Question

Which of the following ether is called phenetole?
[A]$PhOC{{H}_{3}}$
[B]$PhO{{C}_{2}}{{H}_{5}}$
[C]$PhO{{C}_{3}}{{H}_{7}}$
[D]$p-N{{O}_{2}}-{{C}_{6}}{{H}_{4}}-O{{C}_{2}}{{H}_{5}}$

Answer 1

Hint: Phenetole is an organic ether i.e. it has an –O-alkyl, an alkoxy group. It is also called ethyl-phenyl-ether and we can assume its structure from its name.

Complete step by step solution:
Ethyl phenyl ether or phenetole is an organic ether which is formed by Williamson synthesis of sodium phenoxide with bromoethane.
Williamson synthesis is an organic reaction which uses an organohalide and a deprotonated alcohol to give us ether-

Following the above reaction mechanism, we can write the reaction for the formation of ethyl phenyl ether as-

Sodium phenoxide + bromoethane$\to $phenetole + sodium bromide
In phenetole, the oxygen atom is bonded to an ethyl group and a phenyl group.
The derivation of the name phenetole is ‘phen’ for the phenyl group ‘et’ for the ethyl group and ‘ole’ for its oily appearance.
However, commonly it is known as ethoxybenzene and this is its IUPAC name.
As we can see from the above reaction, phenetole has a phenyl and an ethyl group attached by an oxygen atom therefore phenetole is$PhO{{C}_{2}}{{H}_{5}}$where the ethyl group is combined and written as ${{C}_{2}}{{H}_{5}}$.
Therefore, the correct answer is option [B]$PhO{{C}_{2}}{{H}_{5}}$.

ADDITIONAL INFORMATION: Phenetole is an ether and has similar properties like other ethers. It is volatile and forms peroxides. It is insoluble in polar solvents like water but dissolves in less polar solvents like ethanol and other ethers.

Note: We should remember that ${{C}_{2}}{{H}_{5}}$is the ethoxy group and not methoxy and we should also focus on the point that it is formed from ethyl bromide. Therefore, in its structure it will have an ethyl group and not a methyl group.
If there was a methoxy group instead of the ethoxy group, we would get $PhOC{{H}_{3}}$, which is phenoxyethanol and is also known as anisole.