1,2-Dibromotetrachloroethane

1,2-Dibromotetrachloroethane (DBTCE) is an organohalide with the chemical formula C2Br2Cl4. It is a crystalline solid that emits lachrymatory (tear-producing) vapours. Dibromotetrachloroethane can be used as a fungicide, flame retardant and a source for bromine in the laboratory. Because the 1,1-dibromotetrachloroethane isomer is rare, 1,2-dibromotetrachloroethane is frequently referred to as simply dibromotetrachloroethane.

Reactions and synthesis
Dibromotetrachloroethane decomposes to Tetrachloroethylene and bromine when heated. Reacted with potassium sulphide, it gives tetrachloroethylene, potassium bromide and sulphur:
 * C2Br2Cl4 + K2S -> C2Cl4 + S + 2 KBr

Dibromotetrachloroethane, when reacted with aniline at 140 to 150 °C, gives pure tetrachloroethylene.

When reacted with compounds like cyclohexene, 2,2,4-trimethylpentl-ene, 1-hexene, 1-octene, 2-methyl-1-butene and 2,2,4-trimethyl-2-pentene, it yields allylic monobromides via bromination. Dibromotetrachloroethane loses both of its bromine atoms, leaving tetrachloroethylene and hydrogen bromide.

Dibromotetrachloroethane was discovered by the Italian chemist Faustino Malaguti in 1846. Malaguti exposed a mixture of Tetrachloroethylene (then known as chloréthose) and bromine to sunlight. It was named Bromure de chloréthose ("bromide of chlorethose") after its synthesis method. Similar to Malaguti's method, modern synthesis of dibromotetrachloroethane uses bromine dissolved in carbon tetrachloride.