Iron(III) bromide is the chemical compound with the formula FeBr3. Also known as ferric bromide, this red-brown odorless compound is used as a Lewis acid catalyst in the halogenation of aromatic compounds. It reacts with water to give acidic solutions.
Structure, synthesis and basic properties
FeBr3 forms a polymeric structure featuring six-coordinate, octahedral Fe centers. Although inexpensively available commercially, FeBr3 can be prepared by treatment of iron metal with bromine:
- 2 Fe + 3 Br2 → 2 FeBr3
Above 200 °C, FeBr3 decomposes to ferrous bromide:
- 2FeBr3 → 2FeBr2 + Br2
Iron(III) chloride is considerably more stable, reflecting the greater oxidizing power of chlorine. FeI3 is not stable, as iron(III) will oxidize iodide ions.
- ^ Holleman, A. F.; Wiberg, E. "Inorganic Chemistry" Academic Press: San Diego, 2001. ISBN 0-12-352651-5.