Chapter 11, Problem 33P

Interpretation Introduction

Interpretation:

Structural formulas for all the conjugated, isolated, and cumulated dienes that give $2,4-dimethylpentane$ on catalytic hydrogenation are to be written.

Concept introduction:

Catalytic hydrogenation is the addition of two atoms of hydrogen to a double bond. A compound with two double bonds undergoes catalytic hydrogenation, then there will be addition of four atoms of hydrogen.

This reaction occurs in the presence of platinum, palladium, nickel, or rhodium. One molar equivalent of hydrogen, when added to alkene, yields the corresponding alkane while two molar equivalents, when added to a compound with two double bonds OR a triple bond, yield corresponding alkane.

Conjugated dienes contain two $C=C$ units joined by a single bond that can be represented by $C=C-C=C$.

Isolated dienes contain two $C=C$ units separated by one or more $s{p}^3$ carbon atoms.

Cumulated dienes contain two $C=C$ units sharing a single carbon that can be represented by $C=C=C$.