Benzenes fulvene generation

On the other hand, shock waves generate high pressures as well as high temperatures, and, consequently, some factor in addition to heat must be involved in the shock reaction. Drickamer [145], for example, has suggested a close relationship between photochemistry and high-pressure chemistry. He experimentally showed that high-pressure conditions promoted the formation of pentacene dimers with cross-linked structure, the formation of which usually occurred in the photochemical reaction. If the shock reaction is a type of some reactions in excited states such as a photochemical reaction, many valence isomers such as Dewar benzene and benzvalene would be generated from benzene by shock waves, and the interaction between these isomers would produce various compounds such as derivatives of fulvene. Such valence isomers are unstable and would not have been detected in our study. 

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