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COMEDK2025ChemistryAlcohols Phenols and EthersActual

What are the intermediates formed during the reactions A and B ? A. Reimer-Tiemann reaction. B. Dehydration of alcohols in the slow rate determining step.

Correct answer

3

Step-by-step solution

A. Reimer-Tiemann Reaction: Phenol is treated with CHCl₃ and NaOH . The base generates dichlorocarbene (:CCl₂) , which attacks the ortho position of the phenoxide ion. The intermediate is sodium 2-(dichloromethyl)phenolate — a phenoxide ring with an ortho -CHCl₂ group (option 4, structure A). B. Dehydration of Alcohols (slow step): In acid-catalyzed E1 dehydration, the slow rate-determining step is the breaking of the C - O bond after protonation of -OH , forming a carbocation R^+ . The intermediate is the carbocat

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