Chapter 10, Problem 45P

Interpretation Introduction

(a)

Interpretation: The structure of stereoisomer that has higher melting point than eleostearic acid is to be drawn.

Concept introduction: Fatty acids are of two types: saturated fatty acid and unsaturated fatty acid. In Saturated fatty acid, double bond is absent, whereas unsaturated fatty acid consists of one or more than one double bond. The melting point of a fatty acid indirectly depends upon the number of double bond present in an acid. Higher is the number of double bonds in acid, lower will be the melting point of an acid.

When two higher priority groups are present on the opposite side then it is an $E$ isomer, whereas when two higher priority groups are present on the same side then it is an $Z$ isomer.

Interpretation Introduction

(b)

Interpretation: The structure of stereoisomer that has lower melting point is to be drawn.

Concept introduction: Fatty acids are of two types: saturated fatty acid and unsaturated fatty acid. In Saturated fatty acid, double bond is absent, whereas unsaturated fatty acid consists of one or more than one double bond. The melting point of a fatty acid indirectly depends upon the number of double bond present in an acid. Higher is the number of double bonds in acid, lower will be the melting point of an acid.

When two higher priority groups are present on the opposite side, then it is an $E$ isomer, whereas when two higher priority groups are present on the same side, then it is an $Z$ isomer.