[Dalek_Jammie]

Hello,
I am working through some questions and have just got myself very confused over inductive effects. The question asks is an ester or a ketone more reactive towards nucleophiles? I know from previous reactivity work that ketone's are more reactive. Esters have an alkyl (+I inductive effect) and an oxygen (-I inductive effect) whereas ketones have two alkyl groups, nucleophiles will prefer the one with the more positive carbon. This is where I am confusing myself, surely the two electron donating groups on the ketone will makethe carbon slightly negative. And will the inductive effects on the carbon in the ester group sort of cancel out so the ester carbon is less negative than the ketone. Unfortunately I'm sure this can't be the case and somewhere I've got the wrong end of the stick. If you could please help me I would be most grateful.

Thank you

[Jorriss]

If the comparison is of a ketone and ester, the inductive effect of the ester is not the important part - it's the resonance. Consider that.

[ooosh]

Don't forget the  p-Π conjugation,which is electron-donating and more powerfull than indutive effect. The O atom acts as an electron-donating factor,also in amide N is in the same manner.