Molybdocene dichloride

Molybdocene dichloride is the organomolybdenum compound with the formula (η⁵-C₅H₅)₂MoCl₂ and IUPAC name dichlorobis(η⁵-cyclopentadienyl)molybdenum(IV), and is commonly abbreviated as Cp₂MoCl₂. It is a brownish-green air- and moisture-sensitive powder. In the research laboratory, it is used to prepare many derivatives.

Molybdocene dichloride

Names
IUPAC name dichlorobis(η5-cyclopentadienyl)molybdenum(IV)
Other names molybdocene dichloride, molybdenocene dichloride, dichloridobis(cyclopentadienyl)molybdenum(IV)
Identifiers
CAS Number	12184-22-4
3D model (JSmol)	Interactive image
ChemSpider	398274
ECHA InfoCard	100.159.644
PubChem CID	452153
CompTox Dashboard (EPA)	DTXSID10923978
InChI InChI=1S/2C5H5.2ClH.Mo/c2*1-2-4-5-3-1;;;/h2*1-5H;2*1H;/q2*-1;;;+2/p-2 Key: QGGWSCVAFKWITK-UHFFFAOYSA-L InChI=1/2C5H5.2ClH.Mo/c2*1-2-4-5-3-1;;;/h2*1-5H;2*1H;/q2*-1;;;+2/p-2/r2C5H5.Cl2Mo/c2*1-2-4-5-3-1;1-3-2/h2*1-5H;/q2*-1; Key: QGGWSCVAFKWITK-OWLYHJECAX
SMILES [cH-]1cccc1.[cH-]1cccc1.Cl[Mo+2]Cl
Properties
Chemical formula	C10H10Cl2Mo
Molar mass	297.04 g·mol−1
Appearance	greenish-brown powder
Solubility in water	insoluble, moisture sensitive
Hazards
Safety data sheet (SDS)	[1]
Related compounds
Related compounds	Ferrocene Zirconocene dichloride Vanadocene dichloride Niobocene dichloride Titanocene dichloride Tantalocene dichloride
Except where otherwise noted, data are given for materials in their standard state (at 25 °C [77 °F], 100 kPa). Infobox references

Preparation and structure

The compound is prepared from molybdocene dihydride by treatment with chloroform:^[2]

(C₅H₅)₂MoH₂ + 2 CHCl₃ → (C₅H₅)₂MoCl₂ + 2 CH₂Cl₂

The compound adopts a "clamshell" structure where the Cp rings are not parallel, the average Cp(centroid)-M-Cp angle being 130.6°. The two chloride ligands are cis, the Cl-Mo-Cl angle of 82° being narrower than in niobocene dichloride (85.6°), which in turn is less than in zirconacene dichloride (92.1°). This trend helped to establish the orientation of the HOMO in this class of complex.^[3]

Uses

Unlike the titanocene and zirconacene derivatives, the molybdocene compounds have yielded no commercial applications.

All metallocene dihalides exhibit some anti-cancer activity,^[4] but these have not yielded useful compounds in the clinic.^[5]