Question

Which of the following statement(s) is/are true about schmidt rearrangement?

• A. Isocyanate intermediate is formed
• B. It is a free radical mechanism
• C. Acyl ion is formed during the reaction
• D. Both primary and secondary amines are produced by this reaction

Answer 1

Answer: (A), (C)

Acyl ion is formed during the reaction

Carboxylic acid reacts with hydrazoic acid to form amines. This reaction is called Schmidt rearrangement.

Mechanism:
Step 1: Here, carboxylic acid was protonated and water gets eliminated to form acylium ion.

Step 2: Hydrazoic acid attacks the acylium ion to form protonated azide.

Step 3: Abstraction of proton followed by elimination of $N_2$ and aryl group migration leads to the formation of isocyanate intermediate.

Step 4: Formed isocyanate gets hydrolysed to form primary amine and $C{O}_2$




Thus, (a) and (c) are true.