What is an Amide?
Amides are compounds that have a carbonyl functional group that is linked to both an amine and a hydrocarbon group (or hydrogen atom). A carbonyl functional group is made up of a double-bonded carbon atom and an oxygen atom.
An amide’s general structure is R(C = O)NR’R”, where R, R’ and R” represent a hydrocarbon or a hydrogen substituent.
Table of Contents
- What is an Amido?
- Synthesis of Amides
- Properties of Amides
- Examples of Amides
- Classification of Amides
- Applications
- Frequently Asked Questions – FAQs
What is an Amido?
There is not much difference between Amido and Amides. In chemistry, Amido indicates the presence of an amide group.
Synthesis of Amides
Amine Acylation
An amide is formed by the reaction of an amine with an acyl group (a carboxylic acid derivative).
In amines, the nitrogen atom has a lone pair (non-bonded) of electrons that attacks the electron-deficient carbonyl carbon and forms a bond with it. The elimination of a proton (from the amine substituent) and the leaving group yields the corresponding amide.
Nitrile Hydrolysis
The formation of amides is caused by the partial hydrolysis of nitriles (RCN) under acidic or basic conditions.
Beckmann Rearrangement
Beckmann rearrangement is one of the most important amide synthesis methods.
The reaction entails the formation of an amide from an oxime group. The rearrangement of oximes in the presence of an activating agent, such as H2SO4 or PCl3, results in the formation of an amide.
Properties of Amides
- An amide is formed when the nitrogen atom of an amine is attached to a carboxyl group.
- The amide bond is polar, and therefore, it can form hydrogen bonds with water. As a result, amides are water-soluble (but only the lower members). The solubility of an amide decreases as the molar mass of its hydrocarbon substituent increases.
- The amide’s high boiling and melting points are due to its solubility.
- Amides are less basic than amines because the lone pair of electrons on the nitrogen atom of the amide is conjugated with the carbonyl group, making the electrons less available for donation.
Read More: Amine Amide Imine
Examples of Amides
Acetamide H3C-CONH2, benzamide C6H5CONH2, and dimethylformamide HCON(CH3)2 are examples of amides.
Classification of Amides
Amides are divided into three types based on the substituents attached to the amide’s nitrogen atom.
Primary, secondary, and tertiary amides are the three types of amides.
- A primary (1°) amide is one in which the substituent on the nitrogen atom of the amide is only hydrogen atoms.
- A secondary (2°) amide is one in which the amide’s nitrogen atom is linked to a hydrocarbon substituent.
- The nitrogen in a tertiary (3°) amide is attached to three carbons.
- Lactam is the name given to a cyclic amide.
Applications
Amides are widely used in technology as structural materials. An amide connection is simple to form, resistant to hydrolysis and provides structural rigidity. The most durable materials are polyamides and nylons. A variety of drugs are amides, including penicillin, LSD, and paracetamol. Furthermore, plant N-alkylamides have a diverse set of biological functions.
Frequently Asked Questions on Amido and Amide
What is the distinction between an amide and an amine?
The primary distinction between amine and amide is the presence of a carbonyl group in their structures; amines have no carbonyl groups attached to the nitrogen atom, whereas amides have a carbonyl group attached to the nitrogen atom.
What are the examples of amides?
Nylon, paracetamol, and dimethylformamide are examples of amides. The most basic amides are ammonia derivatives. Amphetamines, in general, are very weak bases.
What are the three different types of amides?
Based on their names, amides are classified into three types: primary amide, secondary amide, and tertiary amide.
What are the properties of amides?
The boiling and melting points of amides are generally high. These properties, as well as their solubility in water, are due to the amide group’s polarity and hydrogen bonding.
How are amides synthesised?
Simple amides can be synthesised by reacting an acid anhydride with an amine. A direct reaction between a carboxylic acid and an amine can also produce amides.
Comments