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प्रश्न
In Kolbe’s reaction, instead of phenol, phenoxide ion is treated with carbon dioxide. Why?
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उत्तर
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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संबंधित प्रश्न
Give reasons for the following:
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Give the equation of the following reaction:
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When 3-methylbutan-2-ol is treated with HBr, the following reaction takes place:
\[\begin{array}{cc}
\phantom{...................................}\ce{Br}\\
\phantom{..................................}|\\
\ce{CH3 - CH - CH - CH3 ->[HBr] CH3 - C - CH2 - CH3}\\
|\phantom{.........}|\phantom{...................................}|\phantom{...........}\\
\ce{CH3}\phantom{...}\ce{OH}\phantom{...............................}\ce{CH3}\phantom{.......}\\
\end{array}\]
Give a mechanism for this reaction.
(Hint: The secondary carbocation formed in step II rearranges to a more
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(i) H2/Pd
(ii) LiAlH4
(iii) NaBH4
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Suggest a reagent for the following conversion.
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Write the mechanism of acid dehydration of ethanol to yield ethene.
Write the mechanism of acid-catalysed dehydration of ethanol to yield ethene.
Write the mechanism of acid dehydration of ethanol to yield ethene.
Write the mechanism of acid-catalysed dehydration of ethanol to yield ethene
