Amines are organic compounds and functional groups that contain a lone pair of electrons on a basic nitrogen atom. Amines are ammonia derivatives in which one or more hydrogen atoms are replaced with an alkyl or aryl group. Aniline, amino acids, and biogenic amines are all vital amines.
A nitrogen atom is connected to a carbonyl carbon atom in the amide functional group. The molecule is a simple amide if the two remaining bonds on the nitrogen atom are connected to hydrogen atoms. A substituted amides is formed when one or both of the remaining bonds on the atom are linked to aryl/alkyl groups.
Amine is a chemical substance generated from ammonia (NH3). In other terms, we can state that amines are ammonia derivatives. An amine is a functional group with a lone pair on a nitrogen atom. Amines are structurally similar to ammonia in that nitrogen can link up to three hydrogen atoms. It also has several features that are related to carbon linkage.
- Nitrogen is trivalent with a lone pair since it possesses five valence electrons.
- According to the theory of VSEPR, nitrogen in amines is sp3 hybridised. Because of the existence of a lone pair, the shape is pyramidal rather than the tetrahedral shape that most sp3 hybridised molecules have.
- The C-N-H angle in amines is less than 109 degrees, which is an angle of tetrahedral geometry due to the existence of a lone pair. Amines have an angle of roughly 107 degrees.
- Amines are found naturally in vitamins, proteins, hormones, and other compounds, and they are also synthesised to generate medicines, polymers, and colours.
Types of amines
Amines are classified into four categories based on how an ammonia molecule replaces hydrogen atoms.
|Types of amines||Examples|
|1o amines||When an alkyl or aryl group replaces one of the hydrogen atoms in the ammonia molecule.||Aniline, Methylamine|
|2o amines||An amine is formed when two organic substituents replace the hydrogen atoms in an ammonia molecule.||Diphenylamine, Dimethylamine|
|3o amines||An aryl or aromatic group is formed when an organic substituent replaces all three hydrogen atoms.||Ethylenediaminetetraacetic acid, Trimethylamine|
|Cyclic amines||These are 2o or 3o amines in an aromatic ring structure.||Aziridines, Piperidine|
Uses of amines
Uses of amines are,
- It is employed in the purification of water, the production of medicines, and the development of pesticides and insecticides.
- It plays a role in synthesising amino acids, which are the building blocks of proteins in living organisms. Amines are also responsible for the production of a wide range of vitamins.
- Amines are used to make pain relievers like Morphine and Demerol, also known as analgesics.
Amides [R(C = O)NR’R”]
Amides are organic compounds with a carbonyl functional group connected to an amine and a hydrogen atom or hydrocarbon group. A double-bonded carbon atom and an oxygen atom make up a carbonyl functional group.
- When the nitrogen atom of an amine is linked to a carboxyl group, an amide is created.
- Amide bonds can create hydrogen bonds with water because they are polar. The solubility of an amide decreases as the molar mass of the hydrocarbon substituent increases. Only the lower members of the amide family are water-soluble.
- The amide has a high boiling and melting point due to its solubility.
Classification of amides
Amides are classified into three groups based on the substituents connected to the nitrogen atom of the amide.
- Primary amide – A primary amide is one in which the amide’s nitrogen atom has only hydrogen atoms as a substituent.
- Secondary amide – The nitrogen atom of an amide is connected to a hydrocarbon substituent in a secondary amide.
- Tertiary amide – In a tertiary amide, the nitrogen is linked to three carbons.
- Cyclic amide – A cyclic amide is referred to as a lactam.
The common examples of amides are—acetamide with a molecular weight of 59.07, Benzamide with a molecular weight of 121.14, and dimethylformamide.
Uses of amides
Amides are commonly employed as structural materials in technologies. Polyamides are the most durable materials. An amide link is easy to make, hydrolysis resistant, and gives structural stiffness. A range of medications, including LSD, paracetamol, and penicillin, are amides.