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Question
Write a short note on the following:
Hoffmann’s bromamide reaction
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Solution
Hoffmann developed a method for preparation of primary amines by treating an amide with bromine in an aqueous or ethanolic solution of sodium hydroxide. In this degradation reaction, migration of an alkyl or aryl group takes place from carbonyl carbon of the amide to the nitrogen atom. The amine so formed contains one carbon less than that present in the amide.
\[\begin{array}{cc}
\ce{O}\phantom{.............................................................}\\
||\phantom{.............................................................}\\
\ce{R - C - NH2 + Br2 + 4NaOH -> R - NH2 + Na2CO3 + 2NaBr + 2H2O}
\end{array}\]
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Write a short note on the following:
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Write short note on the following:
Ammonolysis
Write short note on the following.
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Write a short note on the following:
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