Chapter 17, Problem 17.51P

Interpretation Introduction

(a)

Interpretation: The $\text{MOs}$ of cyclooctatetraene as bonding, antibonding, or nonbonding are to be labeled.

Concept introduction: The inscribed polygon method is helpful to predict whether a compound involves completely filled bonding $\text{MOs}$ or not. The all bonding $\text{MOs}$, and the $\text{HOMOs}$ of an aromatic compound are completely filled. However, the antibonding $\text{MOs}$ are completely vacant.

Interpretation Introduction

(b)

Interpretation: The arrangement of electrons in the $\text{MOs}$ of cyclooctatetraene is to be stated and an explanation for the not aromatic nature of it is to be stated.

Concept introduction: The inscribed polygon method is helpful to predict whether a compound involves completely filled bonding $\text{MOs}$ or not. The all bonding $\text{MOs}$, and the $\text{HOMOs}$ of an aromatic compound are completely filled. However, the antibonding $\text{MOs}$ are completely vacant.

Interpretation Introduction

(c)

Interpretation: The number of $\pi$ electrons that dianion of cyclooctatetraene contain is to be predicted.

Concept introduction: The inscribed polygon method is helpful to predict whether a compound involves completely filled bonding $\text{MOs}$ or not. The all bonding $\text{MOs}$, and the $\text{HOMOs}$ of an aromatic compound are completely filled. However, the antibonding $\text{MOs}$ are completely vacant.

Interpretation Introduction

(d)

Interpretation: The arrangement of $\pi$ electrons of dianion in $\text{MOs}$ is to be stated.

Concept introduction: The inscribed polygon method is helpful to predict whether a compound involves completely filled bonding $\text{MOs}$ or not. The all bonding $\text{MOs}$, and the $\text{HOMOs}$ of an aromatic compound are completely filled. However, the antibonding $\text{MOs}$ are completely vacant.

Interpretation Introduction

(e)

Interpretation: The classification of dianion as aromatic, nonaromatic, or antiaromatic is to be stated and its being so is to be explained.

Concept introduction: The inscribed polygon method is helpful to predict whether a compound involves completely filled bonding $\text{MOs}$ or not. The bonding $\text{MOs}$, and the $\left(\text{HOMOs}\right)$ of an aromatic compound are completely filled. However, the antibonding $\text{MOs}$ are completely vacant.