Titanium tetrabromide

From Wikipedia, the free encyclopedia
  (Redirected from Titanium(IV) bromide)
Jump to: navigation, search
Titanium tetrabromide
Titanium tetrabromide
Ball-and-stick model of the titanium tetrabromide molecule
IUPAC name
Titanium tetrabromide
Other names
Titanium(IV) bromide
3D model (JSmol)
ECHA InfoCard 100.029.259
EC Number 232-185-0
Molar mass 367.483 g/mol
Appearance brown crystals
Density 3.25 g/cm3
Melting point 39 °C (102 °F; 312 K)
Boiling point 230 °C (446 °F; 503 K)
dissolves,then hydrolyses
Solubility in other solvents chlorocarbons, benzene
cubic, Pa3, Z = 8
0 D
Main hazards corrosive
R-phrases (outdated) 14-34
S-phrases (outdated) 26-36/37/39-45
NFPA 704
Flammability code 0: Will not burn. E.g., water Health code 3: Short exposure could cause serious temporary or residual injury. E.g., chlorine gas Reactivity code 1: Normally stable, but can become unstable at elevated temperatures and pressures. E.g., calcium Special hazards (white): no codeNFPA 704 four-colored diamond
Flash point Non-flammable
Related compounds
Other anions
Other cations
Related compounds
Except where otherwise noted, data are given for materials in their standard state (at 25 °C [77 °F], 100 kPa).
YesY verify (what is YesYN ?)
Infobox references

Titanium tetrabromide is the chemical compound with the formula TiBr4. It is the most volatile transition metal bromide. The properties of TiBr4 are an average of TiCl4 and TiI4. Some key properties of these four-coordinated Ti(IV) species are their high Lewis acidity and their high solubility in nonpolar organic solvents. TiBr4 is diamagnetic, reflecting the d0 configuration of the metal centre.[1]

Preparation and structure[edit]

This four-coordinated complex adopts a tetrahedral geometry. It can be prepared via several methods: (i) from the elements, (ii) via the reaction of TiO2 with carbon and bromine (see Kroll process), and (iii) by treatment of TiCl4 with HBr.


Titanium tetrabromide forms adducts such as TiBr4(THF)2 and [TiBr5].[2] With bulky donor ligands, such as 2-methylpyridine (2-Mepy), five-coordinated adducts form. TiBr4(2-MePy) is trigonal bipyramidal with the pyridine in the equatorial plane.[3]

TiBr4 has been used as a Lewis-acid catalyst in organic synthesis.[4]

The tetrabromide and tetrachlorides of titanium react to give a statistical mixture of the mixed tetrahalides, TiBr4−xClx (x = 0-4). The mechanism of this redistribution reaction is uncertain. One proposed pathway invokes the intermediacy of dimers.[5]


TiBr4 hydrolyzes rapidly, potentially dangerously, to release hydrogen bromide.


  1. ^ Holleman, A. F.; Wiberg, E. "Inorganic Chemistry" Academic Press: San Diego, 2001. ISBN 0-12-352651-5.
  2. ^ Colin S. Creaser & J. Alan Creighton (1975). "Pentachloro- and pentabromo-titanate(IV) ions". J. Chem. Soc., Dalton Trans. (14): 1402–1405. doi:10.1039/DT9750001402. 
  3. ^ Hensen, K.; Lemke, A.; Bolte, M. (2000). "Tetrabromo(2-methylpyridine-N)-titanate(IV)". Acta Crystallographica. C56 (12): e565–e566. doi:10.1107/S0108270100015407. 
  4. ^ B. Patterson, S. Marumoto & S. D. Rychnovsky (2003). "Titanium(IV)-Promoted Mukaiyama Aldol-Prins Cyclizations". Org. Lett. 5 (17): 3163–3166. PMID 12917007. doi:10.1021/ol035303n. 
  5. ^ S. P. Webb & M. S. Gordon (1999). "Intermolecular Self-Interactions of the Titanium Tetrahalides TiX4 (X = F, Cl, Br)". J. Am. Chem. Soc. 121 (11): 2552–2560. doi:10.1021/ja983339i.