Question

How is methyl cyanide obtained from acetamide?

Answer 1

In order to answer this question, we should know about the chemical formula of methyl cyanide and acetamide. By knowing about their chemical formula, we will come to know which functional groups are present and how they change into each other.

Complete Step By Step Answer:
Let’s understand this question in complete detail.
First, we should know what acetamide is. An acetamide is the simplest amide derived from acetic acids. It is as organic compound with the chemical formula $C{H_3}CON{H_2}$
On the other hand, methyl cyanide is given. It is the simplest organic compound that consists of a nitrile group. It is the chemical compound with the chemical formula $C{H_3}CN$ . It is often abbreviated as $MeCN$ .
Now, here in the question, acetamide is converted into methyl cyanide which indicates that amide group i.e. $- CON{H_2}$ is converted into cyanide group i.e. $- CN$ .
Here is the following reaction that occurs:

In the above reaction, when acetamide is heated with ${P_2}{O_5}$ . A molecule of water is eliminated and methyl cyanide is obtained.

Note:
We must remember the chemical formula of the compound given and the reagents so that the conversion of functional groups takes place. For example- in the given reaction, acetamide contains the group i.e. $- CON{H_2}$ which shows there is a carbon double bond with oxygen and a nitrogen is attached with that carbon. If we remove the oxygen and the two hydrogens attached with nitrogen then we will get a carbon triple bond with nitrogen i.e. a cyanide group. So, we need to choose a reagent which can remove water molecules.