2078. Chloranil

Nomenclature

CAS number: 118-75-2
2,3,5,6-Tetrachloro-2,5-cyclohexadiene-1,4-dione; 2,3,5,6-tetrachloro-p-benzoquinone; tetrachloroquinone; Spergon; Vulklor.
C6Cl4O2; mol wt 245.88.
C 29.31%, Cl 57.68%, O 13.01%.

Description and references

Prepd from p-phenylenediamine or phenol by treating with KClO3 and HCl. Because of its great resistance to further oxidation, chloranil is formed as the final product of the chlorate-HCl oxidation of many aromatic compds. For comprehensive list see Huntress, Organic Chlorine Compounds (New York, 1948). Laboratory procedure starting with phenol or p-chlorophenol: Fierz-David, Blangey, Grundlegende Operationen der Farbenchemie (Vienna, 5th ed., 1943) p 140. Use as reagent for pamaquine, q.v., in urine: Schulemann et al., Chem. Zentralbl. 1928, I, 2193. Aqueous decomposition study: D. H. Sarr et al., Environ. Sci. Technol. 29, 2735 (1995). Review: Health and Environmental Effects Profile for Chloranil (EPA PB88-219696, 1986) 59 pp.

Chemical structure

Properties

Golden-yellow platelets from acetic acid or acetone. Monoclinic prisms from benzene or toluene or by sublimation in vacuo, mp 290°. Absorption spectrum in chloroform: Lifschitz et al., Rec. Trav. Chim. 43, 276, 658 (1924). Insol in water; almost insol in cold petr ether, cold alcohol. Sol in ether; sparingly sol in chloroform, carbon tetrachloride, carbon disulfide. Solubility data: Dimroth, Bamberger, Ann. 438, 103, 106 (1924).

Caution

Potential symptoms of overexposure are watery diarrhea, CNS depression, coma. Not absorbed percutaneously; direct contact may cause skin irritation. See Clinical Toxicology of Commercial Products, R. E. Gosselin et al., Eds. (Williams & Wilkins, Baltimore, 5th ed., 1984) p II-317.

Use

Agricultural fungicide, dye intermediate, reagent. Manuf of electrodes for pH measurement.