8074. Quinone

Nomenclature

CAS number: 106-51-4
2,5-Cyclohexadiene-1,4-dione; p-quinone; 1,4-benzoquinone; 1,4-cyclohexadienedione.
C6H4O2; mol wt 108.09.
C 66.67%, H 3.73%, O 29.60%.

Description and references

Made by oxidation of aniline with sodium dichromate in presence of sulfuric acid. Laboratory prepn from hydroquinone: Vliet, Org. Synth. 2, 85 (1922); also Org. Synth. coll. vol. I (2nd ed., 1941). Cf. Underwood, Walsh, ibid. 16, 73 (1936). Toxicity study: Woodard et al., Fed. Proc. 8, 348 (1949).

Chemical structure

Properties

Yellow monoclinic prisms from water or petr ether. Penetrating odor resembling that of chlorine. Irritating vapors. d420 1.318. mp 115.7°. Sublimes [sublimation velocities in vacuo: Kempf, J. Prakt. Chem. [2] 78, 236 (1908)]. Volatile with steam. Absorption spectrum: Hantzsch, Ber. 49, 522 (1916). Dipole moment: 0.67. Polemic over correct values: Paoloni, J. Am. Chem. Soc. 80, 3879 (1958). Slightly sol in water; sol in alcohol, ether, hot petr ether, alkalies. LD50 orally in rats: 130 mg/kg (Woodard).

Caution

Potential symptoms of overexposure are eye and skin irritation, conjunctivitis; keratitis. See NIOSH Pocket Guide to Chemical Hazards (DHHS/NIOSH 97-140, 1997) p 272.

Use

Oxidizing agent; in photography; manuf dyes; manuf hydroquinone; tanning hides; making gelatin insol; strengthening animal fibers; as reagent.