92. Acetylene Dichloride

Nomenclature

CAS number: 540-59-0
1,2-Dichloroethene; 1,2-dichloroethylene; sym-dichloroethylene; dioform.
C2H2Cl2; mol wt 96.94.
C 24.78%, H 2.08%, Cl 73.14%.
ClCH=CHCl.

Description and references

Prepn: Bordner, US 2504919 (1950 to du Pont). Prepn of trans-form: Adler, US 2440997 (1948 to Stockholms Superfosfot Fabriks Aktiebolag). Sepn of cis- and trans-forms by fractional distillation: Wood, Dickinson, J. Am. Chem. Soc. 61, 3259 (1939); Johnsen, Fitzpatrick, Rec. Trav. Chim. 70, 823 (1951); Truce, Barney, J. Org. Chem. 27, 128 (1962). Toxicity studies: D. Gradiski et al., Eur. J. Toxicol. 7, 247 (1974); K. J. Freundt et al., Toxicology 7, 141 (1977). Review: V. L. Stevens in Kirk-Othmer Encyclopedia of Chemical Technology Vol. 5 (Wiley-Interscience, New York, 3rd ed., 1979) pp 742-745. Review of toxicology and human exposure: Toxicological Profile for 1,2-Dichloroethene (PB95-100152, 1996) 198 pp.

Properties

Liquid; ethereal, slightly acrid odor; gradually decomposed by air, light and moisture, forming HCl. d ≈1.28. bp ≈55°. Highly flammable; extremely corrosive. Insol in water. Sol in alc, ether and most other organic solvents. LD50 i.p. in mice: ≈2150 mg/kg (Gradiski).

Derivative

cis-Form.

Nomenclature

CAS number: 156-59-2

Properties

mp 81.5°. bp745 59.6°, bp760 60°. nD25 1.4435.

Derivative

trans-Form.

Nomenclature

CAS number: 156-60-5

Properties

mp 49.4°. bp745 47.2°. Noticeably subject to air oxidation. LD50 in rats (ml/kg): 1.0 orally; 60 i.p.; in mice (ml/kg): 3.2 i.p. (Freundt).

Caution

Potential symptoms of overexposure are irritation of eyes and respiratory system; CNS depression. See NIOSH Pocket Guide to Chemical Hazards (DHHS/NIOSH 97-140, 1997) p 98. See also Patty's Industrial Hygiene and Toxicology vol. 2B, G. D. Clayton, F. E. Clayton, Eds. (Wiley-Interscience, New York, 3rd ed., 1981) pp 3550-3553.

Use

Solvent for fats, phenol, camphor, etc. Intermediate in synthesis of chlorinated solvents and compounds.