What Are Nitriles Definition Structure Preparation Methods Reactions and Applications
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 in Organic Chemistry Structure Preparation and Properties
1. What is a nitrile in organic chemistry?
A nitrile is an organic compound that contains the functional group –C≡N, known as the cyano group. In nitriles, the carbon of the cyano group is triple-bonded to nitrogen and bonded to an alkyl or aryl group.
- General formula: R–C≡N
- Functional group name: cyano group
- Example: CH3CN (ethanenitrile or acetonitrile)
2. What is the general formula of nitriles?
The general formula of simple aliphatic nitriles is CnH2n-1N. This formula applies to open-chain (acyclic) nitriles derived from alkanes.
- Functional group: –C≡N
- Structure: R–C≡N
- Example (n = 2): C2H3N (ethanenitrile)
3. How are nitriles prepared in the laboratory?
Nitriles are commonly prepared by nucleophilic substitution of alkyl halides with cyanide ions. The reaction involves heating a haloalkane with alcoholic potassium cyanide.
- Reagent: KCN or NaCN
- Solvent: alcoholic medium
- Reaction type: nucleophilic substitution (SN2)
CH3Br + KCN → CH3CN + KBr
This method increases the carbon chain length by one carbon atom.
4. What happens when nitriles undergo hydrolysis?
On hydrolysis, a nitrile is converted into a carboxylic acid or its salt. The reaction occurs under acidic or basic conditions with heating.
- Acidic hydrolysis (complete):
R–C≡N + 2H2O + HCl → R–COOH + NH4Cl - Basic hydrolysis (followed by acidification):
R–C≡N + 2H2O + NaOH → R–COONa + NH3
5. What is the difference between nitriles and isonitriles?
The key difference is that nitriles have the structure R–C≡N, while isonitriles have the structure R–N≡C. In nitriles, the carbon is bonded to the alkyl group, whereas in isonitriles, nitrogen is bonded to the alkyl group.
- Nitrile functional group: –C≡N
- Isonitrile functional group: –N≡C
- Nitriles are generally less foul-smelling than isonitriles
6. How are nitriles reduced to amines?
Nitriles are reduced to primary amines by catalytic hydrogenation or strong reducing agents. The triple bond is hydrogenated to form an –CH2NH2 group.
- Catalytic hydrogenation:
R–C≡N + 2H2(g) → R–CH2NH2 (Ni or Pt catalyst) - Chemical reduction: LiAlH4 in dry ether
7. Why are nitriles considered polar compounds?
Nitriles are polar because the C≡N bond has a large electronegativity difference, creating a strong dipole moment. Nitrogen is more electronegative than carbon, pulling electron density toward itself.
- Bond type: polar covalent triple bond
- Results in high dipole moment
- Leads to relatively high boiling points compared to similar alkanes
8. What is an example of a common nitrile and its uses?
A common nitrile is acetonitrile (CH3CN), widely used as a polar aprotic solvent. It is colorless and has a relatively high dielectric constant.
- Used in high-performance liquid chromatography (HPLC)
- Solvent for organic reactions
- Intermediate in pharmaceutical and agrochemical synthesis
9. How do you name nitriles according to IUPAC rules?
According to IUPAC nomenclature, nitriles are named by adding the suffix –nitrile to the parent alkane name. The carbon of the –C≡N group is counted as part of the main chain.
- CH3CN → ethanenitrile
- C2H5CN → propanenitrile
- Benzene–C≡N → benzonitrile
10. What are the physical properties of nitriles?
Nitriles generally have moderate to high boiling points and are polar, colorless liquids or solids. Their properties are influenced by the polar –C≡N group.
- Higher boiling points than alkanes of similar molar mass
- Lower members are soluble in water
- Have a characteristic mild odor (except isonitriles, which are foul-smelling)
