Xantphos

Xantphos is an organophosphorus compound derived from the heterocycle xanthene. It is used as a bidentate diphosphine ligand and is noteworthy for having a particularly wide bite angle (108°).[1]. Such ligands are useful in the hydroformylation of alkenes.[2] Illustrative of its wide bite angle, it forms both cis and trans adducts of platinum(II) chloride. In the latter context, xantphos is classified as a trans-spanning ligand. A related bidentate ligand with a greater bite angle is spanphos.

Xantphos

Names
IUPAC name 4,5-Bis(diphenylphosphino)-9,9-dimethylxanthene
Other names Xantphos
Identifiers
CAS Number	161265-03-8^Y
3D model (JSmol)	Interactive image
ChemSpider	551930^Y
ECHA InfoCard	100.118.008
PubChem CID	636044
UNII	NMU72MOG9B^Y
CompTox Dashboard (EPA)	DTXSID20348350
InChI InChI=1S/C39H32OP2/c1-39(2)33-25-15-27-35(41(29-17-7-3-8-18-29)30-19-9-4-10-20-30)37(33)40-38-34(39)26-16-28-36(38)42(31-21-11-5-12-22-31)32-23-13-6-14-24-32/h3-28H,1-2H3^Y Key: CXNIUSPIQKWYAI-UHFFFAOYSA-N^Y InChI=1/C39H32OP2/c1-39(2)33-25-15-27-35(41(29-17-7-3-8-18-29)30-19-9-4-10-20-30)37(33)40-38-34(39)26-16-28-36(38)42(31-21-11-5-12-22-31)32-23-13-6-14-24-32/h3-28H,1-2H3 Key: CXNIUSPIQKWYAI-UHFFFAOYAQ
SMILES O6c1c(cccc1P(c2ccccc2)c3ccccc3)C(c7cccc(P(c4ccccc4)c5ccccc5)c67)(C)C
Properties
Chemical formula	C39H32OP2
Molar mass	578.62 g/mol
Appearance	colorless solid
Density	1.34 g/mL
Melting point	224 to 228 °C (435 to 442 °F; 497 to 501 K)
Solubility in water	organic solvents
Hazards
Main hazards	flammable
Except where otherwise noted, data are given for materials in their standard state (at 25 °C [77 °F], 100 kPa).
N verify (what is ^YN ?)
Infobox references

Not to be confused with XPhos.

The ligand is prepared by double directed lithiation of 9,9-dimethylxanthene with sec-butyllithium followed by treatment with chlorodiphenylphosphine.[3]

References

1. Birkholz, Mandy-Nicole; Freixa, Zoraida; van Leeuwen, Piet W. N. M. (2009). "Bite angle effects of diphosphines in C–C and C–X bond forming cross coupling reactions". Chemical Society Reviews. 38 (4): 1099–118. doi:10.1039/B806211K. PMID 19421583.
2. 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 (8): 2741–2769. doi:10.1021/cr9902704. PMID 11749304.CS1 maint: multiple names: authors list (link)
3. 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" (PDF). Organometallics. 14 (6): 3081–3089. doi:10.1021/om00006a057.CS1 maint: multiple names: authors list (link)