How Aromatic or Antiaromatic are Annulenes

Regardless of how we wish to define the resonance stabilization of the n = 6 case of benzene, it is unequivocal that this substance enjoys considerable stabilization relative to classical expectations related to acyclic and/or less unsaturated precedent. Rather than discussing the plethora of models and even greater experimental evidence that documents this aromaticity , we consider benzene itself as the paradigm. We will return to olefinic paradigms later in this section. 

More precisely, let us consider the enthalpies of reaction for the formal process 47  

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