Benzene

Benzene is a special compound. It represents carbon in a six-atom cyclic chain, with the formula C₆H₆. This is a problem. Normally you might try to draw C₆H₆ as

This would be cyclo-hexa-1,3,5-triene. Unfortunately, evidence suggests that the six bonds are identical; sort of one-and-a-half bonds between each carbon pair. Also, modelling cyclohexane always leads to a molecule with a bent shape, while benzene has a flat ring. This also leads to the following question: what is the name of this compound?

[Mercedes Benzene. As a matter of fact, the Benz in Mercedes Benz and the benz in benzene ARE both named for a German scientist, Karl Benz.]

All of which leads to another story of Chemical serendipity. The tale is told of one Friedrich August Kekulé, yet another German chemist, who had all this evidence about benzene at hand, but couldn’t figure out a structure by which to explain it all. One evening, while riding the bus home, he fell to daydreaming, and his mind was filled with visions of carbon atoms dancing around. Whether today this would qualify him as a genius or a candidate for an institution is unclear, but that he was able to get from there to the structure of benzene, and indeed organic chemistry in general, in his time, made his career.