Chapter 9.SE, Problem 54AP

Interpretation Introduction

Interpretation:

Hydrocarbon A(C₉H₁₂) absorbs 3 equivalents of H₂ in the presence of Pd/C to yield B(C₉H₁₈). A when treated with aqueous H₂SO₄ in the presence of Hg(II) gives two isomeric ketones C and D. A upon oxidation with KMnO₄ gives a mixture of acetic acid and tricarboxylic acid E. Based on these data, structures for the compounds A-D are to be given and the reactions are to be written.

Concept introduction:

The degree of unsaturation can be calculated by comparing the molecular formula of compound given with that of its parent hydrocarbon. Both alkenes and alkynes yield alkanes by adsorbing H₂ in the presence of Pd catalyst. Alkynes require two equivalents of H₂ while alkenes require one equivalent of H₂ to give alkanes. Internal alkynes will yield a mixture of isomeric ketones when treated with aqueous H₂SO₄ in the presence of mercury (II) if they are symmetrically substituted. When oxidized with KMnO₄, monosubstituted carbons in both double and triple bonds get oxidized to carboxylic acids.

To give:

Based on the data given, the structures of A-D and to write the reactions.