Chapter 19, Problem 19.37P

Interpretation Introduction

(a)

Interpretation:

Whether umpolung (polarity reversal) should be considered to join the highlighted carbons together in the given pair of molecules is to be determined.

Concept introduction:

To form a bond between two atoms, one atom must carry partial or full negative charge (i.e. nucleophile) and another must carry partial or full positive charge (i.e. electrophile). If both atoms which are expected to form a bond carry similar charge, then the charge of one of the atom can be reversed and the polarity of that atom can be inverted. This concept of polarity inversion is called umpolung, where the reactivity/polarity of one of the atom in the molecule can be reversed.

Interpretation Introduction

(b)

Interpretation:

Whether umpolung (polarity reversal) should be considered to join the highlighted carbons together in the given pair of molecules is to be determined.

Concept introduction:

To form a bond between two atoms, one atom must carry partial or full negative charge (i.e. nucleophile) and another must carry partial or full positive charge (i.e. electrophile). If both atoms which are expected to form a bond carry similar charge, then the charge of one of the atom can be reversed, and the polarity of that atom can be inverted. This concept of polarity inversion is called umpolung, where the reactivity/polarity of one the atom in the molecule can be reversed.

Interpretation Introduction

(c)

Interpretation:

Whether umpolung (polarity reversal) should be considered to join the highlighted carbons together in the given pair of molecules is to be determined.

Concept introduction:

To form a bond between two atoms, one atom must carry partial or full negative charge (i.e. nucleophile) and another must carry partial or full positive charge (i.e. electrophile). If both atoms which are expected to form a bond carry similar charge, then the charge of one of the atom can be reversed, and the polarity of that atom can be inverted. This concept of polarity inversion is called umpolung, where the reactivity/polarity of one the atom in the molecule can be reversed.