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Darstellung, n B- und 19F-NMR-Spektren des Monofluoropentaiodo- c/östf-hexaboratanions sowie Kristallstruktur von (CH2Py2)[B6FI5] Synthesis, 1 ‘B and 19F NMR Spectra of the Monofluoropentaiodo-c/oso-hexaborate Anion and the Crystal Structure of (CH2Py2)[B6FI5] H. Thomsen, W. Preetz* Institut für Anorganische Chemie der Christian-Albrechts-Universität, Ohlshausenstraße 40, D-24098 Kiel Z. Naturforsch. 53 b, 829-832 (1998); eingegangen am 11. Mai 1998 Monofluoropentaiodo-c/<wo-hexaborate(2-), Crystal Structure, n B and 19F NMR Spectra By reaction of c/o5o-[B6H5F

1,5Pt- und 19F-NMR-Spektren der Fluoro-Chloro-Platinate(rV), IP «F A „P -, n = 0 -6 195Pt and 19F NMR Spectra of the Fluoro-Chloro-Platinates(IV), [ P t F „ C ^ , n = 0 - 6 E. Parzich, G. Peters und W. Preetz* Institut für Anorganische Chemie der Christian-Albrechts-Universität, Olshausenstraße 40, D-24098 Kiel Z. Naturforsch. 48b, 1169-1174 (1993); eingegangen am 14. Juni 1993 Fluoro-Chloro-Platinates(IV), 195Pt NM R Spectra, 19F N M R Spectra, Stereoisomers The 10 com plex ions of the system [PtF^Cl^J2-, n = 0 - 6 , including the three pairs of stereoisom

Darstellung von Antimon(V)tetrafluorid- pentafluorotellurat(YI), SbF4OTeF5 und Antimon(V)trifluorid-bis[pentafluoro- tellurat(VI)], SbF3(OTeF5)2 Preparation of Antimony(V)tetrafluoride- pentafluorotellurate(VI), SbF4OTeF5 and Antimony(V)trifluoride-bis[pentafluoro- tellurate(VI)], SbF3(OTeF5)2 Ortwin Leitzke und Fritz Sladky* Institut für Anorganische und Analytische Chemie der Universität Innsbruck, Innrain 52 a, A-6020 Innsbruck Z. Naturforsch. 86 b, 268-269 (1981); eingegangen am 13. Oktober 1980 Synthesis, 19F NMR Spectra, Pentafluorotell urates

By ligand exchange reactions of (n-Bu4N )[ReOBr4] with NaI dissolved in acetone pure (n-Bu4N )[ReOI4], and with AgSCF3 suspended in dichloromethane (n-Bu4N )[ReO(SCF3)4] have been prepared for the first time. The vibrational spectra of both complexes are assigned according to point group C4v, supported by normal coordinate analysis based on a general valence force field. 13C and ,19F NMR spectra provide evidence for the equivalence o f the SCF3 groups.

Abstract

Tetrafluorosilane and phenyltrifluorosilane react with the O-trimethylsilyl derivatives of N.N-disubstituted aminoethanols and with the N-trimethylsilyl derivative of N.N.N′-trimethylethylene diamine to give the corresponding monosubstituted fluorosilyl compounds in which, on the basis of 19F NMR spectroscopic studies, intramolecular N -Si bonding raises the coordination number of silicon from four to five (i.e. λ4Si -> λ5Si). The low temperature 19F NMR data suggest a trigonal-bipyramidal configuration at λ5 Si with an axial N -Si coordinate bond.

The first fluorine-containing cryptand F3-TREN 4 for the complexation of anions was prepared in the 3 + 2-condensation reaction of 2-fluoro-1,3-phthalaldehyde 3 with tris(2-aminoethyl) amine and subsequent reduction with NaBH4. Upon incorporation of anionic guests 4 ·6HClO4 experiences shifts of its 19F NMR resonances and thus demonstrates the advantages of studying host-guest association by 19F NMR spectroscopy.

Abstract

19F NMR chemical shifts of 14 fluorine substituted cis-Bis(phenyl)bis(triphenylphos-phane)platinum(II) compounds are discussed with respect to dπpπ-interactions between platinum and sp2 -hybridized carbon.

By stereoselective ligand exchange reactions of [PtF5Cl]2− and cis-[PtF4Cl2]2− with Brmixtures containing seven different fluoro-chloro-bromo- and two fluoro-bromo-platinates(IV) are formed, from which trans-Cs2[PtF4ClBr] 4t 11 and mer-Cs2[PtF3Clc 2Br] 3m2c 1 have been isolated by ion exchange chromatography on DEAE cellulose. All threefold mixed complexes could be detected by in situ 19F and 195 Pt NMR measurements. Due to the stronger trans influence of Cl in comparison with F on asymmetric F′-Pt-Cl′ axes the F atoms are deshielded and their signals δ(19F) are shifted on the average by 106 ppm to lower field as compared with δ(19F) of symmetric F-Pt-F axes. For the same reason the mean coupling constant 1J(FPt) of 1857 Hz is 44 % higher than 1J( FPt) of 1288 Hz. The substitution of a cis positioned Cl against Br causes shifts of -7,6 ppm for δ(19F) and of -8,4 ppm for δ(19F ). The cis influence on the coupling constants 1J(F P t) and 1J( FPt), on the average 4 Hz, is more than two orders of magnitude smaller than the trans influence. The coupling constants between inequivalent F atoms 2J(FF) amounts to 44 Hz. The mean highfield shift of the l95Pt signals on exchange of one F for Cl is 1177, of one Cl for Br 210 ppm. Due to the increasing trans influence F < Cl < Br on the stretching vibrations of asymmetrically coordinated axes characteristic frequency shifts of up to 15 % are observed. The normal coordinate analyses performed on 4t11 and 3m2c 1 reveal that the force constant fd(PtF) is by 15 % higher than fd(PtF), and that fd(PtCl′) is by 31 % higher than fd(PtCl). Very intense Raman bands at 277 and 267 cm −1 are explained by strong vibrational coupling of the π-deformation with a symmetric valence mode of the Cl -Pt-Br′axis.

Chemie der Phosphorfluoride, X X X V II1 19F-Kernm agnetische Resonanzuntersuchungen an Phosphorpentafluorid-Basen-Kom plexen Phosphorus-Fluorine Chemistry, X X X V II 19F Nuclear Magnetic Resonance Investigation of Phosphorus Pentafluoride-Base Complexes K l a u s - P e t e r J o h n und R e i n h a r d S c h m u t z l e r Lehrstuhl B für Anorganische Chemie der Technischen Universität Braunschweig (Z. Naturforsch. 29 b, 730-733 [1974]; eingegangen am 29. August 1974) 19F NMR, Phosphorus fluorides, AB4X spinsystem The 19F NMR spectra of some PF5-base

, CßFö, CÖHÖS, CßFöS were prepared, and all ten compounds investigated. Thermal stability, UV/VIS-, IR- and 19F-NMR-spectra depend strongly on the combination of the substituents. Einleitung Für eine vergleichende Untersuchung auf dem Gebiet der aromatisch substituierten Schwefeldi- imide, bei der die Einflüsse der Phenyl- und Penta- fluorphenylgruppe sowie der entsprechenden Sul- fenylgruppen auf das Schwefel-Stickstoff-System festgestellt werden sollten, wurde eine in sich ge- schlossene Gruppe von Verbindungen untersucht. Die symmetrische und asymmetrische