title: Using Functionalized Silyl Ligands To Suppress Solvent Coordination to Silyl Lanthanide(II) Complexes.
abstract: The reaction of the potassium 1,3-trisilanediide Me2Si[Si(Me3Si)2K]2with SmI2and YbI2was found to give the respective disilylated complexes Me2Si[Si(Me3Si)2]2Sm·2THF and Me2Si[Si(Me3Si)2]2Yb·2THF. Desolvation of coordinated solvent molecules in these complexes made their handling difficult. However, using a number of functionalized silanide ligands, complexes with a diminished number or even no coordinated solvent molecules were obtained ((R3Si)2Ln(THF)x(x = 0-3)). The structures of all new lanthanide compounds were determined by X-ray single-crystal structure analysis. NMR spectroscopic analysis of some Yb-silyl complexes pointed at highly ionic interactions between the silyl ligands and the lanthanides. This bonding picture was supported by DFT calculations at the B3PW91/Basis1 level of theory. Detailed theoretical analysis of a disilylated Eu(II) complex suggests that its singly occupied molecular orbitals (SOMOs) are very close in energy to the ligand silicon lone pairs (HOMO), and SQUID magnetometry measurements of the complex showed a deviation from the expected behavior for a free Eu(II) ion, which might be due to a ligand-metal interaction.
authors.affiliation: Institut für Anorganische Chemie, Technische Universität Graz , Stremayrgasse 9, 8010 Graz, Austria.
authors.forename: Rainer
authors.initials: R
authors.lastname: Zitz
authors.affiliation: Institut für Anorganische Chemie, Technische Universität Graz , Stremayrgasse 9, 8010 Graz, Austria.
authors.forename: Johann
authors.initials: J
authors.lastname: Hlina
authors.affiliation: Institut für Anorganische Chemie, Technische Universität Graz , Stremayrgasse 9, 8010 Graz, Austria.
authors.forename: Mohammad
authors.initials: M
authors.lastname: Aghazadeh Meshgi
authors.affiliation: Institut für Physik, Fachbereich Experimentalphysik, Magnetometry und Photonics, Universität Graz , Universitätsplatz 5, 8010 Graz, Austria.
authors.forename: Heinz
authors.initials: H
authors.lastname: Krenn
authors.affiliation: Institut für Anorganische Chemie, Technische Universität Graz , Stremayrgasse 9, 8010 Graz, Austria.
authors.forename: Christoph
authors.identifier: http://orcid.org/0000-0001-8586-2889
authors.initials: C
authors.lastname: Marschner
authors.affiliation: Department of Chemical & Biological Engineering, University of Wisconsin-Madison , 1415 Engineering Drive, 53706 Madison, Wisconsin, United States.
authors.forename: Tibor
authors.initials: T
authors.lastname: Szilvási
authors.affiliation: Institut für Chemie, Universität Graz , Stremayrgasse 9, 8010 Graz, Austria.
authors.forename: Judith
authors.identifier: http://orcid.org/0000-0002-9938-1813
authors.initials: J
authors.lastname: Baumgartner