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Karnataka Board PUCPUC Science 2nd PUC Class 12

In Kolbe’s reaction, instead of phenol, phenoxide ion is treated with carbon dioxide. Why?

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Question

In Kolbe’s reaction, instead of phenol, phenoxide ion is treated with carbon dioxide. Why?

Short/Brief Note
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Solution

Phenoxide ion is more reactive than phenol towards electrophilic substitution. The negative charge on oxygen is transferred to benzene through resonance. This helps in the attachment of CO2 which is a weak electrophile to the benzene ring finally giving salicylic acid.

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Chapter 11: Alcohols, Phenols and Ethers - Multiple Choice Questions (Type - I) [Page 160]

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NCERT Exemplar Chemistry Exemplar [English] Class 12
Chapter 11 Alcohols, Phenols and Ethers
Multiple Choice Questions (Type - I) | Q 48 | Page 160

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