Question

Which among the following pairs of the structures will give different products onozonolysis? (Consider the double bonds in the structures are rigid and not delocalized)

• A.
• B.
• C.
• D.

Answer 1

The Correct Option is C

   To determine which pair of structures will give different products on ozonolysis, let's understand the ozonolysis reaction. Ozonolysis is a reaction where ozone (O₃) cleaves the carbon-carbon double bonds in alkenes to form carbonyl compounds (aldehydes or ketones).

Consider the fact that the double bonds in the structures are rigid and not delocalized, meaning the stereochemistry around the double bond can lead to different products depending on the substitution pattern.

Let us evaluate each pair:

1. Look at the first pair of structures:
   • These structures are symmetrical or have a similar substitution pattern around the double bond.
   • Ozonolysis of this pair will likely give the same products (or equivalent carbonyl compounds).
2. Now, consider the second pair:
   • These structures also have a similar substitution pattern around the double bond because they appear to be geometrically related (cis/trans).
   • The ozonolysis of this geometrically related pair can produce the same products due to the similar substitution pattern.
3. Now, examine the third pair:
   • These structures exhibit different substitution patterns.
   • Ozonolysis will lead to different carbonyl products due to these structural differences.
4. Finally, consider the fourth pair:
   • These structures appear to have similar substituents around the double bond.
   • Such a pair is likely to give the same products upon ozonolysis due to the symmetry or similar features.

Based on this analysis, the third pair will give different products on ozonolysis because of the distinct substitution pattern around the double bonds in the two structures.

Conclusion: The correct answer is the third pair

as they will produce different carbonyl products upon ozonolysis.