Sciencemadness Discussion Board

Synthesis of pyrocathecol and hydroquinone from benzene

Vanry - 15-12-2017 at 01:15

Hi !

Everything is in the title. Based on some books, my original idea was:

Benzene + H2SO4 -> benzenesulfonic acid

Benzenesulfonik acid + NaOH -(heat)-> phenol

Phenol + H2O2(35%) -(some catalyst ?)-> cathecol + hydroquinone

Does it seem viable to you ? Did anybody had an idea on the catalyst for the last step ? I have read somewhere that copper and iron sulfate can be used to selectively made those two and enhance the final yield.

Thank you in advance for your answers ;)

Chemi Pharma - 15-12-2017 at 11:38

To hydroxylate phenol to cathecol and hydroquinone you will need a chelating agent formed by the mixture of a transition metal salt and an organic ligant compound, as a catalyzer, to get the reaction between phenol and hydrogen peroxyde runs.

I'm attaching a Patent below that describes the answer to your question.

Further, I attached another patent describing how to separate the mixture of cathecol and hydroquinone you've obtained following the lines above in each one of the pure products.

Enjoy it.

Attachment: Catechol and Hidroquinone from phenol.pdf (476kB)
This file has been downloaded 362 times

Attachment: Catechol and Hidroquinone separation.pdf (1.3MB)
This file has been downloaded 323 times

[Edited on 15-12-2017 by Chemi Pharma]

Vanry - 16-12-2017 at 07:21

Thank you a lot !
I didn’t expected so much in such a short time :)

May I be a bit more insisting by asking were you find that ?

Chemi Pharma - 16-12-2017 at 10:00

I have a large collection of studies, patents, chemical journals and bulletins on the hand.

Some data I searched at the NET, some I caught with other sciencemadness community friends and another chemical foruns.

The most important is you know that here, at Sciencemadness, you can always find a friendly answer to your questions.

You're welcome here. Cheers!;)

Vanry - 26-12-2017 at 10:58

Just have some more questions:

For the first part with the sulfonation, it appears to be a well known reaction and i was wondering if someone got some precise idea on the steps/yield.
Same thing for the hydrolysis ^^

I read here:
http://www.sciencemadness.org/smwiki/index.php/Phenol
that it can also be made from chlorobenzene.

what is the most viable/hight yield way ?


thx for reading and answers