Match List-I (organic transformation) with List-II (reagents) and choose the correct option. List-I A. $\mathrm{C}{}_6\mathrm{H}{}_6\to \mathrm{C}{}_6\mathrm{H}{}_5\mathrm{OH}$ (benzene to phenol) B. $\mathrm{CH}{}_3\mathrm{COOH}\to \mathrm{CH}{}_3\mathrm{CH}{}_2\mathrm{OH}$ C. $\mathrm{CH}{}_3\mathrm{CH}{}_2\mathrm{CH}{}_2\mathrm{OH}\to \mathrm{CH}{}_3\mathrm{CH}=\mathrm{CH}{}_2$ D. $\mathrm{C}{}_6\mathrm{H}{}_5\mathrm{CH}(\mathrm{CH}{}_3){}_2\to \mathrm{C}{}_6\mathrm{H}{}_5\mathrm{OH}$ (cumene to phenol) List-II (I) (i) Oleum; (ii) $\mathrm{NaOH}$, heat; (iii) $\mathrm{H}{}^{+}$ (II) (i) $\mathrm{O}{}_2$; (ii) $\mathrm{H}{}_2\mathrm{O}$/$\mathrm{H}{}^{+}$ (III) (i) $\mathrm{CH}{}_3\mathrm{OH}$, $\mathrm{H}{}^{+}$; (ii) $\mathrm{H}{}_2$, catalyst (IV) (i) conc. $\mathrm{H}{}_2\mathrm{SO}{}_4$, heat; (ii) $\mathrm{H}{}^{+}$/$\mathrm{H}{}_2\mathrm{O}$

Solution & Explanation

\textbf{Answer:} (B) A-II, B-III, C-IV, D-I \textbf{Solution:} A. Phenol from benzene/cumene via aerial oxidation — the cumene process uses (i) $\mathrm{O}{}_2$ then (ii) $\mathrm{H}{}_2\mathrm{O}$/$\mathrm{H}{}^{+}$, which hydrolyses cumene hydroperoxide to phenol and acetone. So A matches (II). B. Carboxylic acid to alcohol: $\mathrm{CH}{}_3\mathrm{COOH}$ is first esterified with $\mathrm{CH}{}_3\mathrm{OH}$/$\mathrm{H}{}^{+}$ and the ester is then reduced with $\mathrm{H}{}_2$/catalyst to $\mathrm{CH}{}_3\mathrm{CH}{}_2\mathrm{OH}$. So B matches (III). C. Dehydration of 1-propanol to propene needs conc. $\mathrm{H}{}_2\mathrm{SO}{}_4$, heat; the $\mathrm{H}{}^{+}$/$\mathrm{H}{}_2\mathrm{O}$ step represents the acid-catalysed mechanism. So C matches (IV). D. Phenol via the benzenesulphonic-acid route: (i) oleum (sulphonation), (ii) $\mathrm{NaOH}$, heat (alkali fusion to sodium phenoxide), (iii) $\mathrm{H}{}^{+}$ (acidification). So D matches (I). Hence A-II, B-III, C-IV, D-I.