In This Chapter
Seeing what makes aromatics so darn stable
Making molecular orbital diagrams for ring systems
Distinguishing aromatic, anti-aromatic, and non-aromatic rings
Naming aromatic compounds
According to organic legend, the structure of the parent aromatic system, benzene, came to the chemist August Kekulé in a dream. For a long time the structure of benzene — a liquid isolated from a tarry residue from burning petroleum gas — had eluded chemists, and many structures for the compound had been proposed by big names in the field. Kekulé claimed that in a dream he saw a snake devouring its own tail, forming a circle. Benzene must be a ring, he thought when he awoke, and jotted down the correct structure of the compound (or so he claimed, somewhat dubiously, many years later). Kekulé’s intuition about the cyclic structure of benzene was correct, and soon led to the discovery of aromatic rings other than benzene.
Benzene and other aromatics are a highly interesting class of ringed compounds of exceptional stability. In this chapter, ...