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A phenanthrene derivative with a terminal vinyl (CH=CH2) side chain undergoes four separate transformations: (i) the double bond is reduced to give an ethyl group; (ii) the double bond is epoxidized; (iii) the double bond is converted to a vicinal diol; (iv) the terminal alkene is oxidized to a methyl ketone (Wacker-type). Identify the correct reagent set.

1. (i) H2/Pt; (ii) MCPBA; (iii) Cold alk. KMnO4; (iv) O2 + PdCl2 + CuCl2 + H2O
2. (i) H2/Pd + BaSO4 + quinoline; (ii) HCO3H; (iii) Hot alk. KMnO4; (iv) dil. H2SO4 + Hg2+
3. (i) Sia2BH + CH3COOH; (ii) PhCO3H; (iii) OsO4/NaHSO3; (iv) O2 + PdCl2 + CuCl2 + H2O
4. (i) BH3 + THF + CH3COOH; (ii) MCPBA; (iii) OsO4/H2O; (iv) O2 + PdCl2 + CuCl2 + H2O

Correct answer: (i) H2/Pt; (ii) MCPBA; (iii) Cold alk. KMnO4; (iv) O2 + PdCl2 + CuCl2 + H2O

Solution

Only option A has H2/Pt for (i) (direct hydrogenation to ethyl group) + MCPBA for (ii) + cold KMnO4 for (iii) (syn-diol) + Wacker for (iv). Option D uses BH3 (gives alcohol), option B uses hot KMnO4 (cleaves diol/alkene, not just diol).

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