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प्रश्न
Why cannot aromatic primary amines be prepared by Gabriel phthalimide synthesis?
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उत्तर
Gabriel synthesis is used for the preparation of primary amines. Phthalimide, on treatment with ethanolic potassium hydroxide, forms potassium salt of phthalimide, which on heating with alkyl halide followed by alkaline hydrolysis produces the corresponding primary amine. Aromatic primary amines cannot be prepared by this method because aryl halides do not undergo nucleophilic substitution with the anion formed by phthalimide.
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संबंधित प्रश्न
Give the structure of A, B and C in the following reaction:
\[\ce{C6H5NO2 ->[Fe/HCl] A ->[NaNO2 + HCl][273 K] B ->[H2O/H+][\Delta] C}\]
Explain the mechanism of action of hydroiodic acid on 3-methylbutan-2-ol.
Why cannot aniline be prepared by Gabriel phthalimide synthesis?
Explain the following reaction with a suitable example.
Hofmann elimination reaction
Identify compound 'B' in following series of reactions?
\[\ce{Acetonitrile ->[Na/alcohol] A ->[NaNO2/dil.HCI] B}\]
Acetamide on reduction using Na/C2H5OH gives ____________.
Identify the product obtained, when benzamide is treated with bromine and aqueous sodium hydroxide.
What is the molar mass of the amine formed when acetamide undergoes Hofmann bromamide degradation?
Which of the following reactions is appropriate for converting benzamide to aniline?
Amongst the following, the strongest base in aqueous medium is ______.
Reduction of aromatic nitro compounds using \[\ce{Fe}\] and \[\ce{HCl}\] gives ______.
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.\[\ce{H2 SO4}\].
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 \[\ce{NH3}\] |
Account for the following:
Aniline cannot be prepared by the ammonolysis of chlorobenzene under normal conditions.
When primary amines are treated with HCl, the product obtained is which of the following?
A compound 'A' on reduction with iron scrap and hydrochloric acid gives compound 'B' with molecular formula C6H7N. Compound 'B' on reaction with CHCl3 and alcoholic KOH produces an obnoxious smell of carbylamine due to the formation of 'C'. Identify 'A', 'B' and 'C' and write the chemical reactions involved.
Write a short note on the following:
Ammonolysis
Write a short note on Ammonolysis.
