My book reads

Sulphonation will be the most effected electrophilic aromatic substitution reaction when benzene is replaced by hexadeutrobenzene.

I am not able to figure out how. All EAS reactions proceed by formation of an arenium ion and then the loss of an $H^+$ ion to regain aromaticity so all of them should be equally effected ( textbook does not mention how they are effected). I feel the only effect should be due to difference in bond enthalpies of $C-D$ bond and $ C-H$ bond.

I came across this reaction mechanism from chemlibretexts: enter image description here The hydrogen released is taken up by the $-SO_3H^-$

Can someone explain how and in what ways the replacement of hydrogen by deuterium effects the reaction ?

  • $\begingroup$ Noting edits is not necessary. Anyone can see the edit history. $\endgroup$
    – A.K.
    Apr 4, 2019 at 15:43


Your Answer

By clicking “Post Your Answer”, you agree to our terms of service and acknowledge you have read our privacy policy.