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प्रश्न
Write the chemical equation involved in the following reaction:
Hoffmann-bromamide degradation reaction
Illustrate the following reaction giving a suitable example in the case:
Hoffmann bromamide degradation reaction
Write the reactions involved in Hofmann bromamide degradation reaction
Write the chemical equation involved in Hoffmann Bromamide degradation for acetamide.
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उत्तर १
- Primary amine can be prepared by reaction of the amide with bromine and aqueous or alcoholic sodium hydroxide. This reaction is known as Hoffmann bromamide degradation.
- It involves molecular rearrangement.
- An alkyl or aryl group migrates from the carbonyl carbon to the adjacent nitrogen atom.
- This reaction is useful for decreasing the length of carbon chain by one carbon atom.
\[\ce{CH3 - CO - NH2 + 4NaOH + Br2 ->CH3 - NH2 + Na2CO3 + 2NaBr + 2H2O}\]
उत्तर २
\[\ce{R - CO - NH2 + 4NaOH + Br2 ->R - CH2 - NH2 + Na2CO3 + 2NaBr + 2H2O}\]
\[\ce{CH3 - CH2 - CO - NH2 + 4NaOH + 2NaBr + 2H2O->CH3 - CH2 - NH2 + Na2CO3 + 2NaBr + 2H2O}\]
APPEARS IN
संबंधित प्रश्न
Write a short note on Hoffmann bromamide degradation.
An aromatic compound 'A' of molecular formula C7H7ON undergoes a series of reactions as shown below. Write the structures of A, B, C, D and E in the following reactions :
Give the structure of A, B and C in the following reaction:
\[\ce{CH3CH2Br ->[KCN] A ->[LiAlH4] B ->[HNO2][0^\circ C] C}\]
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.
Mention 'two' uses of propan-2-one.
Identify 'A' and 'B' in the following reaction and rewrite the complete reaction :
Give the structures of A, B and C in the following reactions :
Answer in one sentence.
Which amide does produce ethanamine by Hofmann bromamide degradation reaction?
Answer the following
Write a reaction to convert acetic acid into methylamine.
Answer the following
Explain Gabriel phthalimide synthesis.
Write reactions to prepare ethanamine from Acetonitrile.
Mendius reaction is used to convert _____________
Write the order of reactivity of alkyl halides with ammonia.
Write reactions to bring about the following conversions.
Acetamide to Ethylamine
Write reactions to bring about the following conversions.
Acetamide to methylamine
Alkyl cyanides on reduction by sodium and ethanol give primary amines. This reaction is called as ____________.
Identify the product obtained when benzyl chloride undergoes ammonolysis in presence of excess ammonia followed by the reaction with two moles of methyl iodide.
Which of the following amines forms a clear solution when treated with benzene sulphonyl chloride and excess of potassium hydroxide?
Which of the following reagents is used in Mendius reduction reaction of alkyl cyanide?
Which of the following compounds is obtained when quaternary ammonium hydroxide is strongly heated?
Which of the following does NOT give carbylamine test?
Which of the following reactions does NOT yield an amine?
Nitro compounds are reduced by iron scrap and hydrochloric acid to yield one of the following compounds:
Quaternary ammonium salt is formed:
Given below are two statements labelled as Assertion (A) and Reason (R).
Assertion (A): Alkyl halides are insoluble in water.
Reason (R): Alkyl halides have halogen attached to sp3 hybrid carbon.
Select the most appropriate answer from the options given below:
Amongst the following, the strongest base in aqueous medium is ______.
Benzylamine may be alkylated as shown in the following equation:
\[\ce{C6H5CH2NH2 + R - X -> C6H5CH2NHR}\]
Which of the following alkylhalides is best suited for this reaction through SN1 mechanism?
Which of the following reagents would not be a good choice for reducing an aryl nitro compound to an amine?
In order to prepare a 1° amine from an alkyl halide with simultaneous addition of one \[\ce{CH2}\] group in the carbon chain, the reagent used as source of nitrogen is ______.
The source of nitrogen in Gabriel synthesis of amines is ______.
The best reagent for converting, 2-phenylpropanamide into 1- phenylethanamine 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.\[\ce{H2 SO4}\].
What is the product when \[\ce{C6H5CH2NH2}\] reacts with \[\ce{HNO2}\]?
How will you bring out the following conversion?
How will you carry out the following conversion?
How will you carry out the following conversion?
Account for the following:
Aniline cannot be prepared by the ammonolysis of chlorobenzene under normal conditions.
The compound X is which of the following?
\[\ce{CH3CN ->[Na + C2H5OH] x}\]
In the given reaction what is the X?
\[\begin{array}{cc}
\ce{O}\phantom{.......................}\\
||\phantom{.......................}\\
\phantom{}\ce{R - C - OH <-[H3O] Χ ->[H] RCH2NH2}
\end{array}\]
Give reasons for the following:
Ammonolysis of alkyl halides is not a good method to prepare pure primary amines.
Which of the following reaction DOES NOT involve Hoffmann bromamide degradation?
- Phenyl methenamine
- N, N - Dimethylaniline
- N - Methyl aniline
- Benzenamine
Choose the correct order of the basic nature of the above amines.
The amine 'A' when treated with nitrous acid gives yellow oily substance. The amine A is ______.
Which of the following statement(s) is/are incorrect in case of Hofmann bromamide degradation?
What is the IUPAC name of \[\ce{(CH3)2 - N - CH3}\]?
Identify the product ‘C’ in the following reaction.
\[\ce{Aniline ->[(CH3CH)2O][Pyridine] A ->[Br2][CH3COOH] B ->[H^+ or OH^-] C}\]
Write the name of the product formed by the action of LiAlH4/ether on acetamide.
Write short note on the following:
Ammonolysis
Identify the compo ds A and B in the following reactions:
\[\ce{A ->[Nitrating mixture] B ->[(i) Sn/cone. HCI][(ii) NaOH] Aniline}\]
Identify A and B in the following reaction.
\[\ce{C6H5CH2Br ->[Alco.][KCN] A ->[Na/Ethanol][reduction] B}\]
Write a short note on the following:
Ammonolysis
Write a short note on Ammonolysis.
Write short note on the following.
Ammonolysis.
Write a short note on the following:
Ammonolysis.
