Geminal2J(29Si‐O‐29Si) couplings in oligosiloxanes and their relation to direct1J(29Si‐13C) couplings
Authors:
- 14 July 2011
- journal article
- research article
- Published by Wiley in Magnetic Resonance in Chemistry
- Vol. 49 (8) , 492-501
Abstract
Absolute values of (79) geminal2J(29Si‐O‐29Si) couplings were measured in an extensive series of (55) unstrained siloxanes dissolved in chloroform‐d. Signs of2J(29Si‐O‐29Si) in some (9) silicon hydrides were determined relative to1J(29Si‐1H) which are known to be negative. It is supposed that positive sign of the2J(29Si‐O‐29Si) coupling found in all studied hydrides is common to all siloxanes. Theoretical calculations for simple model compounds failed to reproduce this sign and so their predictions of bond length and angle dependences cannot be taken as reliable. Useful empirical correlations were found between the2J(29Si‐O‐29Si) couplings on one side and the total numbermof oxygen atoms bonded to the silicon atoms, sum of29Si chemical shifts or product of1J(29Si‐13C) couplings on the other side. The significance of these correlations is briefly discussed. Copyright © 2011 John Wiley & Sons, Ltd.Keywords
Funding Information
- Grant Agency of the Academy of Sciences of the Czech Republic (IAA 400720706)
- Czech Science Foundation (203/08/P412)
This publication has 69 references indexed in Scilit:
- Multiple receiver experiments for NMR spectroscopy of organosilicon compoundsApplied Organometallic Chemistry, 2010
- 2J(29Si-O-29Si) coupling constants in oligosiloxanesMagnetic Resonance in Chemistry, 2007
- Monosodiumoxyorganoalkoxysilanes: Synthesis and propertiesHeteroatom Chemistry, 2006
- Comparison of Carbon−Silicon Hyperconjugation at the 2- and 4-Positions of the N-Methylpyridinium CationThe Journal of Organic Chemistry, 2005
- 29Si NMR Spektroskopie von CyclopentasilanenSpectrochimica Acta Part A: Molecular Spectroscopy, 1993
- SiSi-Kopplungskonstanten symmetrischer disilaneSpectrochimica Acta Part A: Molecular Spectroscopy, 1991
- 29Si-29Si Long Range Couplings in Strained Cyclic PolysilanesAngewandte Chemie International Edition, 1988
- Proton-13C Spin-Spin Coupling. V. Inadequacy of Correlation of Proton-13C Coupling with s-CharacterJournal of the American Chemical Society, 1964
- Correlation of JC13–H with τ and the Significance of this RelationshipThe Journal of Chemical Physics, 1963
- C13 Splittings in Proton Magnetic Resonance Spectra. I. HydrocarbonsThe Journal of Chemical Physics, 1959