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प्रश्न
Write the equation involved in the following reaction:
Reimer-Tiemann reaction
Explain the following with an example.
Reimer-Tiemann reaction
Write a chemical equation to illustrate the following name reaction:
Reimer-Tiemann reaction
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उत्तर १
On treating phenol with chloroform in the presence of sodium hydroxide, a -CHO group is introduced at the ortho position of the benzene ring. This reaction is known as the Reimer-Tiemann reaction. The intermediate substituted benzal chloride is hydrolysed in the presence of alkali to produce salicylaldehyde.
उत्तर २
उत्तर ३
Phenol reacts with sodium hydroxide (or KOH) and chloroform in this reaction. 4-hydroxybenzaldehyde is a minor product, while salicylaldehyde is the primary product. Steam distillation can be used to separate it from the p-isomer. Intramolecular hydrogen bonding is responsible for the stability of the p-isomer.
Notes
Students should refer to the answers according to their questions and provide marks.
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संबंधित प्रश्न
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(i) \[\ce{H2/Pd}\]
(ii) \[\ce{LiAlH4}\]
(iii) \[\ce{NaBH4}\]
(iv) Reaction with \[\ce{RMgX}\] followed by hydrolysis
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(i) \[\ce{C6H5 - CH2 - CH2OH}\]
(ii) \[\ce{C6H5 - CH2OH}\]
(iii) \[\begin{array}{cc}
\ce{C6H5 - CH - OH}\\
\phantom{}|\phantom{.}\\
\phantom{..}\ce{CH3}\phantom{}
\end{array}\]
(iv) \[\begin{array}{cc}
\ce{C6H5 - CH2 - CH - OH}\\
\phantom{.......}|\phantom{}\\
\phantom{.........}\ce{CH3}\phantom{}
\end{array}\]
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