Question

Which of the following acids does NOT undergo Hell–Volhard–Zelinsky reaction?

• A. Butanoic acid
• B. Propanoic acid
• C. Ethanoic acid
• D. Methanoic acid

Hint:

HVZ reaction is possible only when a carboxylic acid has at least one \(\alpha\)-hydrogen atom.

Answer 1

The Correct Option is D

Step 1: Recall the condition for HVZ reaction.
Hell–Volhard–Zelinsky (HVZ) reaction occurs in carboxylic acids containing at least one \(\alpha\)-hydrogen atom. The reaction involves \(\alpha\)-halogenation of the acid.

Step 2: Analyze each acid.
Butanoic acid: Contains \(\alpha\)-hydrogen, so it undergoes HVZ reaction.
Propanoic acid: Contains \(\alpha\)-hydrogen, so it undergoes HVZ reaction.
Ethanoic acid: Contains \(\alpha\)-hydrogen, so it undergoes HVZ reaction.
Methanoic acid: Does not contain any \(\alpha\)-carbon or \(\alpha\)-hydrogen.

Step 3: Conclusion.
Since methanoic acid lacks an \(\alpha\)-hydrogen, it does not undergo the HVZ reaction.