DFT calculations of 31P spin-spin coupling constants and chemical shift in dioxaphosphorinanes

2011 ◽  
Vol 49 (7) ◽  
pp. 399-404 ◽  
Author(s):  
Magdalena Pecul ◽  
Mateusz Urbańczyk ◽  
Artur Wodyński ◽  
Michał Jaszuński
Keyword(s):  
Chemical Shift ◽  
Dft Calculations ◽  
Coupling Constants ◽  
Spin Coupling ◽  
Spin Coupling Constants ◽  
Spin Spin Coupling

Hyperconjugation In Trialkylboranes Shown By Indirect Nuclear Spin-Spin Coupling Constants. Experimental Data And Density Functional Theory (Dft) Calculations

2005 ◽  
Vol 60 (3) ◽  
pp. 259-264 ◽  
Author(s):  
Bernd Wrackmeyer ◽  
Oleg L. Tok
Keyword(s):  
Experimental Data ◽  
Dft Calculations ◽  
Density Functional ◽  
Calculated Data ◽  
Coupling Constants ◽  
Spin Coupling ◽  
Functional Theory ◽  
Spin Coupling Constants ◽  
Spin Spin Coupling ◽  
C Nmr

Trimethylborane (1), triethylborane (2), 1,3-dimethyl-1-boracyclopentane (3), 1-methyl-1- boracyclohexane (4), 9-methyl- and 9-ethyl-9-borabicyclo[3.1.1]nonane [5(Me) and 5(Et)], and 1- boraadamantane (6) were studied by 11B and 13C NMR spectroscopy with respect to coupling constants 1J(13C,11B) and 1J(13C,13C). Results of DFT calculations at the B3LYP/6-311+g(d,p) level of theory show satisfactory agreement with the experimental data. Hyperconjugation arising from C-C σ bonds adjacent to the tricoordinate boron atom is indicated, in particular for 1-boraadamantane (6), by the optimised calculated structures, and by the experimental and calculated data 1J(13C,13C). The calculated magnitude of 1J(13C,1H) for carbon atoms adjacent to boron becomes significantly smaller if the optimised structures suggest hyperconjugative effects arising from these C-H bonds

69/71Ga and 115In NMR Spectroscopy of Lithium Tetra(tert-butyl)gallate and -indate: Spin-Spin Coupling Constants 1J(69/71Ga,13C) and 1J(115In,13C)

2009 ◽  
Vol 64 (1) ◽  
pp. 41-46
Author(s):  
Bernd Wrackmeyer ◽  
Elena V. Klimkina
Keyword(s):  
Nmr Spectroscopy ◽  
Dft Calculations ◽  
Nmr Spectra ◽  
Coupling Constants ◽  
Spin Coupling ◽  
Tert Butyl ◽  
Spin Coupling Constants ◽  
Spin Spin Coupling ◽  
First Time

The 13C, 69/71Ga and 115In NMR spectra of lithium tetra(tert-butyl)gallate and -indate were measured under various conditions. It proved possible to determine for the first time the coupling constants 1J(69/71Ga,13C) = 182 Hz/232 Hz and 1J(115In,13C) = 310±10 Hz for these metallates under conditions for solvent-separated ions. DFT calculations [B3LYP/6-311+G(d,p)] were carried out for organogallium compounds such as tri(tert-butyl)gallium, trimethylgallium and tetramethylgallate in order to predict and confirm coupling constants 1J(Ga,13C).

Analysis of the proton and fluorine magnetic resonance spectra of 1,3,5-trifluorobenzene dissolved in a nematic liquid crystal

1968 ◽  
Vol 46 (17) ◽  
pp. 2783-2786 ◽  
Author(s):  
C. T. Yim ◽  
D. F. R. Gilson
Keyword(s):  
Liquid Crystal ◽  
Magnetic Resonance ◽  
Chemical Shift ◽  
Nematic Liquid Crystal ◽  
Coupling Constants ◽  
Spin Coupling ◽  
Spin Coupling Constants ◽  
The Absolute ◽  
Spin Spin Coupling ◽  
Magnetic Resonance Spectra

The proton and fluorine magnetic resonance spectra of 1,3,5-trifluorobenzene oriented in a nematic liquid crystal have been analyzed. The proton and fluorine chemical shift anisotropies are −2.98 p.p.m. and 104 p.p.m. respectively. The absolute signs of the indirect spin–spin coupling constants are: JHH′, JFF, and JHF (ortho) all positive, and [Formula: see text] (para) negative.

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