Dichloroethyne Chemical Properties
- Melting point:
- refractive index
- 3 (Vol. 39, Sup 7, 71) 1999
- EPA Substance Registry System
- Dichloroacetylene (7572-29-4)
Dichloroethyne Usage And Synthesis
DCA is a volatile, pyrophoric oil. It has an unpleasant, sweetish odor. A gas above 32°C/90°F.
DCA is not commercially available in large quantities. It is reportedly a by-product of the synthesis of vinylidene chloride and is not known to be used commercially.
By-product in synthesis of vinylidene chloride; decomposition product of trichloroethylene under alkaline conditions
DCA is a highly toxic, spontaneously combustible, undesired, and noncommercial product of the dehydrochlorination of trichloroethylene. It has resulted from exposure of trichloroethylene vapor to Hopcalite in a closed environmental system (submarine) and soda lime in closed circuit (rebreathing) anesthesia machines and from exposure of trichloroethylene liquid to caustic in degreaser tanks. It may also be an undesired by-product during chemical processes such as production of vinylidene chloride. When DCA was decomposed in the presence of oxygen, seven substanceswere found: phosgene, hexachlorobutadiene, chloroform, carbon tetrachloride, trichloroacetyl chloride, tetrachloroethylene, and trichloroacryloyl chloride.
The Journal of Organic Chemistry, 52, p. 3461, 1987 DOI: 10.1021/jo00391a059
Volatile oil with a disagreeable, sweetish odor. Mp: -68 to -65°C; bp: 32-34°C. Density: 1.38 g cm-3. Is not produced commercially.
Air & Water Reactions
Ignites or explodes upon contact with air (MCA Case History 1989 (1974)).
Dichloroethyne is a reducing agent. Incompatible with oxidizing agents. Can ignite or explode on contact with air or if heated. Can explode if shocked. Burns in the presence of chlorine to form phosgene (Ann. Chem. 640:5(1961)).
Dichloroacetylene is a neurotoxin; it is carcinogenic in experimental animals.
Confirmed carcinogen with experimental carcinogenic data. Poison by inhalation. Central nervous system effects. Can be formed by thermal decomposition (>70摄氏度) from trichloroethylene. Symptoms include a disabling nausea and intense jaw pain. Strong explosive when shocked or exposed to heat or air. Can react vigorously with oxidizing materials. When heated to decomposition or on contact with acid or acid fumes it emits highly toxic fumes of Cl-. See also ACETYLENE COMPOUNDS and CHLORINATED HYDROCARBONS , ALIPHATIC.
DCA, dichloroacetylene, is not produced commercially and is a possible decomposition product of trichloroethylene or trichloroethane. Reported to be a by-product of vinylidene chloride (see V:0220). Also, a closed circuit anesthesia with trichloroethylene, heat and moisture produced by soda-lime absorption of CO2 may produce dichloroacetylene (DCA) along with phosgene and carbon monoxide (CO).
The IARC concluded that there is limited evidence for the carcinogenicity of DCA to experimental animals based on treatment-related increases in the incidence of adenocarcinomas of the kidney in male mice, benign tumors of the liver and kidney, and an increased incidence of lymphomas in rats.
By the incubation of dichloroacetylene with rat liver and kidney subcellular fractions, the formation of S- (1,2-dichlorovinyl)glutathione (DCVG) is observed, and N-acetyl-S-(1,2-dichlorovinyl)-L-cysteine is identified as a urinary metabolite in rats.
Explosive! Dichloroacetylene is cited by DOT as “FORBIDDEN.”
An unstable explosive; heat or shock may cause explosion. Incompatible with oxidizers (chlorates, nitrates, peroxides, permanganates, perchlorates, chlorine, bromine, fluorine, etc.); contact may cause fires or explosions. Keep away from alkaline materials, strong acids (forms poisonous gases of phosgene and hydrogen chloride), strong bases.
- Sulfur hexafluoride
- lithium chloroacetylide
- sodium chloroacetylide
- VINYL CHLORIDE
- N-PHENYL-1-NAPHTHYLAMINE HYDROBROMIDE, 98
- acetylene bromide