Editing Titanium (section)

=== Halides ===
[[File:TiCl3.jpg|thumb|right|upright=0.75|Titanium(III) compounds are characteristically violet, illustrated by this aqueous solution of [[titanium trichloride]].]]
[[Titanium tetrachloride]] (titanium(IV) chloride, TiCl<sub>4</sub><ref>{{cite report |author1=Seong, S. |author2=Younossi, O. |author3=Goldsmith, B.W. |year=2009 |title=Titanium: Industrial base, price trends, and technology initiatives |publisher=Rand Corporation |isbn=978-0-8330-4575-1 |page=10 |url=https://books.google.com/books?id=tIPFfYW304IC&pg=PA10}}</ref>) is a colorless volatile liquid (commercial samples are yellowish) that, in air, hydrolyzes with spectacular emission of white clouds. Via the [[Kroll process]], TiCl<sub>4</sub> is used in the conversion of titanium ores to titanium metal. Titanium tetrachloride is also used to make titanium dioxide, e.g., for use in white paint.<ref>{{cite book |last=Johnson |first=Richard W. |year=1998 |title=The Handbook of Fluid Dynamics |publisher=Springer |pages=38–21 |isbn=978-3-540-64612-9 |url=https://books.google.com/books?id=JBTlucgGdegC}}</ref> It is widely used in [[organic chemistry]] as a [[Lewis acids and bases|Lewis acid]], for example in the [[Mukaiyama aldol condensation]].<ref>{{cite book |last=Coates |first=Robert M. |author2=Paquette, Leo A. |year=2000 |title=Handbook of Reagents for Organic Synthesis |publisher=John Wiley and Sons |page=93|isbn=978-0-470-85625-3|url=https://books.google.com/books?id=xxYjJgupBSMC}}</ref> In the [[van Arkel–de Boer process]], [[titanium tetraiodide]] (TiI<sub>4</sub>) is generated in the production of high purity titanium metal.<ref name="Greenwood1997p965">{{harvnb|Greenwood|Earnshaw|1997|p=965}}</ref>

Titanium(III) and titanium(II) also form stable chlorides. A notable example is [[titanium(III) chloride]] (TiCl<sub>3</sub>), which is used as a [[catalyst]] for production of [[polyolefin]]s (see [[Ziegler–Natta catalyst]]) and a reducing [[reagent|agent]] in organic chemistry.<ref>{{cite encyclopedia |first1=Lise-Lotte |last1=Gundersen |first2=Frode |last2=Rise |first3=Kjell |last3=Undheim |first4=José |last4=Méndez Andino |year=2007 |title=Titanium(III) Chloride |encyclopedia=[[Encyclopedia of Reagents for Organic Synthesis]] |doi=10.1002/047084289X.rt120.pub2 |isbn=978-0-471-93623-7 }}</ref>