Получение толугидрохинона.

p-Alkyl nitro aromatic compds. are reduced with powd. Al and aq. acid
(H2SO4, H3PO4, HCl, (CO2H)2, or RSO3H) to the corresponding alkyl hydroquinones;
the alkyl chain may be up to 4 C atoms in lenght. Reduction at elevated temp.
yields the corresponding alkyl p-aminophenols obtained in mixt. with the
hydroquinones. Addn. of 7.5g Al flakes [Osmium bets turnings or his favorite
sheet will work] over 1.5-2.0 hrs. at 95° to 17.5g p-nitrotoluene in 37.5 ml. H2SO4 (d. 1.85) and 500ml.
H2O, filtration, and steam distillation gave a little (p-MeC6H4)2NH, m.78-9°;
extn. with Et2O gave 4.5g 1,2,5-MeC6H3(OH)2 [toluhydroquinone], m. 125° (from
petr. ether); addition of Na2SO3 and Na2CO3 until the soln was alkaline,
filtration, treatment with Et2O and EtOH and concentration of the organic
extracts gave 0.65g p-toluidine, m. 44°.

A similar reaction with a smaller amt. of Al gave some p-cresol in addn. to the above
products. p-O2N-C6H4-Et similarly gave ethylhydroquinone. Similarly, p-PrC6H4-NO2
yields propylhydroquinone, m. 89-90C°C. p-BuC6H4-NO2 similarly yields butylhydroquinone,
m. 86.5-87.0°C The Al flakes may be conveniently added to a mixt. of the NO2 compd.and
aq. acid.

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