Why is a ketone more nucleophilic than an ester?

Question

I guess the ester is a weaker nucleophile because it does have an additional oxygen atom, unlike the ketone, that is pulling electrons from the C-O double bond towards the carbon atom (this happens vice versa too of course with the ester oxygen). This lowers the ionic character of the C-O double bond (smaller $\\delta^{+}$ and $\\delta^{-}$ charge on the carbon and oxygen atoms) and thus increases the energy of the C-O $\\pi^{*}$ bond, making it less nucleophilic. Is this correct?

Answer 1

Nucleophilicity is in some cases synonymous with basicity. This happens to be one of those cases, so you're really comparing which one acts as a stronger base, hence raising its nucleophilic properties. Esters do have an extra oxygen, which in turn raises its acidity due to resonance. Acidity/more resonance/stability are all related. Esters have more resonance structures, therefore making it a weaker base than its ketone counterpart.