title: Polynuclear platinum phosphanido/phosphinito complexes: formation of P-O and P-O-P bonds through reductive coupling processes.
abstract: A mixture of the asymmetric complexes of formula [(RF)2Pt(μ-Ph2PO)(μ-PPh2)Pt(μ-PPh2)2Pt(solv)(solv')] [(1-(solv)(solv')] (solv, solv' = acetone, H2O, CH3CN) has been prepared by reaction of [(RF)2Pt(II)(μ-PPh2)2Pt(II)(μ-PPh2)2Pt(II)(NCCH3)2] with AgClO4 in CH3CN/acetone. The lability of the Pt-solvent bonds allows the displacement of the coordinated solvent molecules by dppm or Cl(-) and the isolation of the tri- or hexanuclear phosphanido/phosphinito Pt(ii) complexes [(C6F5)2Pt(μ-PPh2)(μ-PPh2O)Pt(μ-PPh2)2Pt(dppm)] (2) or [NBu4]2[(C6F5)2Pt(μ-PPh2)(μ-PPh2O)Pt(μ-PPh2)2Pt(μ-Cl)2Pt(μ-PPh2)2Pt(μ-PPh2)(μ-PPh2O)Pt(C6F5)2] (as a mixture of the two possible isomers 4a and 4b). Complex 2 reacts with AgClO4 to form the tetranuclear derivative [(C6F5)2Pt(μ-PPh2)(μ-PPh2O)Pt(μ-PPh2)2Pt(dppm)Ag(OClO3)] (3), which displays two Pt-Ag donor-acceptor bonds. The mixture of the hexanuclear isomers 4a-4b reacts with Tl(acac) producing the acetylacetonato complex [NBu4][(C6F5)2Pt(μ-PPh2)(μ-PPh2O)Pt(μ-PPh2)2Pt(acac)] (5) which, upon reaction with HCl, yields back the mixture of 4a-4b. The reaction of 4a-4b with PPh3 produces [NBu4][(C6F5)2Pt(μ-PPh2)(μ-PPh2O)Pt(μ-PPh2)2Pt(Cl)(PPh3)] (6) as a mixture of isomers with the chloro ligand located syn (6a) or anti (6b) to the PPh2O(-) group. Either the reaction of 6 with AgClO4 or the treatment of 5 with HPPh3ClO4 results in the formation of the species [(C6F5)2Pt(II)(μ-PPh2)2Pt(I)(μ-PPh2OPPh2)Pt(I)(PPh3)] (7) (44 VEC), which can be explained as the consequence of a PPh2O/PPh2 reductive coupling and a rearrangement of ligands in the molecule generating a Pt(ii),Pt(i),Pt(i) compound. All complexes were characterised in the solid state by XRD (only one of the isomers, in the cases of 4 and 6) and in solution by NMR spectroscopy.
authors.affiliation: Departamento de Química Inorgánica, Instituto de Síntesis Química y Catálisis Homogénea, Universidad de Zaragoza - CSIC, 50009 Zaragoza, Spain. juan.fornies@unizar.es.
authors.forename: Irene
authors.initials: I
authors.lastname: Ara
authors.forename: Juan
authors.initials: J
authors.lastname: Forniés
authors.forename: Susana
authors.initials: S
authors.lastname: Ibáñez
authors.forename: Piero
authors.initials: P
authors.lastname: Mastrorilli
authors.forename: Stefano
authors.initials: S
authors.lastname: Todisco
authors.forename: Vito
authors.initials: V
authors.lastname: Gallo