What does this representation of organic aromatic compounds mean? I saw this structure in some problem. What does this mean? How to express this in form of a simple structure
This is the cyclooctatetraene dianion. One way to get to it is to start with cyclooctatriene and remove one hydrogen ion each from the two $\ce{- CH2 -}$ groups. This is related to the cyclopentadienyl anion, the more common aromatic anion.

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