Chemical Properties
A dark grey to brownish-black crystalline mass that can be dissolved in ethanol, ether, chloroform, carbon disulphide, and other solvents. When it is heated, it becomes partially dissociated. It can prepared by the action of iodine with bromine in a stream of nitrogen. It is used in organic synthesis.
Uses
Iodine monobromide is used as an electrophile employed in a new synthetic approach to polyketide structural units. It is also used in iodometry and serves as a source of I+. It is a powerful iodinating agent used in organic synthesis as well as involved in the synthesis of radioiodinated fatty acids for heart imaging.
Preparation
Prepared from the elements, excess Br is removed by heating to 50 °C in a current of CO2.
Hazard
Toxic by ingestion and inhalation, vapors
corrosive to tissue.
Health Hazard
Vapors of iodine monobromide are irritatingto the skin, eyes, and mucous membranes.Its concentrated solutions are corrosive to theskin. Toxicity data for this compound are notavailable.
Fire Hazard
Noncombustible solid. The molten salt ex plodes when mixed with potassium, and
ignites with finely divided aluminum. Its
mixture with sodium explodes on impact.
The reaction of phosphorus with molten salt
is violent.
Purification Methods
The brown-black crystals are purified by repeated fractional crystallisation from its melt. The vapour dissociates on heating [Yost et al. J Amer Chem Soc 55 552 1933, Schmeisser in Handbook of Preparative Inorganic Chemistry (Ed. Brauer) Academic Press Vol I pp 291-292 1963].
Precautions
corrosive solid and vapor; readily absorbed through skin and mucous membranes; use in a fume hood and wear gloves and appropriate protective clothing; air-, moisture-, and light-sensitive; should be stored refrigerated (under N2) in a tightly sealed amber bottle. Forms explosive mixtures with potassium and sodium, and reacts extremely exothermically with phosphorus and tin.
