Question

The List-I contains products obtained from the reaction of compounds in List-I with \(\mathrm{O_3/Zn-H_2O}\) followed by cyclization (via more stable enolate) in the presence of aqueous \(\mathrm{NaOH}\). Match each entry in List-I with appropriate entry in List-II and choose the correct option.

• A. \(P \rightarrow 2;\ Q \rightarrow 4;\ R \rightarrow 1;\ S \rightarrow 3\)
• B. \(P \rightarrow 3;\ Q \rightarrow 4;\ R \rightarrow 5;\ S \rightarrow 2\)
• C. \(P \rightarrow 2;\ Q \rightarrow 1;\ R \rightarrow 5;\ S \rightarrow 3\)
• D. \(P \rightarrow 3;\ Q \rightarrow 5;\ R \rightarrow 4;\ S \rightarrow 2\)

Hint:

Important reactions involved:
• Ozonolysis: \[ \mathrm{C=C \xrightarrow[Zn/H_2O]{O_3} Carbonyl\ compounds} \]
• Intramolecular aldol reaction: Enolate attacks intramolecular carbonyl center to form cyclic \(\beta\)-hydroxy carbonyl compounds.
• More substituted enolates are generally more stable and dominate under thermodynamic conditions. In cyclic systems, always analyze:
• ring strain
• favored ring size
• stability of enolate intermediate before predicting the major cyclized product.

Answer 1

The Correct Option is B