Hydrogen Peroxide → Methyl-1,4-benzoquinone

A solution of 12.4 g (100 mmol) of methylhydroquinone in 90 ml of acetic acid and 28.4 g (250 mmol) of 30% by weight aqueous hydrogen peroxide were simultaneously added dropwise to a stirred solution of 0.68 g (2.0 mmol) of iron 5,14-dihydrodibenzo[b,i]-[5,9,14,18]tetraaza[14]annulene, 2.52 g (2.0 mmol) of a 40% by weight aqueous solution of pentasodium diethylenetriaminepentaacetate and 0.5 ml of concentrated sulfuric acid in 50 ml of acetic acid at 40° C. with cooling. The mixture was then stirred for 15 min and subsequently subjected to a steam distillation. The distillate was extracted three times with a total of 400 ml of methylene chloride. The organic phase was shaken with aqueous sodium bicarbonate solution and then with water, separated from the aqueous phase, dried over magnesium sulfate, filtered and evaporated to dryness to yield 10.9 g (89%) of methylbenzoquinone in the form of a yellow powder. Melting point 69°-71° C.