Dichloroiodomethane (DCIM) is a trihalomethane with the chemical formula . It is a heavy, nonflammable, transparent pale yellow liquid with a chloroform-like odour.Leopold Gmelin, Henry Watts, Chloriodoform in Hand-book of Chemistry (1848), pages 337–339 DCIM is soluble in organic solvents like acetone, diethyl ether, ethanol and benzene. It decomposes in contact with air and light. It has been detected in disinfected tap water and is considered to be a contaminant.Emma Goslan, Kenneth Clive Thompson, Simon Gillespie, Disinfection By-products in Drinking Water (2015), Royal Society of Chemistry DCIM has an estimated half-life of 275 years in water. Liu, David H. F; Liptak, Bela G, Groundwater and surface water pollution, page 57
It was discovered by Georges-Simon Serullas in 1824, two years after his discovery of iodoform. Synthesis Many synthesis routes are known. Reaction of chloroform with sodium iodideDetermination of Dichloroiodomethane in Water (1996) or iodoethaneNariyoshi Kawabata, Masami Tanimoto, Shigehiro Fujiwara. Synthesis of monohalocyclopropane derivatives from olefins by the reaction with trihalomethanes and copper, Tetrahedron, 1979 gives dichloroiodomethane. Older methods include distillation of iodoform with phosphorus pentachloride or mercuric chloride. References