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