Question

One mol of 2-Methylbuta-1,3-diene on ozonolysis gives

• A. 2 moles of methanal and 1 mole of propanone
• B. 2 moles of methanal and 1 mole of 2-ketopropanal
• C. 1 mole of methanal, 1 mole of ethanol, and 1 mole of propanone
• D. 2 moles of ethanal and 1 mole of 2-ketopropanal

Hint:

In ozonolysis, each \(C=C\) bond is cleaved and both double-bonded carbon atoms are converted into carbonyl groups. Terminal \(=CH_2\) groups give methanal.

Answer 1

The Correct Option is B

Step 1: Map each double bond to its ozonolysis products.
Isoprene: CH₂=C(CH₃)–CH=CH₂. Terminal =CH₂ carbons both → HCHO (methanal). Internal C(CH₃)= and =CH– together → CH₃–CO–CHO (2-ketopropanal).

Step 2: Final Answer:
2 moles methanal + 1 mole 2-ketopropanal (option 2).