Acetonitrile (C2N3N): Structure, Uses And Risks

The acetonitrile is a substance of organic origin formed by only carbon, hydrogen and nitrogen. This chemical species belongs to the group of nitriles, with acetonitrile having the simplest structure among those of the organic type.

Nitriles are a class of chemical compounds whose structure is made up of a cyanide group (CN -) and a radical chain (-R). These elements are represented by the following general formula: RC≡N.

It is known that this substance is primarily originated during the production of another species called acrylonitrile (another simple nitrile, with the molecular formula C3H3N, which is used in the manufacture of products in the textile industry) as a by-product of it.

Furthermore, acetonitrile is considered a solvent with medium polarity properties, which is why it is used fairly regularly in RP-HPLC (reverse phase high performance liquid chromatography) analyzes.

As previously mentioned, acetonitrile belongs to the functional group of nitriles, having a molecular formula commonly represented as C2H3N, which can be observed in the structural formula that is exemplified in the figure above.

This image shows a kind of lobe attached to the nitrogen atom, which represents the pair of unpaired electrons that this atom has, and which give it a large part of the reactivity and stability properties that are characteristic of it.

In this way, this species shows a very particular behavior due to its structural arrangement, which translates into weakness to receive hydrogen bonds and little ability to donate electrons.

Among the large number of applications that acetonitrile has, the following can be counted:

1. In a similar way, other species of nitriles, this can go through a process of metabolization in microsomes (vesicular elements that are part of the liver), especially in this organ, to produce hydrocyanic acid.

2. It is widely used as a mobile phase in the type of analysis called reverse phase high performance liquid chromatography (RP-HPLC); that is, as an eluting substance that has high stability, great eluting power and low viscosity.

3. In the case of industrial scale applications, this chemical compound is used in crude oil refineries as a solvent in certain processes, such as the purification of the alkene called butadiene.

4. It is also used as a ligand (a chemical species that combines with an atom of a metallic element, considered to be central in the given molecule, to form a compound or coordination complex) in a large number of nitrile compounds with metals from the group of transition.

5. Similarly, it is used in organic synthesis for a large number of such advantageous chemicals as α-naphthalene acetic acid, thiamine or acetamidine hydrochloride.

The risks associated with exposure to acetonitrile are diverse. Among these is a decreased toxicity when the exposure is for a reduced period of time and in low amounts, being metabolized for the production of hydrocyanic acid.

Likewise, rarely have there been cases of people who have been intoxicated with this chemical species, being poisoned by the cyanide present in the molecule after having been in contact with acetonitrile in different degrees (when inhaled, ingested or absorbed through the skin).

For this reason, the consequences of its toxicity are delayed because the body does not easily metabolize this substance into cyanide, since it takes two to twelve hours for this to occur.