Key Characteristics and Uses of Nitriles in Chemistry
A nitrile is an organic compound which is also known as Cyano Compound. Nitrile definition, in organic chemistry, is a category of organic compounds attached to the atom of carbon. You can represent the Cyano group as (-C=N).
To get a more specific explanation of the question of what is nitrile, let us move ahead and go through the details below:
Acrylonitrile is a compound that is processed in huge quantities. The procedure called ammoxidation is used for processing nitriles. This process is mostly dependent on the state of oxidation of propylene. At that time, there is the availability of a catalyst along with ammonia. The compound further forms a very significant constituent, precisely of polymeric elements. The component of this compound also includes synthetic rubbers, thermoplastic resins and acrylic fibres and textiles apart from polymeric substances.
There are some compounds of a nitrile that are generally produced by simply heating carboxylic acids along with the compounds of ammonia in the presence of certain catalysts. The whole procedure is ideal for preparing nitriles with the use of fats and oils. Further such products are used in the form of softening agents in different substances like textiles, synthetic rubbers and plastics.
You can also use these products for the manufacture of amines. Even amides can be heated along with the compounds of phosphorus pentoxide for forming nitrile compounds. These can even be reduced to certain primary amines simply by the reaction of lithium aluminium hydride or by getting them hydrolysed in the form of carboxylic acids. At the same time, there is the availability of a particular base or an acid.
What is Nitrile Structure and Formula?
This image depicts the structure of
R - C \[\equiv\]N
Nitrile can be defined as an organic chemical containing the Cyano functional subunit or group. Nitrile Structure is CN- where the atoms of nitrogen and carbon have triple bonding or C≡N-. General nitrile formula comes to RCN where R stands for the organic subunit or group.
Understanding the Hydrolysis of Nitriles
The compound nitrile goes through different procedures of reaction. These include reduction, hydrolysis and alkylation. Here we will be getting a clear understanding of all the different varieties of nitrile reactions and specifically the hydrolysis of nitriles. The hydrolysis of nitriles takes place in the availability of a base or an acid.
The procedure generally makes way for or manufactures carboxylic acids and carboxamides most efficiently. Then there is the reduction of nitriles procedure where nitriles are entirely reduced to tertiary or primary amines simply by treating them in the presence of lithium aluminium hydride. There are different catalysts also used for completing the reduction of nitriles procedure.
The next procedure is nitrile alkylation which produces nitrile anions. In all these procedures, nitriles are treated in one way or the other. It leads to the formation of a certain substance in the presence of a base, acid or catalyst. The other nitrile reactions include Friedel-Crafts acylation and nucleophilic addition reaction.
The Physical and Chemical Properties of Nitrile
You can segregate the Nitrile properties into two categories, and they are chemical and physical properties. The properties of nitriles are as follows:
Nitriles come with boiling points that measure between 82 and 118 degree C.
They appear more as colourless liquids and solids with exclusive odours.
Nitriles display high electronegativity and polar.
They also exhibit very strong dipole to dipole shifts.
Nitriles even show the van der Waals dispersion forces between molecules.
Nitriles are water-soluble, but their solubility in water decreases with an increase in the chain length.
When it comes to nitrile melting point, acids, oils, and chemicals can easily break down vinyl and latex gloves. But nitriles come with higher tolerance features to such compounds. It also can resist higher temperature ranges in comparison to latex gloves. Nitrile has the potential of bearing with temperatures ranging between -40 and +180 degree C.
Uses of Nitriles
Nitriles are used in different industrial and medical applications. The varied Nitrile uses are as follows:
The various compounds of nitriles are applicable in the form of antidiabetic drugs. These drugs are suitable for treating breast cancer.
YOu can even use nitriles for manufacturing nitrile seals, gloves and hoses. This is because nitriles are highly resistant to a large number of chemicals.
Pericyazine- a nitrile compound is used in the form of an antipsychotic for the treatment of opiate dependence. This nitrile compound can easily be found in several animal and plant sources.
Nitriles are also ideal for applications in different oil-resistant elements.
