Dewar, James benzene structure

For alternative benzene structures, such as bicyclo[2.2.0]hexa-2,5-diene, originally reported by Sir James Dewar in 1857, as well as for a detailed historical review on benzene structures, see (a) Astruc,... 

Structures A and B are the standard representations of benzene, and the bonds are the way that Kekule described them. Structures C, D, and Eare the brainchildren of the British-American chemist Michael James Stuart Dewar, who was born in India in 1918. 

On the other hand, it is believed by some that Kekule had intuitively anticipated by some 75 years our present concept of delocalized electrons, and drew two pictures (VIlI and IX)—as we shall do, too- as a crude representation of something that neither picture alone satisfactorily represents. Rightly or wrongly, the term Kekul6 structure has come to mean a (hypothetical) molecule with alternating single and double bonds—just as the term D war benzene has come to mean a structure (II) that James Dewar devised in 1867 as an example of what benzene was not. 

To be sure, Baeyer said, what we are talking about are pictures or representations (Bilder), which must never be confused with real things themselves, but Hertz s comment applies whenever our theoretical pictures approach the unseen reality. These same considerations apply to the benzene theory. Baeyer proceeded to summarize recent research on the structure of benzene. The benzene formula proposed years earlier by James Dewar had quickly been ruled out as unable to explain the... 

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