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Write a short note on the following: Hoffmann’s bromamide reaction

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Question

Write a short note on the following:

Hoffmann’s bromamide reaction

Chemical Equations/Structures
Short/Brief Note
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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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Chapter 9: Amines - Exercises [Page 279]

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NCERT Chemistry Part 1 and 2 [English] Class 12
Chapter 9 Amines
Exercises | Q 9.7 (iii) | Page 279

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