Question

the presence of NO2 group around a carbocation _​

Answer 1

The presence of NO2 group around a carbocation makes THE CARBOCATION UNSTABLE.

But why?

• First of all, $NO_{2}$ shows high magnitude of -I (inductive) effect. This leads to pulling of bonded electrons towards itself.

• As a result, the positive charge on the carbon atom undergoes intensification.

• Whenever, there is charge intensification, there is development of $\rm ins{t}ability$ of the ion.

Thats why, carbocation will become unstable.

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• But, if the same substituent group like NO2 is attached to a carbanion, it will leads to its stability, as it will cause charge de-intensification of the negative charge over the anion.

$\star$ Hope It Helps.