What resonance forms stabilize deprotonated hydroquinone?
Deprotonated hydroquinone looks like this:
Possible resonance forms include:
1 and 2 look reasonable: they don't carry multiple charges. My question is: how much do these two structures contribute to the stability of deprotonated hydroquinone? I am thinking that they should be much higher energy than the structure on top, because the negative charge is on C, which is not nearly as electronegative as O.
Can this be quantified (by and for amateur chemists)?
Per Michael Lautman's suggestion, here are partial charges as calculated in Avogadro:
The pattern expected from the resonance forms above, with more negative charge on carbons 2, 4, and 6, is not there.
Why is C4 -0.20?
For comparison, deprotonated cyclohexane-1,4-diol: