K2S2O8 oxidation of o/m-cresol to toluhydrochinone

[psyloxy]

Patent DE81068

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preparation of hydrochinone

3kg potassium persulfate are gradually introduced Into a solution of 1.2kg phenol and 2.5kg NaOH in 75Kg H₂O. The mixture is left alone for 1 to 2 days at room temp or 40°C. After the rxn is over carbonic acid is introduced, the unreacted phenol is removed by steam distillation, the remainder is boiled with dilute HCl or H₂SO₄ and the hydrochinone extracted with Et₂O.

preparation of toluhydrochinone

If equivalent amounts of ortho- or meta-cresol are treated as above an oily residuum remains, which, when recrystallized from benzene, gives toluhydrochinone with a mp of 124°C

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