Q.67. Consider the following sequence of reactions [Figure: Reaction scheme starting with phenol, re

Q: What is the correct answer for JEE Main Chemistry Q67?

The correct answer is C. The reaction sequence is: 1. Phenol is heated with Cu at 573 K. This is a dehydrogenation reaction. Phenol (an alcohol) undergoes dehydrogenation to form a ketone. Cyclohexanol would form cyclohexanone. Phenol, being aromatic, would not typically undergo this reaction to form a ketone. However, if we consider the ring as a cyclohexanol derivative, it would be oxidized to a ketone. But phenol is a

Q: Q.67. Consider the following sequence of reactions [Figure: Reaction scheme starting with phenol, reacting with (i) Cu/573 K, (ii) H, PhCOOH to give product P]. The major product P is :

The correct answer is C. The reaction sequence is: 1. Phenol is heated with Cu at 573 K. This is a dehydrogenation reaction. Phenol (an alcohol) undergoes dehydrogenation to form a ketone. Cyclohexanol would form cyclohexanone. Phenol, being aromatic, would not typically undergo this reaction to form a ketone. However, if we consider the ring as a cyclohexanol derivative, it would be oxidized to a ketone. But phenol is a

Q: What are the options for this JEE Main Chemistry question?

A. [Structure of Benzoic acid] · B. [Structure of 4-hydroxybenzoic acid] · C. [Structure of Phenyl benzoate] · D. [Structure of Diphenyl ether]

Question

Q.67. Consider the following sequence of reactions [Figure: Reaction scheme starting with phenol, reacting with (i) Cu/573 K, (ii) H, PhCOOH to give product P]. The major product P is :

FirstInTest · Accepted Answer

The reaction sequence is:
1.  Phenol is heated with Cu at 573 K. This is a dehydrogenation reaction. Phenol (an alcohol) undergoes dehydrogenation to form a ketone. Cyclohexanol would form cyclohexanone. Phenol, being aromatic, would not typically undergo this reaction to form a ketone. However, if we consider the ring as a cyclohexanol derivative, it would be oxidized to a ketone. But phenol is an aromatic alcohol. The reaction of phenol with Cu/573K is not a standard reaction to form a ketone. It usually leads to oxidation or decomposition. However, if we interpret the initial reactant as cyclohexanol, then it would form cyclohexanone. The image shows phenol as the starting material. Let's assume the first step is an oxidation to a ketone if possible, or perhaps it's a typo and should be cyclohexanol. Given the options, the product P is an ester.

Let's re-examine the reaction. The starting material is phenol. The first step (i) Cu/573 K is typically for dehydrogenation of alcohols. Phenol is an aromatic alcohol. This step is unusual for phenol to form a ketone. However, if we consider the overall transformation to an ester, it implies a carboxylic acid derivative.

The second step (ii) H$^+$, PhCOOH indicates esterification with benzoic acid (PhCOOH). For esterification, we need an alcohol. If phenol reacts with benzoic acid, it forms phenyl benzoate (an ester). The reaction is: Phenol + PhCOOH $\xrightarrow{\mathrm{H^+}}$ Phenyl benzoate (Ph-O-CO-Ph).

Let's look at the options. Options A and B are carboxylic acids. Options C and D are esters. Option C is phenyl benzoate. Option D is an ether or a different ester.

If the first step (Cu/573K) is meant to convert phenol to something that can react with PhCOOH, it's not straightforward. However, if the question implies a direct reaction of phenol with PhCOOH, then esterification would occur.

Let's assume the question implies the direct reaction of phenol with benzoic acid in the presence of an acid catalyst (H$^+$). This would yield phenyl benzoate.

Phenol + Benzoic acid $\xrightarrow{\mathrm{H^+}}$ Phenyl benzoate + H$_2$O

Phenyl benzoate is an ester where the -OH of phenol reacts with the -COOH of benzoic acid. The structure of phenyl benzoate is a benzene ring attached to an oxygen, which is then attached to a carbonyl group, which is then attached to another benzene ring. This matches option (3).

Answer

[Structure of Benzoic acid]

Answer

[Structure of 4-hydroxybenzoic acid]

Answer

[Structure of Phenyl benzoate]

Answer

[Structure of Diphenyl ether]

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