Primary Amine Synthesis by Rearrangement

Hofmann and Curtius rearrangements are used to make primary amines from carboxylic acid derivatives. In the Hofmann rearrangement, a primary amide is treated with a base and then halogenated to form an N-haloamide. A second proton loss gives a stable anionic species that rearranges to an isocyanate after an alkyl group migra...

Hofmann and Curtius rearrangements convert different carboxylic acid derivatives to primary amines.

Hofmann rearrangement begins with the base abstracting the N–H proton, followed by an α-substitution reaction with the halogen to form an N-haloamide.

Abstracting the second N–H proton provides a resonance-stabilized a...