1211548-92-3Relevant academic research and scientific papers
Bisphosphine monoxides with o-phenylene backbones in Pt, Pd and Fe complexes
Farrer, Nicola J.,McDonald, Robert,Piga, Toria,McIndoe, J. Scott
, p. 254 - 261 (2010/04/04)
A new route to aromatic bisphosphine monoxides has been explored through ortholithiation of triphenylphosphine oxide and subsequent reaction of the lithiated intermediate with a range of alkyl and aryl phosphine chlorides. Routes to the known bisphosphine monoxide (BMPO) (o-C6H4){P(O)Ph2}PPh2 (2aO) and a range of new BPMOs of the type Ph2P(O)(o-C6H4)PR2 where R2 = iPr2, Cy2, Et2 are described. Reaction of 2aO with MCl2(cod) (M = Pd, Pt; cod = cyclooctadiene) gives products of the form [MCl(κ1-P-2aO)(κ2-P,O-2aO)]+ Cl- and MCl2(κ2-P,O-2aO); the former exhibits fluxional behaviour which has been analysed by 195Pt NMR and 31P variable-temperature NMR spectroscopy. The bidentate complex is not fluxional for either the Pd or the Pt example; the Pt complex PtCl2(κ2-P,O-2aO) has been characterised by X-ray crystallography. By comparison of the product distribution seen by 31P NMR spectroscopy and ESI-MS it was established that the different coordination modes of 2aO result in quite different behaviour of the complexes when studied by ESI-MS; when the O is formally coordinated to the metal its ionisation efficiency is very low. Synthesis of Fe(CO)4(2aO) confirmed the ability of the 2aO ligand to render a neutral complex with no alternative pathways for ionisation to be readily detected by ESI-MS.
