Product(s) formed in the given reaction sequence is(are)
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Ozonolysis of a ring alkene \(\Rightarrow\) 1,6-dicarbonyl; under base, intramolecular aldol can “stitch” an aromatic ring.
Keto–enol tautomerization of a conjugated diketone generated in such annulations often favors the \textbf{phenol} (naphthol) form.
Pd/C commonly serves to aromatize dihydroarenes; it doesn’t remove phenolic OH in the absence of specific reagents.
Step 1: Ozonolysis outcome.
Cleavage of the endocyclic C=C by O\(_3\) gives a \emph{1,6-dicarbonyl} (dialdehyde/aldehyde–ketone) embedded in the bicyclic framework. The tertiary alcohol is retained under these conditions (no oxidative removal of –OH). Step 2: Base-promoted intramolecular aldol and aromatization.
In NaOH, the 1,6-dicarbonyl undergoes intramolecular aldol cyclization. Two regioisomeric closures are possible (attack of either carbonyl), each followed by dehydration and keto–enol tautomerization to the \emph{phenolic} form. This furnishes two alkyl-substituted naphthols (positional isomers). Step 3: Final Pd/C step.
Pd/C here acts as a \emph{dehydrogenation/aromatization} catalyst to ensure full aromaticity of the newly formed ring; it does not remove the phenolic OH under these conditions. Hence, the products remain as naphthols. Conclusion: The reaction delivers two positional naphthol isomers, corresponding to options (A) and (B); options without –OH (e.g., (C)) are not consistent with the sequence.
