Which of the following compound will undergo Cannizzaro reaction?
Answer & explanation
Correct answer: option 1
The correct answer is Option (1) → Methanal
Core Concept - Cannizzaro Reaction
Cannizzaro reaction is shown by aldehydes that do NOT have $α$-hydrogen. In strong base, such aldehydes undergo disproportionation → one molecule is oxidized to acid (salt) and the other reduced to alcohol.
Option 1: Methanal (HCHO)
Methanal has no $α$-carbon, hence no a-hydrogen. It readily undergoes Cannizzaro reaction forming methanol + sodium formate. So this compound does react.
Option 2: Cyclohexanone
It is a ketone, not an aldehyde. Cannizzaro reaction is specific to aldehydes lacking $α$-H. Ketones generally do not undergo this reaction.
Option 3: Propanal
Propanal has $α$-hydrogen atoms. Such aldehydes prefer aldol condensation instead of Cannizzaro. Hence, it does not undergo Cannizzaro reaction.
Option 4: Acetone
Acetone is a ketone with a-hydrogens. It undergoes aldol reaction, not Cannizzaro reaction. Therefore, it does not qualify.