JEE Main 2017 · 8 Apr · Shift 1 · Chemistry Q55

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ChemistrySingle correct+4 / -1Question 55 of 90

The major product expected from the following reaction is :

Benzene ring bearing CO₂H, CH₂OH, CONH₂ and OH on adjacent carbons, treated with HCl(g)/CCl₄.

The lactone of CH₂OH with the amide carbon, keeping CO₂H and OH

Benzene ring with CO₂H, a five-membered lactone formed from CH₂-O and the former amide C=O, and OH.

CO₂H, CH₂OH and CONH₂ with OH replaced by Cl

Benzene ring with CO₂H, CH₂OH, CONH₂ and Cl (in place of OH).

The lactone of CH₂OH with CO₂H, keeping CONH₂ and OH

Benzene ring with a five-membered lactone formed from CH₂-O and the former CO₂H, plus CONH₂ and OH.

The lactone of CH₂OH with the amide carbon, keeping CO₂H, with OH replaced by Cl

Benzene ring with CO₂H, a five-membered lactone formed from CH₂-O and the former amide C=O, and Cl.

Answer and worked solution

Official answer: C

HCl catalyses lactonisation between the $\ce{CH2OH}$ group and the neighbouring $\ce{CO2H}$ (Fischer esterification inside the molecule, forming a five-membered lactone). The amide is much less reactive toward acyl substitution and stays, and the phenolic OH is not replaced. That is structure (3).

Topics:Acid derivatives Carboxylic acids

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JEE Main 2017 · 8 Apr · Shift 1, Chemistry question 55