Nucleophilic aromatic substitution requires a proper nucleophile which displaces a good leaving group. The hydroxyl group is categorized as a bad leaving group so there is need to transform it into a good one by protonation or other means.

To start with, please see the Wikipedia:

https://en.wikipedia.org/wiki/Nucleophilic_aromatic_substitution

Nucleophilic substitution reaction is not easily taken place in aromatic compounds because of resonance aromatic ring behaves as nucleophile. There must be a labile group so that reaction may possible.

Dear Amresh Baitha ,

So if i have sulfonic group in my ring at ortho position,What will be the best reagent to replace sulfonic group into hydroxyl group according to you??

kindly please suggest!

Initially treat it with caustic soda then hydrochloric acid

Thankyou Amresh Baitha And One last question is that if i carry out fusion with caustic soda (as you are suggesting) then at how much temprature and conditions???

kindly suggest ???

Temp should be high ( between 300-400°C)

Thankyou soo much Amresh Baitha

Convert OH group into OSO2CF3 by reaction with Tf2O. Triflat anion is a good leaving group and nucleophilic substitution will take place, may be easyly like as with a halogen as a leaving group

Dear Kirill I. Petko ,

Thankyou for your valuable opinion!

Basically, I am trying to displace sulfonic group HSO3 in a aromatic ring by hydroxyl group!

any suggestion???

Not sure you can do it in one step, but it's certainly do-able. Heating in the presense of water will remove/reduce the sulfonyl group to a H. You can then nitrate this position with cold HNO3/H2SO4, assuming you have proper directing group. Reduction with HCl/Zn or even H2/Pd will give you an amino group which you can convert to a diazonium ion w NaNO2/HCl. Adding this slowly into boiling water will replace the N with a hydroxyl group.

But if you wanted a phenol in the first place, it would have been easier to just start with a protected version of this (methoxy, benzoxy) instead of a sulfonyl group.

Thankyou Nick Drapela !

i will surely try this !

one last question is that can i induce hydroxyl group in benzene By oxidation of benzene through hydrogen per oxide H2O2?if yes ? How can i do it??

Please suggest?

Halogenate first then heat with aq. NaOH or KOH.

It may help you

There no possibility of nucleophilic aromatic substitution of hydroxyl group without the presence of sulfonic group as OH is not a better leaving group.