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प्रश्न
Answer the following
Explain the ammonolysis of alkyl halides.
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उत्तर
i. When alkyl halide is heated with an alcoholic solution of excess ammonia, it undergoes a nucleophilic substitution reaction in which the halogen atom is replaced by an amino (–NH2) group to form primary amine.
ii. This process of breaking of the C – X bond by ammonia is known as ammonolysis. The reaction is also known as the alkylation of ammonia. The reaction is carried out in a sealed tube at 373 K.
iii. The primary amine obtained in the1st step is stronger nucleophile than ammonia. Hence, it further reacts with an alkyl halide to form secondary and tertiary amines and finally quaternary ammonium salt if NH3 is not used in large excess.
\[\ce{\underset{\text{Alkyl halide}}{R - X} + \underset{\text{(excess)}}{NH3_{(alc.)}}->[\Delta] \underset{1^0}{R} - NH2 + HX}\]
iv. The order of reactivity of alkyl halides with ammonia is R–I > R–Br > R–Cl.
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संबंधित प्रश्न
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Hoffmann-bromamide degradation reaction
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Give the structure of A, B and C in the following reaction:
\[\ce{CH3CH2Br ->[KCN] A ->[LiAlH4] B ->[HNO2][0^\circ C] C}\]
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Answer in one sentence.
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\[\ce{Nitrobenzene ->[Sn/conc.HCl]?}\]
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\[\ce{Acetonitrile ->[Na/alcohol] A ->[NaNO2/dil.HCI] B}\]
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(i) Isobutyl amine
(ii) 2-Phenylethylamine
(iii) N-methylbenzylamine
(iv) Aniline
Under which of the following reaction conditions, aniline gives p-nitro derivative as the major product?
(i) Acetyl chloride/pyridine followed by reaction with conc.\[\ce{H2SO4 }\] + conc. \[\ce{HNO3}\].
(ii) Acetic anyhdride/pyridine followed by conc.\[\ce{H2SO4}\] + conc.\[\ce{HNO3}\].
(iii) Dil. HCl followed by reaction with conc.\[\ce{H2SO4}\] + conc.\[\ce{HNO3}\].
(iv) Reaction with conc.\[\ce{HNO3}\] + conc.\[\ce{H2 SO4}\].
Identify A and B in the following reaction.
How will you bring out the following conversion?
Match the reactions given in Column I with the statements given in Column II.
| Column I | Column II | ||
| (i) | Ammonolysis | (a) | Amine with lesser number of carbon atoms |
| (ii) | Gabriel phthalimide synthesis | (b) | Detection test for primary amines. |
| (iii) | Hoffmann Bromamide reaction | (c) | Reaction of phthalimide with \[\ce{KOH}\] and \[\ce{R-X}\] |
| (iv) | Carbylamine reaction | (d) | Reaction of alkylhalides with \[\ce{NH3}\] |
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\[\begin{array}{cc}
\ce{O}\phantom{.......................}\\
||\phantom{.......................}\\
\phantom{}\ce{R - C - OH <-[H3O] Χ ->[H] RCH2NH2}
\end{array}\]
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Write a short note on the following:
Ammonolysis
Write a short note on the following:
Ammonolysis
Write a short note on Ammonolysis.
Write short note on the following.
Ammonolysis.
Assertion: Amimonolysis of alkyl halides involves the reaction between alkyl halides and alcoholic ammonia.
Reason: Ammonolysis of alkyl halides produces secondary amines only.
Write a short note on the following:
Ammonolysis.
Write short notes on the following:
Ammonolysis
Write a short note on the following:
Ammonolysis
