1,2-Dibromotetrachloroethane
1,2-Dibromotetrachloroethane is an organohalide with the chemical formula. It is a crystalline solid that emits lachrymatory 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:Dibromotetrachloroethane, when reacted with aniline at 140 to 150 °C, gives pure tetrachloroethylene.
When reacted with compounds like cyclohexene, 2,2,4-trimethylpentene, 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 and bromine to sunlight. It was named Bromure de chloréthose after its synthesis method. Similar to Malaguti's method, modern synthesis of dibromotetrachloroethane uses bromine dissolved in carbon tetrachloride on tetrachloroethylene.