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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
Give simple chemical tests to distinguish between the following pairs of compounds: Benzoic acid and Phenol
Write the main products when
2, 4, 6-trinitrochlorobenzene is subjected to hydrolysis
Picric acid is ____________.
When phenol is heated with CHCl3 and alcoholic KOH when salicylaldehyde is produced. This reaction is known as ____________.
The electrophile involved in Reimer-Tiemann reaction of phenol with CHCl3 in presence of NaOH:
\[\ce{C2H5OH + SOCl2 ->[Pyridine] C2H5Cl + SO2 + HCl}\]
The above reaction is known as:
Which of the following reactions is used to prepare salicylaldehyde?
Phenol does not undergo nucleophilic substitution reaction easily due to ______.
Which of the following are used to convert \[\ce{RCHO}\] into \[\ce{RCH2OH}\]?
(i) \[\ce{H2/Pd}\]
(ii) \[\ce{LiAlH4}\]
(iii) \[\ce{NaBH4}\]
(iv) Reaction with \[\ce{RMgX}\] followed by hydrolysis
Which of the following are benzylic alcohols?
(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) \[\begin{array}{cc}
\ce{C6H5 - CH2 - CH - OH}\\
\phantom{.......}|\phantom{}\\
\phantom{.........}\ce{CH3}\phantom{}
\end{array}\]
Convert the following:
Phenol to N-phenylethanamide.
Which of the following is not aromatic?
Attacking species in nitration of benzene in presence of fuming HNO3 is
Which of the following reacts with phenol to give salicylaldehyde after hydrolysis?
Why ortho-nitrophenol is steam volatile while para-nitrophenol is not?
How can phenol be prepared from anisole? Give reaction.
Write the name of the reaction, structure and IUPAC name of the product formed when:
Phenol reacts with CHCl3 in the presence of NaOH followed by hydrolysis.
Convert the following by giving a chemical equation:
Phenol to salicylaldehyde.
