Nomenclature
CAS number: 87-56-9
2,3-Dichloro-4-oxo-2-butenoic acid; dichloromalealdehydic acid; α,β-dichloro-β-formylacrylic acid; 2,3-dichloromaleic aldehyde acid.
C
4H
2Cl
2O
3; mol wt 168.96.
C 28.43%, H 1.19%, Cl 41.97%, O 28.41%.
Description and references
Prepn from β,γ-dichloropyromucic acid and bromine
water or dil nitric acid: Hill, Jackson, Am. Chem. J. 12, 43 (1890); by heating furfural
with manganese dioxide and hydrochloric acid: Simonis, Ber. 32, 2085 (1899); Beattie et al., J. Chem. Soc. 1932, 264; Mowry, J. Am. Chem. Soc. 72, 2535 (1950); by chlorination of butyne-1,4-diol:
Dury, Angew. Chem. 72, 864 (1960).
Properties
Monoclinic prisms from ether and ligroin, mp 127°. Slightly sol
in cold water; sol in hot water; hot benzene, alc. LD50 in rats: 0.5-1.0 g/kg orally; 10-25 mg/kg i.p., Fassett in Industrial
Hygiene and Toxicology vol. II, F. A. Patty,
Ed. (Interscience, New York, 2nd ed., 1962) p 1977.Caution
Strong irritant to skin and eyes;
a potent skin sensitizer.