Carboxylic Acids and their Derivatives - Result Question 58-1

58. Give reasons for the following in one or two sentences.

“Acetic acid can be halogenated in the presence of P and $\mathrm{Cl}_2$, but formic acid cannot be halogenated in the same way.” Why?

(1983, 1M)

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Solution:

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For this reaction to occur, presence of a $\alpha$-H is essential requirement. Formic acid does not has any $\alpha$-H, fails in HVZ reaction.