Aryl Halides and Phenols - Result Question 13

16. Phenol reacts with methyl chloroformate in the presence of $NaOH$ to form product $A$. $A$ reacts with $Br _2$ to form product $B$. $A$ and $B$ are respectively

(2018 Main)

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Answer:

Correct Answer: 16. (c)

Solution:

Given,

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In the above road map, first reaction appears as acid base reaction followed by $S _N AE$ (Nucleophilic substitution through Addition and Elimination). Both the steps are shown below

(i) Acid base reaction

(ii) $S _N A E$

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In the product of $S _N AE$ the attached group is ortho and para-directing due to following cross conjugation

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Cross conjugation due to which lone pair of oxygen $1$ will be easily available to ring resulting to higher electron density at $2 , 4, 6$ position with respect to group. However from the stability point of view ortho positions are not preferred by substituents as

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Hence, on further bromination of $S _N AE$ product para bromo derivative will be the preferred product i.e.

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