Boiling point |
82 °C |
| Solubility in water | miscible |
| Solubility | organic solvents |
| Acidity (pKa) | 25 |
| Hazards | |
| MSDS | External MSDS |
| EU classification | Flammable, harmful |
| NFPA 704 |
 3
2
0
|
| R-phrases | R11, R20/21/22, R36 |
| S-phrases | (S1/2), S16, S36/37 |
| Flash point | 2 °C |
| Related compounds | |
| Related nitriles | propionitrile, butyronitrile |
| Related compounds | acetic acid, acetamide, ethylamine |
| Supplementary data page | |
| Structure and properties |
n, εr, etc. |
| Thermodynamic data |
Phase behaviour Solid, liquid, gas |
| Spectral data | UV, IR, NMR, MS |
| Except where noted otherwise, data are given for materials in their standard state (at 25 °C, 100 kPa) Infobox disclaimer and references |
|
Acetonitrile (ACN) is the chemical compound with formula CH3CN. This colourless liquid is the simplest organic nitrile and is widely used as a solvent.
Contents |
[edit] Production
Acetonitrile is a by-product from the manufacture of acrylonitrile.[1] Production trends for acetonitrile thus generally follow those of acrylonitrile. Acetonitrile may also be produced by reacting carbon monoxide, ammonia, and hydrogen gases.[2] The four main producers of acetonitrile in the United States are: INEOS, DuPont, J.T. Baker Chemical, and Sterling Chemicals. In 1992, 32.3 million pounds (14,700 t) of acetonitrile were produced in the United States of America.
[edit] Applications
[edit] Solvent
Acetonitrile is used as a solvent in the purification of butadiene. Being relatively non-toxic, it is sometimes used in formulations for nail polish remover, as are acetone and ethyl acetate. In more specialized applications, it is a common solvent of choice for testing an unknown chemical reaction. It is polar ((3.84 D) with a convenient liquid range. It dissolves a wide range of compounds without complications due to its low acidity. For this reason, it is widely used as a mobile phase in HPLC. Similarly, it is a popular solvent in cyclic voltammetry because of its relatively high dielectric constant. The properties of acetone are similar, but it is more reactive toward bases and nucleophiles.
[edit] Organic synthesis
Acetonitrile is a two-carbon building block in organic synthesis[3] as in the production of pesticides to perfumes. Its reaction with cyanogen chloride affords malononitrile.
[edit] Ligand in inorganic chemistry
In inorganic chemistry, acetonitrile is widely employed as a displaceable ligand. A good example is the use of PdCl2(MeCN)2, prepared by heating a suspension of (polymeric) palladium chloride in acetonitrile:
- [PdCl2]n + 2n MeCN → n PdCl2(MeCN)2
[edit] Safety
Acetonitrile has a modest toxicity, the LD50 for rats being 3.8 g/kg. Unlike the behavior of other nitriles, the metabolism of acetonitrile does not release cyanide.[1] According the MSDS "Acetonitrile is metabolized to cyanide. Patients with significant exposures should be observed for signs of cyanide poisoning and treated accordingly."
[edit] References
- ^ a b Peter Pollak, Gérard Romeder, Ferdinand Hagedorn, Heinz-Peter Gelbke "Nitriles" in Ullmann's Encyclopedia of Industrial Chemistry, Wiley-VCH, 2002: Weinheim. DOI: 10.1002/14356007.a17_363
- ^ US patent 4179462, "Process for preparing acetonitrile", granted [[]], assigned to Monsanto
- ^ DiBiase, S. A.; Beadle, J. R.; Gokel, G. W.. "Synthesis of α,β-Unsaturated Nitriles from Acetonitrile: Cyclohexylideneacetonitrile and Cinnamonitrile". Org. Synth.; Coll. Vol. 7: 108.
