Question

Identify phenacetin from the following:
(A)
(B)
(C)
(D)

Answer 1

To answer this you should know that phenacetin belongs to the class of acetamide. It is prepared by Williamson’s ether synthesis and thus is a derivative of ether too. We can write its general formula as ${{C}_{10}}{{H}_{13}}N{{O}_{2}}$. You can use this to determine its structure.

Complete step by step solution:
To answer this, firstly let us discuss the structure of phenacetin.
Phenacetin is a derivative of acetamide and an ether. It can be derived from Williamson’s ether synthesis reaction. It can be derived from N-phenylacetamide, 4-ethoxyaniline and paracetamol.
It is used as an analgesic. It is a painkiller and it was the world's first synthetic pharmaceutical drug. Its effects are due to its actions on the sensory tract of the spinal cord.
Now, let us see its structure.
It is an organic compound and it belongs to the class of acetamide. An acetamide is an amide derivation of acetic acid. In phenacetin, one hydrogen atom of the group is substituted by a 4 – ethoxy phenyl group. We can draw its structure as-

So, we can understand from the above discussion that the correct answer is option (D).

Note: In Williamson’s ether synthesis, an alkoxide anion undergoes substitution nucleophilic bimolecular reaction with an alkyl halide and forms ether. We generally carry out this reaction for the formation of unsymmetrical ethers. We will take an example to understand the mechanism of this reaction-

Here we have to use a strong base, $NaH$ to form the alkoxide anion as alcohols are a weak acid and methyl iodide is used here which is the electrophile.