Question
Explain Hell-Volhard-Zelinsky reaction of carboxylic acids.
✓
Answer
→ Carboxylic acids having an $\alpha$-hydrogen are halogenated at the $\alpha$-position on treatment with chlorine or bromine in the presence of small amount of red phosphorus to give $\alpha$-halocarboxylic acids. The reaction is known as Hell-Volhard-Zelinsky reaction.
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