Question
Question: Identify tertiary amide. (A) \(C{{H}_{3}}CO-N(C{{H}_{3}})C{{H}_{2}}C{{H}_{3}}\) (B) \(C{{H}_{3}...
Identify tertiary amide.
(A) CH3CO−N(CH3)CH2CH3
(B) CH3CONH2
(C) CH3CO−NHCH3
(D) None of these.
Solution
On the basis of the number of alkyl/aryl groups attached to the remaining two bonds of the nitrogen atom in the amide group determines the type of amide as a simple or substituted amide.
Complete step by step solution:
In the general formula of amide, it has a nitrogen atom linked to the carbonyl carbon. These can further be subdivided on the basis of the number of carbons atoms or alkyl/ aryl groups attached to the nitrogen atom as follows:
- When only two hydrogen atoms are attached to the nitrogen group. It is called the simple amide or the primary amide.
- When one of the hydrogen bonds is replaced by the alkyl/ aryl group attached to the nitrogen atom, it forms the secondary amide.
- When both the bonds of nitrogen are formed with the alkyl/ aryl group, it forms the tertiary amide.
So, both the secondary and tertiary amides are known as a substituted amide.
Thus, in the given molecules CH3CONH2 having only hydrogens attached to the amide group is a primary amide. In CH3CO−NHCH3 molecule, with only one bond formed with the methyl group and the other with hydrogen is a secondary amide. And in CH3CO−N(CH3)CH2CH3 having two methyl groups attached to the amide group is a tertiary amide.
Therefore, the tertiary amide is option (A)- CH3CO−N(CH3)CH2CH3.
Note: The general formula of primary amide will be RCO−NH2 , for the secondary amide it will be RCO−NHR and for the tertiary amide it will be RCO−NR2, where R can be a same or different alkyl or aryl groups.