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Xantphos

Xantphos


IUPAC name	4,5-Bis(diphenylphosphino)-9,9-dimethylxanthene
Other names	Xantphos
Identifiers
CAS number	161265-03-8
PubChem	24889800
Properties
Molecular formula	C₃₉H₃₂OP₂
Molar mass	578.62 g/mol
Appearance	colourless solid
Density	1.34 g/mL
Melting point	224-228 °C
Solubility in water	organic solvents
Hazards
Main hazards	flammable
Except where noted otherwise, data are given for materials in their standard state (at 25 °C, 100 kPa) Infobox disclaimer and references

Xantphos is an organophosphorus compound derived from the heterocycle xanthene. It is used as a bidentate ligand and is noteworthy for having a particularly wide bite angle. Such ligands are useful in the hydroformylation of alkenes.^[1] Illustrative of its wide bite angle, it forms both cis and trans adducts of platinum(II) chloride.

The ligand is prepared by di-lithiation of 9,9-dimethylxanthene with sec-butyllithium followed by treatment with chlorodiphenylphosphine.^[2]

References

^ Piet W. N. M. van Leeuwen, Paul C. J. Kamer, Joost N. H. Reek, and Peter Dierkes (2000). "Ligand Bite Angle Effects in Metal-catalyzed C-C Bond Formation". Chemical Reviews 100: 2741-2769. doi:10.1021/cr9902704.
^ Mirko Kranenburg, Yuri E. M. van der Burgt, Paul C. J. Kamer, Piet W. N. M. van Leeuwen, Kees Goubitz, and Jan Fraanje (1995). "New Diphosphine Ligands Based on Heterocyclic Aromatics Inducing Very High Regioselectivity in Rhodium-Catalyzed Hydroformylation: Effect of the Bite Angle". Organometallics 14: 3081 - 3089. doi:10.1021/om00006a057.