Why ketone does not exhibit in Electrophillic substitution Rxn?

1.	Why ketone does not exhibit in Electrophillic substitution Rxn?
Answer» Because carbonyl groups are strongly polarized: partially positive at the carbon end, partially negative at the oxygen end. The result is that the oxygen end is a (rather weak) Bronsted base, while the carbon end is attractive to nucleophiles. You should notice that only anionic nucleophiles add to neutral carbonyl groups, because the product of addition is a negative charge on oxygen. In order to add a neutral nucleophile, you need to protonate the oxygen first.

Answer»

Because carbonyl groups are strongly polarized: partially positive at the carbon end, partially negative at the oxygen end.

The result is that the oxygen end is a (rather weak) Bronsted base, while the carbon end is attractive to nucleophiles.

You should notice that only anionic nucleophiles add to neutral carbonyl groups, because the product of addition is a negative charge on oxygen.

In order to add a neutral nucleophile, you need to protonate the oxygen first.

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