Titanium(III) bromide
{{chembox
| Name = Titanium(III) bromide
| ImageFile =
| IUPACName = Titanium(III) bromide
| OtherNames = Titanium tribromide
Tribromotitanium
| Section1 = {{Chembox Identifiers
| ChemSpiderID_Ref = {{chemspidercite|correct|chemspider}}
| ChemSpiderID = 120705
| PubChem = 136975
| InChI = InChI=1S/3BrH.Ti/h3*1H;/q;;;+3/p-3
| InChIKey = MTAYDNKNMILFOK-UHFFFAOYSA-K
| SMILES = [Ti](Br)(Br)Br
| CASNo = 13135-31-4
| Section2 = {{Chembox Properties
| Formula = TiBr3
| MolarMass = 287.579 g/mol
| Appearance = blue-black solid
| Density =
| MeltingPtC =
| BoilingPt =
| Section7 = {{Chembox Hazards
| NFPA-H = 0
| NFPA-R = 0
| NFPA-F = 0
}}
|Section8={{Chembox Related
| OtherAnions = Titanium(III) chloride
Titanium(III) fluoride
| OtherCompounds = Titanium(IV) bromide
}}
}}
Titanium(III) bromide is the inorganic compound with the formula TiBr3. It is a blue black paramagnetic solid with a reddish reflection. It has few applications, although it is a catalyst for the polymerization of alkenes.
Production and structure
TiBr3 can be produced by heating the tetrabromide in an atmosphere of hydrogen:{{cite book |doi=10.1002/9780470132371.ch17|chapter=Titanium(III) Chloride and Titanium(III) Bromide|year=1960|last1=Sherfey|first1=J. M.|title=Inorganic Syntheses |pages=57–61|volume=6|isbn=978-0-470-13237-1}}
:2{{nbsp}}TiBr4 + H2 → 2{{nbsp}}TiBr3 + 2{{nbsp}}HBr
It can also be produced by comproportionation of titanium metal and titanium tetrabromide.{{cite book |doi=10.1002/9780470132579.ch69|title=Inorganic Syntheses|year=1989|last1=Stebler|volume=26|first1=Anton|last2=Leuenberger|first2=Bruno|last3=Güdel|first3=Hans U.| chapter=Synthesis and Crystal Growth of A 3 M 2 X 9 (A = Cs, Rb; M = Ti, V, Cr; X = Cl, Br) |pages=377–385|isbn=978-0-470-13257-9}}
:Ti + 3{{nbsp}}TiBr4 → 4{{nbsp}}TiBr3
Two polymorphs of TiBr3 are known, each exhibiting octahedral Ti centers.Troyanov, S. I.; Rybakov, V. B.; Ionov, V. M. "Preparation and crystal structure of titanium tetrabromide, titanium tribromide and titanium(2+) tetrabromoaluminate(1-)" Zhurnal Neorganicheskoi Khimii 1990, vol. 35, 882-7.
Reactions
Heating the tribromide gives titanium(II) bromide together with the volatile tetrabromide:
:2 TiBr3 → TiBr4 + TiBr2
The solid dissolves in donor solvents (L) such as pyridine and nitriles to produce 3:1 adducts:
:TiBr3 + 3 L → TiBr3L3