Cl -> OH

[Natrix]

How difficult would it be to make 2-methyl-hydrochinone from 4-chloro-3-methylphenol (PCMC) ? PCMC is a biocide and is used against bacteria, fungi and yeast.
 
https://www.thevespiary.org/rhodium/Rhodium/hive/hiveboard/picproxie_docs/000216749-file_mlju.gif" title="View this image">

[PolytheneSam]

I saw something in a chemistry book about a Dow Chemical process for making phenol from chlorobenzene using NaOH solution at 350 degrees C under pressure.
http://www.geocities.com/dritte123/PSPF.html

[Rhodium]

Reflux in strong sodium hydroxide solution together with copper powder, for at least 24h.

A general method is described for 5-hydroxyvanillin in:

https://www.thevespiary.org/rhodium/Rhodium/chemistry/mmda.mescaline.html

If you were planning on using it for 2,5-dimethoxytoluene, I'd suggest you methylate the starting material first, for easier workup, and possibly better yields.

[Natrix]

Thanks for your answers PolytheneSam and Rhodium.  Although the yield might be low (US.P. 3,778,481), the substance is very interesting because it is sold otc and it is inexpensive. 

[foxy2]

If you have access to an ultrs sonic bath I would put the reaction in it periodically.  It should increase yeilds
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