[Winga]

After the deprotonation of diketone then it becomes diketonate (is this term correct?).

My question is which atom has a higher tendency to abstract the proton?
O or C?

In this resonance structure, as O is more electronegative, the e- density should be higher in both O atoms in time average than that of C.
However, C is less electronegative, it is easier to donate e- to the proton than that of O.

So, which factor is dominant?


One more thing, if O abstracts the proton, an enol will be formed, and it becomes diketone again after tautomerization. (but it is not related to my question)

[sundberg]

The oxygen should definately abstract the proton as neither of the resonance structures contain a carbanion. However, if you deprotonate the deketone, wouldn't it undergo an aldol condensation?