Thionyl bromide
Encyclopedia
Thionyl bromide is the chemical compound SOBr2. It is less stable and less widely used than its chloride analogue, thionyl chloride
. It is prepared by the action of hydrogen bromide
on thionyl chloride, a characteristic reaction where a stronger acid is converted to a weaker acid:
Thionyl bromide is used for some brominations of certain α,β-unsaturated carbonyls, and it also converts alcohol
s to alkyl bromides. Otherwise it hydrolyzes readily to release sulfur dioxide
:
. It also reacts with acetone to give a hazardous lacrymator
.
Thionyl chloride
Thionyl chloride is an inorganic compound with the formula SOCl2. It is a reactive chemical reagent used in chlorination reactions. It is a colorless, distillable liquid at room temperature and pressure that decomposes above 140 °C. Thionyl chloride is sometimes confused with sulfuryl...
. It is prepared by the action of hydrogen bromide
Hydrogen bromide
Hydrogen bromide is the diatomic molecule HBr. HBr is a gas at standard conditions. Hydrobromic acid forms upon dissolving HBr in water. Conversely, HBr can be liberated from hydrobromic acid solutions with the addition of a dehydration agent, but not by distillation. Hydrogen bromide and...
on thionyl chloride, a characteristic reaction where a stronger acid is converted to a weaker acid:
- SOCl2 + 2HBr → SOBr2 + 2HCl
Thionyl bromide is used for some brominations of certain α,β-unsaturated carbonyls, and it also converts alcohol
Alcohol
In chemistry, an alcohol is an organic compound in which the hydroxy functional group is bound to a carbon atom. In particular, this carbon center should be saturated, having single bonds to three other atoms....
s to alkyl bromides. Otherwise it hydrolyzes readily to release sulfur dioxide
Sulfur dioxide
Sulfur dioxide is the chemical compound with the formula . It is released by volcanoes and in various industrial processes. Since coal and petroleum often contain sulfur compounds, their combustion generates sulfur dioxide unless the sulfur compounds are removed before burning the fuel...
:
- SOBr2 + H2O → SO2 + 2HBr
Safety
SOBr2 hydrolyzes readily to release dangerous HBrHydrogen bromide
Hydrogen bromide is the diatomic molecule HBr. HBr is a gas at standard conditions. Hydrobromic acid forms upon dissolving HBr in water. Conversely, HBr can be liberated from hydrobromic acid solutions with the addition of a dehydration agent, but not by distillation. Hydrogen bromide and...
. It also reacts with acetone to give a hazardous lacrymator
Lachrymatory agent
Tear gas, formally known as a lachrymatory agent or lachrymator , is a non-lethal chemical weapon that stimulates the corneal nerves in the eyes to cause tears, pain, and even blindness...
.