title: Production and reactions of organic-soluble lanthanide complexes of the monolacunary Dawson [alpha1-P2W17O61]10- polyoxotungstate.
abstract: The incorporation of lanthanides into polyoxometalates provides entry to new classes of potentially useful materials that combine the intrinsic properties of both constituents. To utilize the [alpha1-Ln(H2O)4P2W17O61]7- species in applications of catalysis and development of luminescent materials, the chemistry of this family of lanthanide polyoxometalates in organic solvents has been developed. Organic-soluble polyoxometalate-lanthanide complexes TBA5H2[alpha1-Ln(H2O)4P2W17O61] (Ln = La(III), Sm(III), Eu(III), Yb(III)) were prepared and characterized by elemental analysis, acid-base titration, IR, 31P NMR, and mass spectrometry. The synthetic procedure involves a cation metathesis reaction in aqueous solution under strict pH control. A solid-liquid-phase transfer protocol yielded a unique species (TBA)8K3[Yb(alpha1-YbP2W17O61)2] with three ytterbium ions and two [alpha1-P2W17O61]10- polyoxotungstates. A centrosymmetric dimeric complex [{alpha1-La(H2O)4P2W17O61}2]14- was crystallized from aqueous solution and characterized by X-ray diffraction. ESI mass spectral analysis of the complexes TBA5H2[alpha1-Ln(H2O)4P2W17O61] shows that similar dimers exist in organic solution, in particular for the early lanthanides. Fragmentation in the mass spectrometer of the complexes from dry acetonitrile solution involves double protonation of an oxo ligand and loss of one water molecule. Low mass tungstate fragments combine into [(WO3)n]2- (n = 1-5) ions and their condensation products with phosphate. Reaction of TBA5H2[alpha1-Eu(H2O)4P2W17O61] with 1,10-phenanthroline or 2,2'-bipyridine showed an increase of the europium luminescence. This result is explained by the formation of a ternary complex of [alpha1-Eu(H2O)4P2W17O61]7- and two sensitizing ligands.
authors.affiliation: Laboratoire de Chimie Inorganique et Matériaux Moléculaires, UMR CNRS 7071, Institut de Chimie Moléculaire FR 2769, Université Pierre et Marie Curie, Case Courrier 42, 4 place Jussieu, 75005 Paris, France.
authors.forename: Cécile
authors.initials: C
authors.lastname: Boglio
authors.forename: Géraldine
authors.initials: G
authors.lastname: Lenoble
authors.forename: Carine
authors.initials: C
authors.lastname: Duhayon
authors.forename: Bernold
authors.initials: B
authors.lastname: Hasenknopf
authors.forename: René
authors.initials: R
authors.lastname: Thouvenot
authors.forename: Cheng
authors.initials: C
authors.lastname: Zhang
authors.forename: Robertha C
authors.initials: RC
authors.lastname: Howell
authors.forename: Benjamin P
authors.initials: BP
authors.lastname: Burton-Pye
authors.forename: Lynn C
authors.initials: LC
authors.lastname: Francesconi
authors.forename: Emmanuel
authors.initials: E
authors.lastname: Lacôte
authors.forename: Serge
authors.initials: S
authors.lastname: Thorimbert
authors.forename: Max
authors.initials: M
authors.lastname: Malacria
authors.forename: Carlos
authors.initials: C
authors.lastname: Afonso
authors.forename: Jean-Claude
authors.initials: JC
authors.lastname: Tabet
mesh_terms: D002412:Cations / Q000737:chemistry; D018360:Crystallography, X-Ray; D028581:Lanthanoid Series Elements / Q000737:chemistry*; D009682:Magnetic Resonance Spectroscopy / Q000379:methods; D009942:Organometallic Compounds / Q000138:chemical synthesis* / Q000737:chemistry; D010759:Phosphorus Isotopes; D012680:Sensitivity and Specificity; D012995:Solubility; D019032:Spectrometry, Mass, Matrix-Assisted Laser Desorption-Ionization / Q000379:methods; D013055:Spectrophotometry, Infrared; D013237:Stereoisomerism; D017973:Tungsten Compounds / Q000737:chemistry*
chemical_list: D002412:Cations; D028581:Lanthanoid Series Elements; D009942:Organometallic Compounds; D010759:Phosphorus Isotopes; D017973:Tungsten Compounds