An organic compound (A) on catalytic hydrogenation with \( \mathrm{H_2/Pt} \) gives tetralin, and on oxidation with hot alkaline \( \mathrm{KMnO_4} \) followed by acidification gives phthalic acid. Identify compound (A).
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Fused aromatic hydrocarbons like naphthalene:
\begin{itemize}
\item Give phthalic acid on strong oxidation
\item Give tetralin on partial catalytic hydrogenation
\end{itemize}
These reactions are commonly used for identification.
Step 1: Oxidation with hot alkaline \( \mathrm{KMnO_4} \) followed by acidification converts fused aromatic rings into benzene-1,2-dicarboxylic acid (phthalic acid).
This reaction is characteristic of naphthalene.
Step 2: Catalytic hydrogenation of naphthalene using \( \mathrm{H_2/Pt} \) reduces one ring to give tetralin (tetrahydronaphthalene).
Step 3: Since compound (A) satisfies both reactions, it must be naphthalene.
will undergo alkaline hydrolysis at a faster rate than 
intramolecular substitution takes place first by involving lone pair of electrons on nitrogen. 