Titanocene dichloride

Titanocene dichloride

Names
IUPAC name Dichloridobis(η5-cyclopentadienyl)titanium
Other names titanocene dichloride, dichlorobis(cyclopentadienyl)titanium(IV)
Identifiers
CAS Number	1271-19-8 Y
3D model (Jmol)	Interactive image
ChemSpider	34981141 N
ECHA InfoCard	100.013.669
PubChem CID	5284468
RTECS number	XR2050000
InChI InChI=1S/2C5H5.2ClH.Ti/c2*1-2-4-5-3-1;;;/h2*1-5H;2*1H;/q2*-1;;;+4/p-2 N Key: YMNCCEXICREQQV-UHFFFAOYSA-L N InChI=1/2C5H5.2ClH.Ti/c2*1-2-4-5-3-1;;;/h2*1-5H;2*1H;/q2*-1;;;+4/p-2/r2C5H5.Cl2Ti/c2*1-2-4-5-3-1;1-3-2/h2*1-5H;/q2*-1;+2 Key: YMNCCEXICREQQV-JUFMQDBHAK
SMILES [cH-]1cccc1.[cH-]1cccc1.Cl[Ti+2]Cl
Properties
Chemical formula	C10H10Cl2Ti
Molar mass	248.96 g/mol
Appearance	bright red solid
Density	1.60 g/cm3, solid
Melting point	289 °C (552 °F; 562 K)
Solubility in water	sl. sol. with hydrolysis
Structure
Crystal structure	Triclinic
Coordination geometry	Dist. tetrahedral
Hazards
R-phrases	R37, R38
S-phrases	S36
NFPA 704	2 1
Related compounds
Related compounds	Ferrocene Zirconocene dichloride Hafnocene dichloride Vanadocene dichloride Niobocene dichloride Tantalocene dichloride Molybdocene dichloride Tungstenocene dichloride TiCl4
Except where otherwise noted, data are given for materials in their standard state (at 25 °C [77 °F], 100 kPa).
N  (what is YN ?)
Infobox references

Titanocene dichloride is the organotitanium compound with the formula (η⁵-C₅H₅)₂TiCl₂, commonly abbreviated as Cp₂TiCl₂. This metallocene is a common reagent in organometallic and organic synthesis. It exists as a bright red solid that slowly hydrolyzes in air. Cp₂TiCl₂ does not adopt the typical "sandwich" structure like ferrocene due to the 4 ligands around the metal centre, but rather takes on a distorted tetrahedral shape. It shows antitumour activity and was the first non-platinum complex to undergo clinical trials as a chemotherapy drug.

Cp₂TiCl₂ continues to be prepared from titanium tetrachloride, in the same way as its original synthesis by Wilkinson and Birmingham:

The reaction is conducted in THF. Workup sometimes washing with hydrochloric acid to convert hydrolysis derivatives to the dichloride. Recrystallization from toluene forms acicular crystals.

Cp₂TiCl₂ can also be prepared by using freshly distilled cyclopentadiene:

This reaction is conducted under a nitrogen atmosphere and by using THF as solvent. The product is purified by soxhlet extraction using toluene as solvent.

The complex is pseudotetrahedral. Each of the two Cp rings are attached as η⁵ ligands. Viewing the Cp ligands as tridentate, the complex has a coordination number of 8.