Which one of the following,with HBr will give | vedclass

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(B) The reaction of ethers with $HBr$ involves the protonation of the oxygen atom followed by nucleophilic attack by the bromide ion $(Br^-)$. In the

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Anisole (Methoxybenzene)

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(B) The reaction of ethers with $HBr$ involves the protonation of the oxygen atom followed by nucleophilic attack by the bromide ion $(Br^-)$. In the case of anisole $(C_6H_5OCH_3)$,the oxygen is attached to a phenyl group and a methyl group. Protonation gives $[C_6H_5-O^+(H)-CH_3]$. The $Br^-$ ion attacks the less sterically hindered methyl group via an $S_N2$ mechanism,resulting in the cleavage of the $O-CH_3$ bond. This produces phenol $(C_6H_5OH)$ and methyl bromide $(CH_3Br)$. Other ethers like benzyl methyl ether or benzyl tert-butyl ether would cleave to form benzyl bromide because the benzyl carbocation or transition state is stabilized by resonance,leading to the formation of methanol or tert-butyl alcohol instead of phenol.

Which one of the following,with $HBr$ will give a phenol?

Similar Questions

Identify the product of the following reaction:

Anisole $\xrightarrow[\text{reflux}]{\text{excess } HI \text{ (conc.)}} \text{ Product}$

In the given reaction
$C_6H_5 - O - CH_2 - CH_3 \xrightarrow{\text{Excess } HI / \Delta} [X] + [Y]$
$[X]$ and $[Y]$ will respectively be

The major product of the following reaction sequence is:

Assertion: Ethers behave as bases in the presence of mineral acids.
Reason: Due to the presence of lone pairs of electrons on oxygen.

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