Why nucleophilic substitution reaction do not take place in aryl halide and alkyl halide

Asked by priadkonkar | 21st Jan, 2019, 08:52: PM

Expert Answer:

There is an interaction between one of the lone pairs on the halogen atom and the π electrons of the ring, and this strengthens the bond.

So it is difficult to break the bond.

The electron-withdrawing polar effect of the ring double bonds destabilises an aryl cation.

They require very high energy for the formation of carbocation intermediate -aryl cation.

Thus making SN1 reactions impossible.

Answered by Varsha | 21st Jan, 2019, 10:01: PM