Thienoacene-fused pentalenes: syntheses, structures, physical properties and applications for organic field-effect

Gaole Dai1, Jingjing Chang, Xueliang Shi

  • 1Department of Chemistry, National University of Singapore, 3 Science Drive 3, 117543 (Singapore).

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Cycloheptatriene is a neutral monocyclic unsaturated hydrocarbon that consists of an odd number of carbon atoms and an intervening sp3 carbon in the ring. The three double bonds in the ring correspond to 6 π electrons, which is a Huckel number, and therefore satisfies the criteria of 4n + 2 π electrons. However, the intervening sp3 carbon disrupts the continuous overlap of p orbitals. As a result, cycloheptatriene is not aromatic.
Removing one hydrogen from the intervening CH2 group...
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Characteristics of the diene
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