Preparation of AminesAmines
What is the rate-determining rearrangement step in the Hoffmann Bromamide mechanism, and what is the stable intermediate formed immediately after this step?
Expert Answer
The crucial step is the Wolff-like Rearrangement (migration of the alkyl/aryl group 'R' with its electron pair from carbonyl carbon to nitrogen) of the unstable acyl nitrene. This leads to the formation of an Isocyanate ( ) intermediate, which is subsequently hydrolyzed by the base.