Question

Explain Hoffmann bromamide degradation reaction and write the general equation for the reaction involved.

Answer 1

Hoffmann bromamide degradation:

• Hoffmann bromamide reaction is used to convert amides into amines.
• Amides are the compound in which the carbonyl group is attached by a single bond with Nitrogen $({}_3\mathrm{HC}-\underset{\underset{ }{\overset{\parallel }{O}}}{C}-{\mathrm{NH}}_2)$
• The amides in the reaction combined with ${\mathrm{Br}}_2$ and an aqueous solution of base such as $\mathrm{NaOH}$.
• The product amine is always one carbon less than the number of Carbon in reacting amides because the carbonyl group react with base and forms a compound.

$\mathrm{R}-\underset{\underset{ }{\overset{\parallel }{O}}}{\mathrm{C}}-{\mathrm{NH}}_2+{\mathrm{Br}}_2+4\mathrm{NaOH}\to \mathrm{R}-{\mathrm{NH}}_2+{\mathrm{Na}}_2{\mathrm{CO}}_3+2\mathrm{NaBr}+2{\mathrm{H}}_2\mathrm{O}$

• The General Equation for the reaction involved can be given as:

$\mathrm{R}-\underset{\underset{ }{\overset{\parallel }{O}}}{\mathrm{C}}-{\mathrm{NH}}_2+{\mathrm{X}}_2\underset{\mathrm{\Delta }}{\overset{\mathrm{Base}+{\mathrm{H}}_2\mathrm{O}}{\to }}\mathrm{R}-{\mathrm{NH}}_2$, Here $\mathrm{X}=\mathrm{Cl}\mathrm{or}\mathrm{Br}$