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प्रश्न
What is meant by the following term? Give an example of the reaction in the following case.
Cyanohydrin
उत्तर
Aldehydes and ketones react with hydrogen cyanide (HCN) to yield cyanohydrins. This reaction occurs very slowly with pure HCN. Therefore, it is catalysed by a base and the generated cyanide ion (CN−) being a stronger nucleophile readily adds to carbonyl compounds to yield corresponding cyanohydrin.
\[\ce{HCN + O\overset{-}{H} <=> {_{\bullet}^{\bullet}}\overset{-}{C}N + H2O}\]
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संबंधित प्रश्न
Acetaldehyde, when treated with which among the following reagents does NOT undergo addition reaction?
(A) Ammonia
(B) Hydroxylamine
(C) Ammoniacal silver nitrate
(D) Semicarbazide
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Hint: Consider steric effect and electronic effect.
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Hint: Consider steric effect and electronic effect.
What is meant by the following term? Give an example of the reaction in the following case.
Acetal
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PhMgBr and then H3O+
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How are the following compounds prepared?
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2) `PCl_3 , "heat"`
3) `P_2O_5, "heat"`
What are amines?
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Which one of the following gives only one monochloro derivative?
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Write the name of product formed, when acetone is treated with 2, 4-dinitrophenyl hydrazine.
Arrange the following in the increasing order of their property indicated:
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Which of the following is most reactive in nucleophilic addition reactions?
Draw the structure of the following derivative.
The ethylene ketal of hexane-3-one
The product of the following reaction is
\[\begin{array}{cc}
\ce{O}\phantom{.........}\\
||\phantom{.........}\\
\ce{C2H5 - C - CH3 ->[H2/Ni][\Delta] \phantom{..}?}\end{array}\]
Draw structure of the following derivative.
The ethylene ketal of hexan-3-one
Draw structure of the following derivative.
The ethylene ketal of hexan-3-one
