Chapter 17.5, Problem 12ATS

Interpretation Introduction

Interpretation:

Given dianion is whether aromatic, nonaromatic, or antiaromatic has to be predicted.

Concept Introduction:

Huckel’s rule states that based on the number of pi electrons planar, monocyclic, and conjugated polyene compounds can be classified as aromatic or anti-aromatic.

1. a) The number of $\pi$ electrons in a cyclic conjugated system is $4n$ where n is an integer, and then it is antiaromatic.
2. b) The number of $\pi$ electrons in a cyclic conjugated system is $\left(4n+2\right)$ where n is an integer, and then it is aromatic.

Non–aromatic compounds are conjugated system that does not obey Huckel’s rule. These compounds can be either not cyclic or lacks planarity.