Carboxylic Acids and their Derivatives - Result Question 72
####58. Give reasons for the following in one or two sentences.
“Acetic acid can be halogenated in the presence of $P$ and $Cl _2$, but formic acid cannot be halogenated in the same way.” Why?
(1983, 1M)
Show Answer
Solution:
- $CH _3-COOH+Cl _2 \xrightarrow{\text { Red- } P} \underset{Cl}{CH _2}-COOH$ (HVZ reaction)
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.