They are perfect for situations and settings where work needs to be done at low temperatures.
You can also use nitriles in hydraulic hoses, aircraft systems and automotive systems.
FAQs on Nitriles: Structure, Properties, and Applications
1. What is the general structure of a nitrile functional group?
A nitrile is an organic compound containing a cyano group (-C≡N). The general formula is R-C≡N, where 'R' represents an alkyl or aryl group. The carbon and nitrogen atoms within the cyano group are sp hybridised, which results in a linear geometry with a bond angle of 180°. The characteristic triple bond consists of one sigma (σ) bond and two pi (π) bonds.
2. What are some key physical properties of nitriles?
The key physical properties of nitriles are determined by the polar cyano group:
- Physical State: Lower nitriles are typically colourless liquids with distinct, sometimes almond-like, odours, whereas higher homologues are waxy solids.
- Boiling Point: Nitriles exhibit high boiling points for their molecular mass due to strong dipole-dipole interactions. They lack O-H or N-H bonds, so they cannot form hydrogen bonds with themselves.
- Solubility: Lower-chain nitriles, like acetonitrile, are soluble in water. This is because the lone pair on the nitrogen can form hydrogen bonds with water molecules. As the hydrocarbon chain lengthens, solubility decreases.
- Polarity: The C≡N bond is highly polar, resulting in a large molecular dipole moment.
3. What are the most common applications of nitriles in industry?
Nitriles are versatile compounds with significant industrial applications:
- Synthetic Rubber: Acrylonitrile is a crucial monomer for producing nitrile rubber (Buna-N), which is highly valued for its resistance to oils, fuels, and chemicals, making it ideal for hoses and seals.
- Organic Synthesis: They serve as important intermediates for creating other functional groups, including amines, amides, and carboxylic acids.
- Pharmaceuticals: The cyano group is a key structural component in various medicines and therapeutic agents.
- Super Glue: Cyanoacrylate, a nitrile derivative, is the primary ingredient in super glue adhesives.
4. Why are nitriles considered such versatile building blocks in organic synthesis?
Nitriles are extremely versatile in organic chemistry because the cyano group can be easily converted into three other fundamental functional groups through straightforward reactions:
- Complete Hydrolysis: Reacting a nitrile with an acid or base catalyst and water yields a carboxylic acid (R-COOH).
- Partial Hydrolysis: Under controlled conditions, hydrolysis can be stopped at the intermediate stage to produce an amide (R-CONH₂).
- Reduction: Using reducing agents like LiAlH₄ or catalytic hydrogenation, a nitrile can be reduced to a primary amine (R-CH₂NH₂).
5. How does the structure of a nitrile differ from an isonitrile?
The primary difference between a nitrile and an isonitrile (or isocyanide) lies in the atom to which the organic group (R) is attached:
- In a nitrile (R-C≡N), the organic group is bonded directly to the carbon atom of the cyano group.
- In an isonitrile (R-N⁺≡C⁻), the organic group is bonded to the nitrogen atom.
6. How does the cyano group influence the reactivity of nitriles?
The cyano group (-C≡N) dictates the chemical behaviour of nitriles. Due to the high electronegativity of nitrogen, the carbon atom of the cyano group is electron-deficient and thus electrophilic. This makes it a target for attack by nucleophiles. The lone pair of electrons on the nitrogen atom allows it to act as a weak base. This dual nature allows nitriles to undergo reactions like nucleophilic addition, hydrolysis, and reduction, all centred on the reactive triple bond.
7. Why is acetonitrile (CH₃CN) a commonly used solvent in organic chemistry?
Acetonitrile is a widely used solvent because it is a polar aprotic solvent. This means it has a high dipole moment, allowing it to dissolve many polar and ionic compounds, but it lacks acidic protons (like those in water or alcohols). The absence of acidic protons prevents it from interfering with reactions that involve strong bases or nucleophiles, such as in S_N2 reactions. Its relatively low boiling point also makes it easy to remove from a reaction mixture through evaporation.
